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1978 - American Radio History

1. 215 350 Programs Punched tape with documentation 11 available oach o oss teneatis epe vee aa 15 MEMORIES High speed 4 MHz RAM cards for use with high speed 2 80 computers Switch selected bank ad dressing allows organization into 512k memory eight banks of 64k each banks selected under software control also allows time sharing with mini mum Software overhead Addresses switch select able A4KZ 4k static Kit wired 195 295 16K2 16k Kit wired sess 495 795 Bytesaver 8k PROM memory with built in program mer for 2708 PROMS Kit wired 145 245 16k PROM Card Holds up to sixteen 2708 PROMs Has bank select feature for large memory systems see Memories above and address select Ad dress anticipation feature eliminates wait states on sequential addresses at 4 MHz 16KPR Kit wired ooo eee 145 245 D 7A ANALOG INTERFACE VO board with seven channels of eight bit analog to digital conversion for input seven channels D A for output plus one eight bit parallel digital I O port For process control digital filtering games oscillo Scope graphics speech and music uses Analog signal range 2 56 to 2 54 V Takes 0 4 A 8 V 30 mA 18 V 60 mA 18 V Kit wired n TM UNE 145 245 TRT TU ART DIGITAL INTERFACE Digital O board with two serial two eight bit paral lel 1 O ports plus 10 independent p
2. 6 3 8 I40 HOLE a 250 HOLE Fig 2 Instructions aud dimensions for making the heat sink Et must hare at least 900 sq in of cooling surface discrete transistor class B pair C1B Q7 and Q2 and T1 Transistors Q3 and Q4 are medium power amplifiers each one Darlington connected to three high power transistors Q8 Q9 Q10 and Q5 06 Q7 Transformer 72 is theload for the high power transistors and provides the 117 volt output at the preset sine wave frequency Load regulation is provided by feedback from the emitter of Q7 to potentiometer R11 and then to the os cillator Reguation from no load to full load is better than 695 When switch S7 is set to CHARGE the circuit except for Q5 through Q10 is disconnected from the battery and the six high power transistors act as rectifiers The secondary of 72 is con nected so that the proper charging current is obtained An 18 ampere circuit breaker is mounted on the output stage heat sink 1978 Edition to monitor the temperature and cur rent drain If the heat sink gets too hot due to improper ventilation the cur rent rating of the circuit breaker re duces proportionately Thus the in verter is protected from improper mounting or application The zero center ammeter M1 indi cates the current drain when the cir cuit is inverting and the charging cur rent when it is recharging a battery Construction The crucial elemen
3. rrt 350 450 680b BSM 16k static memory card for 680b up to three may be used internal power supply will sup port two without additions Kit wired 685 865 680b UIO Universal I O for 680b with one parallel I O serial RS 232 20 mA ports Kit wired e we Lb sMu ave athe eae acca 110 160 680b UIO 2P Same less serial 60 75 680b UIO S Same serial port only 65 100 KCACR Audio cassette interface Kansas City standard Wired oc eecsec eset ee to tuve enata Eni iiee 250 680 PCI Process control interface with eight relay outputs for external device control eight optically isolated inputs for sensory and control information PW OC Or ae ene ene 165 275 MORROW S MICRO STUFF 8080 MICROPROCESSOR BOARD Combination 8080 MPU front panel board with oc tal keypad and display two on board F O ports for keyboard 256 byte RAM and 256 byte ROM Fa cilities to start stop or step any program processor remains active after HALT command Kit 250 MOS TECHNOLOGY KIM 1 MICROCOMPUTER 6502 MPU single board computer with 1 1 k RAM 2k ROM monitor 20 mA serial interface 23 key control and hex data entry keypad terminals pro vided for additional remote keypad six digit LED in confined areas with new compact Electronic Technician rili AC or 12V powered it s only 5 long plus B bit Holds 3756 aid 71 bits included or ot
4. RESET CIRCUIT IC7 IC8 IC9 OIGITAL VERTICAL SCAN COUNTER IC3 ICA IC6 QI Z AXIS oa conv AMP VERT awP Q2 03 Q4 INTENSITY V INPUT ee OSCILLOSCOPE HORIZONTAL SCAN COUNTER Fig 1 Logie diagram of the camera shows how scan counters address camera and also generate sweep ve signals for the scope IC5 IC D A CONV BORIZ AMP H INPUT 87 PARTS LIST C1 C2 420 00i 4 F disc capacitor C3 C4 C5 20 1 4F disc capacitor C6 330 pF disc capacitor C7 C8 C9 20 014F disc capacitor Di to D4 1N914 diode D5 N5242 12 volt zener diode 1C1 1024 element image sensor 1C2 1C9 7402 TTL quadruple 2 input NOR gate 1C3 IC5 1C6 1C7 7493 TTL 4 bit bi nary counter 1C4 7404 TTL hex inverter 1C8 7400 TTL quadruple 2 input NAND gate 1C10 MC7805CP S volt regulator 11 12 547 pilot light J1 to J4 Banana jacks QI Q2 Q3 2N30640 transistor Q4 Q5 2N3904 transistor Ri 100 ohm 2 watt miniature poten tiometer R2 100 ohm 2 watt resistor R3 560 ohm 4 watt resistor R4 to RI8 and R52 1000 ohm watt resistor R19 15 000 ohm watt resistor R20 to R31 20 000 ohm 14 watt 8 resis R32 to R39 10 000 ohm watt S resis R40 to R44 100 ohm watt resistor R45 R46 68 000 ohm 14 watt resistor R47 R48 5600 ohm watt resistor R49 1800 ohm V watt resistor R50 18 000 ohm 4 watt resistor R5
5. sssese ene 35 MICROCOMPUTER ASSOCIATES JOLT 6502 MPU low cost system with DEMON debug monitor in ROM interfaces automatically to any ter minal speed from 10 to 30 char sec Includes serial interface with 20 mA or RS 232 512 byte RAM memory 16 programmable I O lines power on re set Requires 42 V 5 V 10 V Expandable with modules below Kit wired 259 245 SUPER JOLT Similar to JOLT but with 1k RAM 32 programmable 1 O lines interval timer four interrupts three serial interfaces 20 mA RS 232 and TTL 5k ROM monitor resident assembler and Tiny BASIC inter preter Wired with without assembler and BASIC ROMS A ete ees ae 375 575 OEM SYSTEM CARDS JOLT compatible MPU cards with choice of BO80A 6502 6800 or 2650 processor Includes clock 1k RAM sockets for 2k PROM or 4k ROM 24 bidirec tional I O lines fully buffered address data lines in terrupts Supported by JOLT modules below serial I O 8080A 9080A Assembled 375 JOLT 2k PROM Wired sse 149 JOLT 4k RAM Kit wired sss 199 285 JOLT i O Peripheral interface parallel adapter two PIA chips 32 O lines four interrupt lines fully pro grammable Kit wired 96 140 JOLT 6502 Resident Assembler In ROM requires 2k PROM card at least 4k RAM Delivered on 7 PROMSTITOPA uices R ELE 395 JOLT Universal Card Blank drilled for 14 16 2
6. B the same height above the pc board be fore soldering the leads in place Also be certain that the RUN LOAD and MEMORY PROTECT P switches can be locked down on or up off before soldering There are 10 solder pads along the properly orienting them and inserting their plastic alignment pins in the appro priate holes at each switch position The correct key placement is shown in the photograph Make sure that the tops of all keys including the control keys are DATA BUS D4 D5 D6 D7 D D D2 D3 5 O 14 HI 9 ae iv VVYVEHVVYYVY Pon 15 i2 4 2 4 2 3 7 2 6 2 6 AB B Al2 8 9308 ws d 9308 a 4 IO R4 RI7 I2 0 4 3 g e d C b a f g e d C b a f 16 NSN 373 DIS 1 Fig 3 A pair of 7 segment LED readouts working with a pair of decoder lateh driver IC s form the low cost hex display ELECTRONIC EXPERIMENTER S HANDBOOK A9 T4CIT3 9 C4 ASpF Fig 4 Standard hex keypad works in conjunction with a keyboard decoder chip having a 2 key rollover KEY PAD 5V EE TOEN A mating clip on connector strip is mounted to the pc board directly above the 10 pads and tabs on the connector strip are soldered to the associated board pads The other side of this termi nal strip the side away from the pc board is fitted with screw connectors for making external connections After installing this strip mount A18 the 5 volt regulator on a 1 x 34 x 14 thick alumi num strip positioned
7. 32 L voice If it isn t just write __ Canada or Mexico 17 50 C Europe Air Delivered 25 CANCEL across the in voice and mail it back You won t be billed and the C Surface delivery to all other countries except Europe Canada or Mexico 25 Air j delivery available on request C Check enclosed Bonus one extra issue first issue is yours Please remit in U S funds C Bill me T Bill BankAmericard Bill Master Charge J Allow 6 to 8 weeks for Processing Card number Expiration date E Signature Name please print 1 Byte Publications inc 1977 Address i City E State Country Code CIRCLE NO 3 ON FREE INFORMATION CARD 118 ELECTRONIC EXPERIMENTER S HANDBOCK DIRECTORY OF MICROCOMPUTER PRODUCTS If you have any additional questions about products described in this Guide write direct to the company ADVANCED MICROCOMPUTER PRODUCTS P O Box 17329 Irvine CA 92713 AI CYBERNETIC SYSTEMS P O Box 4691 University Park NM 88003 APPLE COMPUTER 20863 Stevens Creek Blvd Cupertino CA 95014 AXIOM 5932 San Fernando Rd Glendale CA 91202 BYTE INC 1261 Birchwood Or Sunnyvale CA 94086 CANADA P O Box 516 La Canada CA 91011 CENTER FOR THE STUDY OF THE FUTURE 4110 N E Alameda Portland OR 97212 CENTRAL DATA P O Box 1484 Station A Champaign IL 61820 CORS MICROTECH INC P O Box 368 Southampton PA 18966 CHILD ODYSSEY ENTERPRISES P O Box 137 Alamogordo NM 88310 COMMODOR
8. CLOCK CHIPS BCD Outputs Reset PIN BCD Outputs 12 or 24 Hout BCD Outputs 1 PPS Output 32 0r 24 Hour 50 or 60 Hz Alarm 1 PPS Ovtpul videa Clock Chip For Use With MM5841 6 Digit Calendar Alarm 12 0r 24 Hur 25 22 45 38 37 1 09 95 115 400 4 50 4 50 1 15 35 2 00 100 79 Bg 245 90 1 50 25 275 78 79 295 2 95 9 95 325 Ch Cn 0o Ch OB amp Ll vabERSEidESEEREEBEBJ5SBSSSIJ m kin n iun mE cs d ur mun o HE Ln Cnm oo ao uo ua cn on ASSESS SSISRFSS 1 65 175 TTL 69 iH 1075 19 15 125 125 1 83 pum y 7 400N TL Uu mm SN74154N SN74155N SN74156N SN74157N SN74180N SN74151N SN74163N SN74154N SN74165N SN74166N SN74167N SN74170N SN741727N SN74173N 5N74174N SN74175N 5N74176N SNT7A177N SN741B0N SN74181N SN74182N SN74184N SN74185N SN741856N SN74187N SN74188N SN74190N SN74191N SN74192N 5N74193N SN74194N SN74195N SN74 1964 SN74197N SN74198N SN74199N SN74200N SN74279N SN74251N SN742B4N SN74285N SN74367N 20 Discount for 100 Combined 7400 s CMOS 74CO0N 74CO2N T4CO4N 74C10N 74020N 74C40N 74042N TACTAN TACTA 74C90N T4C85N TACIYO N 74C 151 746154 TAC157 ACtB0 74C161 740163 74C 164 740173 740193 740195 MC4044 MC14016 MSSBRSRBBBS 2 ca 195 2 20 15 00 6 00 395 118 125 LM1458C 65 LM1496N 95 LM1556V 1 85 LM1812N 6 95 LM2111N 1 95 LM2961N 2 95 LM3053 150 LM3U65N 89 LM3900N 55
9. TI IT VAC V TO DP AMPS V D 04 IN4003 Ql RI HEP 703 Th ci Q3 HEP80 S3 STOP C1 1000 uF 50 volt electrolytic capacitor C2 C3 100 uF 50 volt electrolytic capac itor D1 D8 1N4003 or similar silicon diode F1 0 5 ampere fuse 11 13 6 volt pilot lamp optionally in S1 S3 IC1 1C2 741 operational amplifier inte grated circuit or use dual version Ji J2 Banana jack one black one red QI HEP 703 power transistor Motorola Q4 HEPBOI PARTS LIST 2 2N4400 transistor or use Motorola HEP 736 Q3 Q4 HEP 801 FET Motorola R1 0 7 ohm resistor four 3 3 ohm 2 watt resistors in parallel R2 10 000 ohm potentiometer R3 R4 4700 ohm 2 watt resistor S1 S3 Normally open pushbutton switch Use Switchcraft No LUS 05 01 if built in 6 volt lamp ts desired 2 z u m o i t JI Controller cireuit is variation of a power supply regulator Potential on C3 determines track voltage level S4 Spst slide or toggle switch S5 Dhpdt center off switch T1 26 8 volt l ampere transformer Misc Heat sink for QI suitable enclosure fuse holder socket s for C and C2 perforated board and solder clips line cord strain relief or rubber grommet for line cord exit hole dry transfer lettering kit machine hardware hookup wire sol der etc Depressing increase speed switch S1 causes the output voltage at
10. im 1 r ecc Eger ee NR Other options include 8k and 300 nsec low power 8k memory boards 18 A power supply 4k EPROM board additional I O digital cassette storage drives and cabinet keyboard and printer see Peripherals section prototyping and extender cards 64 x 64 color graphics board E amp L MMD 1 MINI MICRO COMPUTER 8080A MPU educational microcomputer system with built in breadboard sockets comes with Bug book self teaching training course Features octal keyboard and binary display power supply 256 byte PROM operating system expandable on board to 512 bytes 512 byte RAM expansion available Kit assembled 423 600 MMD 1 MI Memory interface board with TTY and 300 baud cassette interfaces 1k RAM expandable on board to 2k 1k ROM Powered by MMD 1 Kit ge et TON 195 250 Also available are outboard octal and hex displays ports single step adapter programmable timer counter PROM 1702 programmer others MICRO DESIGNER Developmental modular microcomputer system openface configuration allows direct solderless ac cess to all bus lines control signals and power CPIC 80B CPU interface controller with 8080A clock buffers and control logic 175 MCP 80 B Control panel with switches and indicator lg Ma 184 MB 80 B Memory with 256 byte PROM plus RAM With 1k 2k 3k is esce teer tenes 180 220 260 ASB 80 B Serial interface
11. POPULAR ELECTRONICS 19 0 HANDBOOK sss INCLUDING HOBBYIST MICROCOMPUTER SECTION A Digital Logic Probe d d E Auto Ignition Timing E Light Photo wie 3 2 BAS Controller Single IC ge qe Weather Receiver ct ANGE Minivolts Meter D Y Night Cycling B Safety Lights ET HO Train Speed Control Low Cost TS 4 98 Metal Detector AL ROS Solid State TV QNS Camera Audio Compander ano more Complete Home y Computer Buying m Directory Ads A includes video graphics chip Uu 752 SWTPC announces first du minifloppy kit under 1 000 Be ont e Su cT Ga cm a i co w a m la ee f e F E ih EI i wt eS a a ot Le Comeuragr nu MINIELODDY aaa OISK SYSTEM SYSTEM Now SWTPC offers complete best buy computer system with 995 dual minifloppy 500 video terminal monito 395 4K computer gu 6800 Steven MINIFLORPPPY ur DISK SYSTEM 395 4K 6800 Computer The SWTPC 6800 comes complete with 4K memory serial interface power supply chassis famous Motoro MIKBUG mini operating system ir read only memory ROM and the most complete documentation with any computer kit Our growing software library includes 4K and 8K BASIC cassettes 4 95 and 9 95 paper tape 10 00 and 20 00 Extra 995 MF 68 Dual Minifloppy You need dual driv3s to get full te efits from a minifloppy So we waited o offer a f
12. RE S er Baler sau Ud PA atl Photograph of interior of the Tug Of War shows mounting of printed circuit board with power supply transformer and optional speaker for sound at right o D9 X Di0 9 p T ICIO A Q INSERT WIRE LEDI AND SOLDER BOTH ENDS e RI 5 JEND ia Ci e x C2 e e R7T e iE j w LED TRE UM ANODES v d C M Misenpo RPn PC LOWER LEDI PAD hoo 9 R23 e BOARD B UP EE CATH 9 R 1 9 PLN e R30 46 1 X c28 4 ee X Cio e eu E 7 2 fne x j E y 2 lo ae 1 R l e x SWITCHES LED 6 6e RI6 e CATH 6 ee RI5 e a HS ode Ri4 z9 Die x55 KR I 3 94 RI3 9 c27 e tang e R C24 e 37 6 2 ee RI2 9 e R36 e CI9 e X c2i e e c20 E 3 k x oi Be we Pa o R38 A R35 IC8 i hb 3 SOLDER TO amp me a ou 4m os GROUND PLANE B o PRO FOIL X C30 PX PECITE iK C239 e C22 pies oar Pa eR39 0 SPKR Q e Fig 7 Components must be mounted carefully since the top of the pe board is primarily a ground plane Some connections however are made to the top side of board asterisk Construction A double sided pc board such as that shown in Fig 6 can be used for the Tug of War Don t use sockets for the IC s Since the top of the pc board is primarily a ground plane itis important to remember
13. divider type of selection as in con ventional VTVM s would be preferred because of the better input resistance on low ranges However the voltage divider would have a value of shunt ing resistance across the input of the voltage follower which would require a rezeroing of the meter each time the range is switched With the conven tional 10 megohm resistance the bias voltage generated across the input would be 10 X 106 times 500 nA or 5 volts for the 500 microvolt range Thus the conventional resistor ap proach was used instead of a voltage divider Construction Most of the compo nents can be wired point to point A small board is required to mount the sockets for the IC s Two 8 pin mini DIP s can be accommodated in one 16 pin socket The potentiometers except for R17 can be fastened with epoxy ce ment at convenient locations within the cabinet Once they are adjusted it IS not necessary to have access to them Install R77 on the rear apron for easy access Connect the range selector resistors to the appropriate terminals on S1 As noted in the Parts List the high value resistors can be made up of smaller units The 9 volt power supplies are made up of conventional AA cells in plastic holders Calibration Before applying pow er to the Minivolter connect a 10 000 ohm potentiometer across the meter and set the potentiometer to its minimum value Adjust R13 and R14 to the far ends of their adjustments Then
14. ed states only as long as operating d c power is applied to the chip When this d c is removed the flip flops can as sume amp random state and lose data Some RAM memory boards include a battery backup to maintain data in the event of a momentary power failure ROM The other type of memory chip is called a ROM for Read Only Memory In a way a ROM can be thought of as a RAM whose flip flops are made to as sume a particular state when fixed so that they cannot change states even 83 when the operating d c power is re moved Since programs are called soft ware and the electronic components hardware software programs in a ROM are called firmware ROMs are used to hold programs or data that the computer will need nearly every time it s used Usually these pro grams include monitors or operating systems that tell the computer how to communicate with terminals or other peripherals sometimes they contain just bootstrap programs which tell the computer how to load in a monitor pro gram from tape or on the more com plex side a complete high level lan guage such as BASIC more on that shortly often ROMs hold the special bit patterns that create the alphanumeric characters printed on a CRT or printing terminal There are several types of ROM One is burned at the factory for a dedicated purpose such as a character generator Once created such a ROM cannot be used for any other purpose
15. or 3 2 mm phone jack in the playing field box next to the batteries and under the main pc board Connect it to the sound option pads on the main board A sepa rate 9 volt battery is used to power the option Suitable printed circuit etching and drilling and parts placement guides are shown in Fig 6 A 2 5 1 cm speak er is used It can be taped or epoxied to the 3144 x 2 x 1 8 3 x 54 x 2 9 cm case top plate after it has been drilled and lettered A miniature phone plug can be mounted directly in the bot tom side of the case to mate with the playing field jack Use Although it may appear to be easy to get a hit advancing the League set ting increases the difficulty Only the ba sic rules for a hit strike foul out etc must be understood before play can be gin You will soon notice how analogous Batter Up is to actual baseball in terms of pitcher strategy batters hand eye coordination and overall competitive spirit generated during play As with any other battery operated de vice the game should be turned off when not in use to preserve battery life When the LED s become dim and pitch ing cannot be initiated with the pitch Switch it is time to change the batteries 11 EVERY PROJECT ANOTHER REASON Design and test circuits as fast as you can think with CSC Proto Board Solderless Breadboards As quick as pushing in or pulling out components you can design test and modify all kinds of ci
16. rapa uro Sr Wee oro po wi COE macung ui dw ups age 1 A power supply binary switch input LED output and 156 byte memory Kit esseere 90 Wire wrapped version ssssseseee e 100 Additional memory 256 byte 0 000000 5 COMMODORE PET COMPUTER 2001 6502 MPU self contained computer Includes built in keyboard with 64 character ASCII uppercase plus 64 graphics related characters 9 in video dis play for graphics 40 character x 25 line alphanu merics or both 4k RAM memory 8k optional ex DERE IA V IA AA M E pandable to 32k 12k ROM including 8k BASIC in terpreter and 4k operating system built in audio cassette recorder file management system in BA SIC interfaces for additional recorder and IEEE 488 instrument interface bus Wired BEBE LM EM 595 795 COMP SULTANTS MICRO 440 4040 MPU 4 bit computer with hardware monitor continuous display of accumulator and carry bidi rectional address stepping single step With 256 bytes RAM and power supply less box mounting hardware and I O connectors Kit wired e tor E TE M Reena er te 174 194 Enclosure mounting hardware and I O connectors jun uuu T 40 Micro 440 with enclosure hardware and connec Ors rire RT 239 2k RAM Expansion Kit wired 154 184 2k PROM Board Kit wired 76 84 COMPUCOLOR 8001 8080 MPU terminal computer with 19 in color video display key
17. sembly probe end first into the body and push it home orienting the LED lenses under their respective holes Gently pullon the coaxial cable to take up the slack Then screw on the switch cap Testing The Probe Observing po larity connect the alligator clips to a PARTS LIST C 22 LnF 10 volt tantalum capacitor DI D2 IN914 diode IC 1 7404 integrated circuit IC 2 9601 integrated circuit I EDI LED3 Light emitting Monsanto MV 5022 Q1 2N 4401 transistor RI 1000 ohm watt resistor R2 390 ohm A watt resistor R3 6 8 ohm watt resistor R4 30 000 ohm watt resistor RS R7 330 ohm a watt resistor S Part of penlight flashlight Misc Printed circuit board probe tip penlight flashlight body insulating spaghetti 4 long X V2 diameter heat shrinkable tubing small diameter heat shrinkable tubing 3 length small diameter coaxial cable one black booted miniature alligator clip one red booted miniature alligator clip stranded and solid hookup wire solder etc diode variable dc source With S7 set to the stretch mode slowly advance from O to 5 volts At 2 8 volts the memory P LED should flash on then off as the potential is increased through 4 1 volts This condition can be used to check for low voltages With the supply set to 5 volts touch the probe tip to the common lead The LO LED should light while the P LED comes on for 200 ms When the com
18. 20 mA or RS 232 with paper tape reader control for ASR 33 207 IF 102 Motherboard with five slots 115 iF 101 Same with breadboard sockets 200 CDP 5 Power Supply 5 75 A with crowbar protection Onr 5 WINS cce ecce E M 285 ECD MICROMIND 6512A MPU computer with 8k memory expandable to 16k on board to 64k with expansions and to 64M d YR ue com lar un i with optional memory mapping Includes power supply cabinet 80 key keyboard with user defina ble characters graphics and alphanumeric video output audio cassette interface for up to four re corders ROM monitor Eight serial and one parallel VO pons Wired cept coe ee eee eee 988 MICROMIND II Same with 16k main memory memory mapping option for up to 64M memory analog I O vectored interrupt cycle suppression and message inter rupts all also available as options for MicroMind I Wege onec eu E eee 1387 32k Memory Expansion Board 1000 ELECTRONIC CONTROL TECHNOLOGY ECT 100 8080 8080 MPU computer in 20 slot card cage that fits 19 in racks with motherboard and power supply 8080 MPU card with power on jump to selectable starting address for systems with ROM monitors 20 card connectors and guides Kit wired pU RM RECEN TEM UE EE 320 500 ECT 100 Z280 Same with Z 80 MPU 420 500 ELECTRONIC PRODUCT ASSOCIATES MICRO 68b 6800 MPU computer wi
19. 30 enameled wire 41 CAR BATTERY Q 2N5296 nm um joe EEE PON S000600508000205200000 0070 RUMP UUUUMUMMaEESUIEGEAAHEEeEEEEEERAEUIESMUEEEEEEEEEEEEEUEEEEEEEEEREUE ELUEESEREEEREEEEREREREEEEEU po PM gu a Lio pnaamm PARTS LIST C1 0 005 p f 500 volt disc capacitor C2 22 pf 25 volt tantalum electrolytic ca pacitor C3 C4 20 pnf 150 volt electrolytic capacitor D D2 500 volt 2 ampere silicon rectifier 1N2070 HEP R0053 or equivalent FT 250 volt SOQ watt second flash tube Radio Shack No 272 1145 or similar Q1 Q2 60 volt l ampere npn silicon tran sistor 2N5296 or equivalent R 68 ohm 4 watt resistor R2 S60 ohm l watt resistor R3 470 ohm 2 watt resistor R4 220 000 ohm 2 watt resistor 000000000000000000000000 e DI IN2069 4 a E 20pF C4 Eg 20 pF FT D2 IN2069 SPARK PLUG R3 470n TI Transformer wound on TDK Type H5A P2213 ZS2H ferrite core and TDK Type BP 2213 612 bobbin See text color coded test lead cables alligator or crocodile clips with insulated boots 2 rubber grommet printed circuit board Dow Corning Silas tic cement machine hardware stranded hookup wire No 30 and No 36 enameled wire spring type spark plug cable connec tor available from most automotive supply outlets stranded hookup wire solder etc The TDK ferrite core bobbin assembly 3 50 and an etched and drille
20. 5 way binding posts 2 for power 9 75 L x 6 6 W x 325 H 248 x 168 x 33mm weighs 5ib 2 27 Kg For 117VAC 50 60Hz 220VAC available at slightly higher cost Price 80 00 PB 203A All P3 203 features plus separate regulated 15VDC and 15VDC 0 5A supplies with internally and independently adjustable output voltage Same size as PB 203 5 5 Ib 2 5 Kg For 117 VAC 50 60 Hz 220 VAC 50 60 Hz at slightly higher cost Price 129 95 All Prices Shown are Manufacturer s Recommended List Prices and Specifications Subject to Change Without Notice LOGIC PROBE LP 1 Compact self powered multi family probe with pulse stretching and latching memory capability for DTL TTL HTL and CMOS By means of unique cir cuitry that combines the functions of a pulse detector stretcher and memory the LP 1 makes one shot IS low rep rate narrow pulses nearly il impossible to see even with a fast scope easily detectable and visible 2 Input events positive and negative level transitions pulses etc are automatically detected by the LP 1 s specially designed input aia circuits Pulses as narrow as 50 nanoseconds ae are stretched to 4 second and by simply setting the PULSE MEMORY switch to the MEMORY position single shot as well as low rep rate events can be stored indefinitely To insure long trouble free service the LP 1 incorporates a rugged high impact plastic case built in strain relef power cable rever
21. A1 and A2 LED2 turns on All the while Q1 is cut off and LED remains extin guished A high input causes LED to turn off and sends Q7 into conduction resulting in LED turning on The on time of C2 a triggerable one shot multivibrator is determined by the time constant of C and R4 which is 200 ms with the component values specified The IC is triggered by a negative going transition at pin 1 or pin 2 Any level change at the probe tip will cause this condition triggering C2 and turning on LED3 for 200 ms To prevent C2 from timing out after being triggered memory switch S1 must be closed When pin 6 of C2 goes low at the moment of triggering the signal is applied to the junction of C1 and H4 This prevents C1 from charging and C2 re mains in the triggered state Opening S7 permits normal timing to resume ELECTRONIC EXPERIMENTER S HANDBOOK Fig 1 Circuit diagram of digital probe xial cable does not require critical lo cationsolongasitis clear ofthe board and does not interfere with switch op eration Label the LED holes LO P and Ill from tip end toward the switch end of the body Then fit small rubber grommets into the tip and cable exit holes Slip over the free ends of the mem ory switch wires in lengths of small diameter heat shrinkable tub ing Solder the leads to the switch lugs and shrink the tubing over the connec tlons Over the free end of the coaxial ca ble slip a 4 in l
22. Altair bus computers RAM and PROM memory parallel serial cassette and video display inter faces and software including CUTS 1200 baud cassette bootstrap includes 2k ROM monitor space for 8k bytes additional ROM 870 With 5k RAM Kit wired 594 829 B110 With 9k RAM Kit wired 730 998 8190 With 17k RAM Kit wired 964 1163 RIVERSIDE ELECTRONIC MVM 1024 VIDEO MODULE Parallel access video display for 8080 6800 and other MPUs Displays 16 rows x 64 characters full 128 character upper lowercase ASCII with invert ed characters true blinking cursor independent of Character reversal Organized as three bidirectional O ports so requires no address lines no use of MPU registers to form memory pointer Cursor dis play is blinking over and under line Wired only Tu e Teas ME Soul Se HU a Om aes CA HOURS 225 RMQ SYSTEMS PS 1 POWER START Auto load board restarts computer at address of ROM monitor or bootstrap loader upon power up or re set Can be switched out when desired has on board switches substituting for front panel sense Switches for terminal options etc Available with on board ROM or without for use in systems with ROM Can be located anywhere in memory address space With ROM Kit wired 195 295 PS 1 Without ROM Kit wired 165 265 SEALS 8KSC 8k static memory with address select switch Kit WIG Ne
23. B RI9 20 o tes gt gt 3 m fee D NE o o o pO T A c E om C ow A as S f qa Oo St oue wm MN B et OW o pm gt g LEOI4 LEDIS o O ul 2j o m gt i cn e a D o zi oO c d o Or wo N m Ho Um uJ NMM Y zj o o ul c d E e lt e N Z Oo M s MACH Q Q O O N HON E o uj Nm c ge m eo o 2 d c MN s o uj UN or oO wv Ri R LEDI R20 ELECTRONIC EXPERIMENTER S HANDBOOK PARTS LIST SI BI 9 V battery IHi C1 C2 C5 C6 0 01 uF 25 V disc ceramic capacitor C3 0 1 pF 25 V disc capacitor LC NA as C4 2 2 aF 16 V electrolytic capacitor 7 1 IC IC2 NESSSV IC timer or equiv a i 2 S The following resistors are Y4 W 10 toler GRE tl I z i 2 E ance C EN C R5 RE R2 100 000 ohms R2 s 2 R3 2 2 megohms udi DES R4 47 000 ohms R5 4800 ohms c2 C3 C5 C6 SI S p s t switch l SPKR T Spkr 2 dynamic speaker Radio Shack E 40 245 or equiv PI Miniature phone plug Misc Suitable enclosure Radio Shack 270 230 or equiv 9 V battery clip tape or Fig 2 Audible hit indicator option When ICI is on EE x circuit board hook up wire solder etc the tone is heard from IC2 in the form of a 4 sec beep inn e E E About the Circuit The circuit is com s E z z posed of a number of timers in the mo agd Uug i e 3 gt nos
24. Kit wired sssss 19 34 LEAR SIEGLER ADM 3a DUMB TERMINAL CRT terminal 80 characters x 24 lines on built in 12 in diagonal screen Standard 64 character AS CII uppercase character set supplied 90 character upper lowercase set optional Switch selectable cursor modes Underline cursor homing to lower left of screen with automatic scrolling and page mode with reverse character cursor homing to upper left End of line tone Full and half duplex modes 11 communication rates from 75 to 19 200 baud Switch selectable RS 232 and 20 mA interface to computer extension RS 232C port for printer re corder or additional terminals 20 mA optional Cursor can be directly addressed to any part of Screen by keyboard or computer in page mode Kit Me TM Tm 875 Lowercase option sesssee eem 50 Arithmetic keypad with cable and connector 85 MICON CAPTAIN VIDEO TERMINAL Compact terminals with Teletype compatible key board power supply RS232 interface 110 9600 baud selectable speeds choice of eight colors KDM 1 With internal display one line x 32 charac IBS ocn s a E inte cae Ec de 490 KDM 2 For 16 line 64 character display on video monitor or TV set RF coupler supplied cursor e eher T qoe poer A E DEN 625 KDM 3 For 24 line 80 character display on CRT BIRO IRON Sentra ceti et CP EY 850 Pocketerm Similar to KDM 1 but with built in mo dem and acoustic coupler for d
25. Locate this lead and connect and solder it to the high voltage terminal on the flashtube Note The high voltage terminalis the metal band affixed to the outside of the flashtube Pack the connection with Silastic cement to insulate it and set the assembly aside to harden When the cement has set slide the circuit board assembly into the flash light case and anchor it in place with Fig 3 Wired pe board assembly shows T1 mounted with hardware fiber washer C4 is on top of C3 two 4 40 x V2 in machine screws Screw on the reflector assembly but under no circumstances permit there flector itself to rotate If you allow the reflector to rotate the flashtube will be damaged or a short circuit will de velop How to Use Kettering ignitions re quire that the ignition point dwell time be set to manufacturer s speci fications before timing adjustment is made This can be easily accom plished by using a dwell meter on most General Motors cars and ad justing the points with an Allen wrench while the engine is running On most other car makes the dwell angle must be set by adjusting the point gap open ing Bear in mind however that the dwell angle must always be properly set before the timing is adjusted as changes in the dwell angle will change ignition timing Locate the number one cylinder of your car s engine On 4 and 6 cylinder engines it will be the one Fig 4 Flashtube mounts in enlarged hole in li
26. OOD test equipment can cost quite a bit of money but if you are just in terested in having some relatively sim ple items and have a well stuffed junk box you can put together a few really useful circuits The basic systems described here in clude an audio generator which can also be keyed to make a code practice oscilator a simple transistor quality checker for either audio or r f an r f os cillator that can be used to align either BCB radios or their i f s and an audio amplifier that can serve as a useful au dio section for almost any experiment requiring a loudspeaker Assembled from discarded semiconductor radio parts these circuits can be put to many uses Audio Oscillator Shown in Fig 1 this circuit consists of an npn and a pnp transistor With the values shown it will produce a mid range audio tone If sock ets are used for the transistors plugging a suspect transistor in the appropriate socket will produce an audio tone if the transistor is good A conventional Morse code key can be connected in series with the positive supply at J1 and with S1 turned on and a speaker connected to the output you have a code practice oscillator You can use this oscillator to check any type of audio amplifier by starting at the speaker and working back Crystal Oscillator A simple crystal oscillator is shown in Fig 2 The crystal obtainable from any crystal supplier should operate at about 228 kHz The harm
27. aseasd suoas ad uo ssoid sour Aiayeq ioj jaututo18 193 Joqqni sIsseyd asqeuns ISIN O 9q 99S 19u110 suen indino Arurud vgr A LTI A CI CL jout10jsug1 aaup dn days 19420s ZuyjuNnow sisseys 10A 11 10S yams O1tjl 3 qnop 3 od e 1S suyo 000 0CC 8131 suyo 000 095 L Ug SWYO 0000179121 sugo OOO OC L7 S 1a wyosau p LM SLUYO 0001 O0T3l suyo Q0Z p 621 suyo ore suyo 000 01 ICW OcH EL HC UE La od suyo Qcc ccW 60H Sl suyo QOCC l sulqo 000 89 r Cal 3 54 a50 21 510181821 JUMO GOA ia3jauronusjod unqo 000 0g 1 IXW 1N Vg 1 uie3 payau sS0ENC 010 01 SO VOU ISSUE 8626 NC TO O JOSISUBD pee e NC 7 CO jojsisuen c ceNC 10 123205 JAVU Jo E L d Jajati V O0 0 0C LIN dwe do penp p 12l 3potiP 8p IPNI EIQ OIG 9PoiP OOPN L776G EG sn Jpg 19e24q 102102 Y gl AD 1oyavdeo ssip ql 0 ELF ZID 00 jopordes Mjo adAj od yoa g1 A 0001 019 Jonaedes B O peop erxe HOA 9 47 OOOI 69 ijopnogedeo on 0112312 04 91 ri 77 82 iojioede 21410112312 104 91 HTl 07C v2 sonsedes aona djo 9 Jri Lp 2 9 8 O sonsedes stp Jri 7000 72 sonoedes w H 29070 ip LiSi1Siuvd ELECTRONIC EXPERIMENTER S HANDBOOK 68 __ PC BOARD MOUNTING S OX THREE TRANSISTORS ON ONE SIDE THREE ON OTHER NOTE COMMON MOUNTING HOLES 1 32 ALUMINUM
28. bike is moving Faster speeds give greater light output than slower speeds and when the bike is stopped there is no light at all The best way to remedy the situa tion it would appear is to team bat teries with a generator This way you can extend the life of the batteries by using the generator while in motion Furthermore you get full light output when the bike is stopped because the batteries take over And that is just what the following is all about System Design You can t just con nect batteries in series with each other hook them directly across a generator and expect the system to work It won t because the impe dances of the power sources are much lower than the resistance of the light they are to power The result of such an arrangement would be to have most of the power flowing from one source to the other with the lamp re maining dark What a battery generator power sys tem needsis isolation between thetwo sources plus a scheme that automati cally switches to battery power when the output of the generator falls off and then switches back again when the generator s output picks up This IS what the circuit shown in the schematic diagram is designed to do Assuming that there is no generator power and S7 is closed diode D1 would be reverse biased Transistor Q1 is cut off as a result of an absence of base current So the generator wouid be electrically isolated from battery B1 Under these co
29. dependent resistor Radio Shack No 276 677 or similar Q1 Q2 2N3906 transistor PARTS LIST Q3 2N3904 transistor R1 R2 145 000 ohm V2 watt resistor R3 4700 ohm 2 watt resistor R4 R5 R8 10 000 ohm V2 watt resistor R6 47 000 ohm V2 watt resistor R7 2200 ohm V2 watt resistor R9 10 000 ohm 1 watt resistor RECT1 200 PIV 4 ampere minimum rectifier bridge assembly SCR 1 200 PIV 4 ampere silicon con trolled rectifier General Electric No 106B or similar SO Three wire chassis mounting ac re ceptacle T1 117 volt isolation transformer Misc Three wire line cord with plug 160r I4 gauge aluminum utility box printed circuit board or perforated board and sol der clips spacers hookup wire fuse Socket machine hardware solder etc Fig 1 Relative resistances of LDR1 and LDR2 determine operation of bistable switch made up of Q1 and Q2 1978 Edition 65 Fig 2 Actual size foil pattern for the printed circuit board is shown above The component placement diagram is at right become cut off according to which of the LDR s receives the light Once the bistable switch goes into a given state it will remain in that state as long as power is applied to the circuit until the opposite LDR is il luminated Resistor R8 determines the level of the gate voltage applied to SCRI When Q3 is saturated this gate volt age is minimum Conversely when Q3 is cut off the gate voltage is at
30. enclosure Radio l e S i o i Shack 270 231 or equiv 734 x 4 x a a 9 w ons 2 enclosure Radio Shack 270 232 or B J o e equiv 5 1 16 x 2598 x 158 enclosure T di e 9 J me P Radio Shack 270 233 or equiv four C sos 95 9 mw P So cell battery holder Radio Shack 270 390 or 96 8 o O y Ry fa equiv 12 conductor flat cable 3 feet sol b der printed circuit board ete Note The following are available from J A L Associates P O Box 107 Eaton town N J 07724 Etched and drilled main pe board specify B UP 8 95 etched and drilled set of three pc boards main Batter s Box and Sound Option specify B PKG 10 60 Price includes shipping Alow 3 to 6 weeks for delivery N J resdents add 596 sales tax e820 I C 5 CEDIS ope 9 9 en289 C28 R34 un C 5 COMMON e 5 e 4 e S6 1978 Edition 9 ee ee ee PA Etching and drilling guide for main pe board of Batter Up The schematic diagram for Batter Up is shown in Fig 1 When S1 is momen tarily depressed it triggers C1 which produces a 0 05 second wide pulse at pin 3 The pulse is capacitively coupled to pin 2 of C2 The negative edge of the pulse triggers C2 and the process pro ceeds down the line Switch S3 grounds the cathodes of one of the three LED banks and one side of either S4 S5 or S6 The grounded LED bank will light in sequence The switch corresponding
31. for L3 Coils L1 and L3 each consist of 10 turns of insulated wire wound around L2 and L4 respectively When building the receiver there are a few points that must be kept in mind Any device with a power gain of 110 dB requires careful layout of the compo nents to prevent feedback Hence keep the tuning assembly including L1 through L4 isolated from the other com ponents in tne circuit In the circuits in Figs 1 and 2 the agc action in the IC is highly dependent on the resistance of the headphones so use phones with impedances of 400 to 600 ohms When tuning the time signal only re ceiver the variable capacitors are used for coarse adjustments while the slugs in L2 and L4 are used for fine tuning Ad just them for the strongest clearest re ception of the WWV signal Making A Good Thing Better You Fig 1 With simple A M receiver local stations can be brought in easily clearly SEE TEXT Fig 2 A 15 foot antenna and tuning coils convert the circuit to receive station WWV can improve the performance of the re ceivers with two simple modifications The first is the use of a voltage regulator circuit that permits the receivers to oper ate safely from a 9 volt transistor bat tery The second isolates the IC s agc circuit from dependency on the imped ance of the phones or an amplifier into which the receiver s signal is fed Both modifications are shown in Fig 3 The lettered points connect
32. maximum The SCR is connected in series with rectifier assembly RECT and control socket SO across the power line With no filter capacitor in the circuit the negative going ac line alternations are folded up to produce 120 positive going half cycles second on the anode of SCR1 The SCR will not conduct until its gate is made positive with respect to the voltage on the cathode When this occurs Q3 will be cut off the SCR conducts and powers the electrical device plugged into SOT The SCR will remain conducting for as long as the gate voltage is ap plied to it When Q3 is triggered into saturation the SCR automatically turns off when the voltage applied to its anode reaches the zero point Then the device plugged into SO7 has its power cut off Resistor R9 diode Df capacitor CT and zener diode D2 form the low voltage supply for the transistor cir cuit Construction Building the light activated remote control system is best accomplished with the aid of a printed circuit board the actual size 66 etching and drilling guide and com ponents placement diagram for which are shown in Fig 2 Note that all com ponents with the exception of LDRI and LDR2 and SO7 mount on the com ponentside of the board The isolation transformer T1 and the fuse Ff can be mounted at any convenient point within the enclosure Start construction by mounting the components on the top side of the board putting in SO last Pay
33. mon is removed from the probe tip the LO LED should extinguish and the P LED should again light for 200 ms When 5 volts is applied to the probe tip the same thing should be Observed on the 1 LED To check for memory action place S7 in the mem ory mode and touch the probe tip to either common or 5 volts LED P should come on and remain on until 57 is returned to the stretch mode ae en Fone E NEA V Fig 2 Foil pattern top and layouts for both sides below 33 The chances are excellent that You have a talent other people are willing to pay for You re handy around your house have the ability to fix things and make them work right that s why there may be a rewarding career for you in Electronics A career in Electronics Absolutely Because you re interested in things How they work Why they work How to take them apart and put them back together Plus you ve got a head for detail work Your chances are excellent With the right kind of specialized technical training you can have a challenging financially rewarding future waiting for you in Electronics Think of the career opportunities computers aerospace 2 way radio communica tions radio TV broadcasting medical electronics to name just a few And surprisingly you don t need a college degree All you need to do to qualify for one of these excit ing career fields is to build upon the technical aptit
34. oe R9 e9 9 Rg 7 9 e Ri6 c4 9 QI i e R6 9 RIS e e D5 e G2 J e 2V e D6 9 R 3 t 9 9 RIO 9 Cl C6 We e 9 Jeo T cT e R21 9 x w R22 E c B Elc B AGC 4l2V B A Q4 Q3 l DIO DII e ee ets AGS Taam ON HEAT SINK CIO Fig 3 Etehing and drilling quide and component layout for pe board D10 D11 Q3 and Q4 touch heat sink 70 If the meter indication is correct turn off the inverter and connect a 117 voit ac meter and a 100 watt lamp to S01 Keep in mind that this is a hazardous voltage Turn the inverter on and adjust H77 to obtain 117 volts at SOf Use a frequency counter or the cir cuit shown in Fig 4 to adjust H7 for 60 Hz In using the circuit in Fig 4 adjust R1 until the neon lamp does not flash zero beat Fig 4 Use this cirenit to tune the inverter to 60 Hz Operation This equipment like any ac line powered gear must be treated with great care The cabinet should be adequately ventilated at all times The design is safe up to an ambient of 120 F If the circuit breaker trips check the ventilation and possibly re duce the output voltage slightly It is good practice not to operate any elec tronic gear in an ambient in which a human is not comfortable e ELECTRONIC EXPERIMENTER S HANDBOOK BY JOSEPH E TAYLOR Old Transistor radio parts can make Audio Oscillator Crystal Oscillator A F R F Amplifier
35. 175 LM320T 18 175 LMJ20T 24 175 LM323K 5 995 LM324N 180 LM339N 170 LM340K 5 1 95 LM340K 6 195 LM340K 8 1595 LM340K 12 195 LM340K 15 195 LM340K 18 195 LM340K 24 1 95 LM340T 5 175 LM340T 6 175 LM340T 8 175 LM3401 12 175 LM340T 15 175 LM3AQT 18 175 LM340T 24 175 LM350N 100 LM351CN 65 6 Digit 6 Digit 4 Digit B Digit 4 Digit SN7459A SH 7450N SN7470N SN7472N SN7473N SN7474N SN7475N SNT476N SN7479N SN7480N SN7482N SN7483N SN7485N SN7486N SN7488N 5N7489N SN7490N SN7491N SN7492N SN7493N 5N7494N SN7495N SN7496N SN7497N SN74100N SN74107N SN74121N SN74122N SN74123N SN74125N SN74126N SN74132N SN74136N SN74141N SN74142N SN74143N SN 4144N SN74145N 5N74147N 5SN74148N SN74150N SN74151 N SN74153N CD4040 CD4042 CD4O044 CD404B CD4047 C04049 CD4050 CD4051 CD4053 CD4059 CD 4060 CD4056 CD 4069 CD4070 CD4071 CD4081 CO 4508 CD451 CD4515 CD4518 CD 4520 M 14566 78MG LM370N LM373N LM377N LM380N LMSBOCN LM381N LM382N NESQ1K NES10A NES31H NES3BT NES40L NE5SSON NES53V NES60B NES61B NES628 NES65H NESG5N NESBGCN NE357H NE567V LM703CN LM709H LM709N LM710N LMTTIN LM723H LM723H LM733N LM739N LMT41CH LM741CN LM741 14N LM747H LMTA7N LM748H LM748N LM1303N LM1304N LM1305N LM1307N LM1310N LM1351N LM1414N 7ALSOO Fals 4 4L S75 up STR ALSH TALSE Ta SHB 741 590 4L59 741993 741 595 ALSO 74L S 0 L51039 Ka CALS332 ALS 138 74 8138 LINEA
36. 245 IMP 68X Interface for IMP1 printer see Peripherals 22 ADC 1 12 bit analog to digita converter 382 ELECTRONIC TOOL ETC 1000 6502 MPU computer accepts wide variety of processors 2 80 8080A M6800 and F8 for aiter nate or multiprocessor use Basic system includes 6502 control processor 256 byte ROM expand able on processor board to 4k 1k RAM eight digit LED display hex and contro function keys eight 1 0 device ccntro lines two serial I O lines and in terrupt system with eight levels plus choice of two power supplies Space in cabinet for up to 16 ex pans on options such as additional MPUs ROM BEY 7 WX N i i SS RAM penpheral controllers and external interface modules for real time control Memory map option allows expansion to 4M Other options include 220 V and low voltage power supplies bus expan sions and peripherals Wired 775 1000S Stretch chassis option for above 32 slot 100 1003 28 A power option 75 1011 Power on restart user addressable 55 1013 4 Battery backup 270 1023 Altair compatible bus extension for use of Al tair bus compatible modules with ETC system 90 1046 Cassette I O S65 1100 4k RAM 235 1120 8k RAM 385 1406 16k PROM module 215 1407 8080A MPU with 1k private RAM ROM 325 1408 M6800 MPU with contro ROM 255 1411 F8 MPU with ROM and 1k RAM 325 1413 6502 MPU with ROM and 1k RAM 325 1414 Z 80 MPU 299 1415 Z 80 M
37. 40 7415365 CD4025 19 CD4520 t 74LS125 55 7418366 7418126 65 7418367 eeu p pom 74181321 00 74LS368 74L 133 35 74LS390 1 75 CD4029 99 74C04 7418136 39 74LS393 1 45 CD4030 35 74C107 74L8138 85 74LS670 3 25 CD4035 99 7418139 85 RADIO HUT GUARANTEE if you are not satisfied with any of our products NO MATTER WHAT THE REASON we offer you a full money back guarantee if the prod uct or products are returned within 14 days after you receive them ORDER BY PHONE Charge your order to BankAmericard or Master Charge USE OUR TOLL FREE WATTS 1 800 527 2304 CIRCLE NO 20 ON FREE INFORMATION CARD uxE Only 5 95 each 3 for 15 50 in any combination DEL of titles including ali postage and handling charges MAGAZ Outside U S A add 1 per case 3 CHARGE YOUR ORDER TO YOUR AMERICAN MAGAZINE CASE EXPRESS BANKAMERICARD MASTER CHARGE OR DINERS CLUB ACCOUNT Ziff Davis Serv Div Dept JJ 595 B way N Y 10012 Please send the Magazine Cases indicated below TITLE QUANTITY YOUR FAVORITE ZIFF DAVIS MAGAZINES 4 CHECK O All Black J Maroon Back Black Sides O ENCLOSED 1S EEH 78 CO CHARGE 3j BankAmericard C Master Charge TUN American Express J Diners Club e The ideal way to save your valuable copies keep Wessunti 35 Exp Date them well protected and make it easy for you to Edward D Muhifeld Senior Vice President Sports Division Philip Sine
38. 50 000 000 IN STOCK John R Emery Senior Vice President Finance and Treasurer Phillip T Heffernan Senior Vice President CD4000 CD4001 CD4002 CD4006 1 CD4007 CD4009 CD4010 CMOS 19 19 19 20 Ag 47 47 19 CD4040 CD4041 CD4042 CD4043 CD4044 CD4046 CD4047 74L S08 741509 74LS10 741S11 741 S 13 741814 74185 15 74LS20 741 21 741822 74LS26 74LS27 741 830 74 832 74 537 74L 157 74LS 158 74LS 160 74LS 161 74LS162 7415163 74LS168 74L S169 7418170 7418173 74 8174 74L 175 7418190 741 191 74 8192 330 ohm 470 ohm tK ohm 1 2K ohm 2 2K ohm 3 3K ohm 4 7K ohm 6 8K ohm 10K ohm 20K ohm 22K ohm 27K ohm 33K ohm 39K ohm 43K ohm 47K ohm 82K ohm 100K ohm 150K ohm 220K ohm CD401 1 CD4049 7 ALS3B8 f 7ALS 193 CD4012 19 CD4050 74L540 74LS194 M NE CR Pa E All resistors are PC lead ass rai 251 but they are not pulloffs The leads are about 1 4 CD4015 78 CD4056 CD4016 32 CD4066 yates Dp 100 minimum order for each value CD4017 95 CD4071 7ALS74 74L 257 CD4018 95 CD4081 74LS76 74LS258 CD4019 45 CD4507 1 74LS86 74LS260 NO MIX 100 99 Value in 1 8W only 1 4W unless otherwise 741890 74L S266 CD4020 97 CD4508 74LS92 1 74LS279 specified Most are 10 tolerance CD4021 97 CD4510 1 74LS93 1 00 74LS290 CD4022 97 CD4512 1 uibs os 74LS112 49 7415295 CD4023 19 CD4516 E 74L S113 AD 741 5298 CD4024 75 CD4518 1 74L 114
39. 741 op amp IC4 555 timer Ji Miniature earphone jack M I l mA meter Radio Shack 22 037 or similar QI to Q5 2N3565 transistor Following resistors are V watt 5 R1 R2 R20 R 1 1000 ohms R3 to R5 47 000 ohms R6 R7 R14 100 000 ohms R amp 68 000 ohms electrolytic R9 R 10 R 13 27 000 ohms RI1 1 5 megohms R 12 820 ohms R 15 10 000 ohms R16 R 18 R 19 4700 ohms R 17 1 30 000 ohms R22 560 000 ohms R23 R24 220 ohms R25 R26 50 000 0hm tiometer 1 82 Dpdt subminiature switch Misc Miniature crystal or magnetic earphone and plug set of electrodes V2 stainless steel discs and electrode paste or disposable Ag Ag C types enclosure LMB 778 or similar knobs 2 two conductor shielded cable 5 ft miniature alligator clips 3 rubber grommet mounting hardware Dispos able Ag Ag C electrodes are available from medical supply houses Perma nent Ag Ag Cl electrodes are pre ferred for ease of use Small plastic containers of electrode cream are also available from medical supply houses linear poten Q2 2N3565 RI6 4 7K V2 RI2 Q3 2N3565 82on NN cr lyF RIO R9 R8 27K 27K 68K y2 I os Y 2N3565 50K IOyF INTEGRATE G MA KO RI9 4 7K MICROVOLTS RM Note The following are available from EDC P O Box 9161 Berkeley CA 94709 complete kit of parts including two disposable Ag Ag CI electrodes stainless
40. BANK TEXAS RESIDENTS CALL COLLECT AMERICARD VISA OR Money Back Guarantee NO COD s TEXAS RESIDENTS ADD 5 STATE moa 14 271 D022 TERMS 3 amp 5 TRARA ORR ONDER SO STATES TOLL FREE 1 800 527 3460 ADD 75c FOREIGN ORDERS U S FUNDS WATTS LINE ONLY FORALL YOUR CONSTRUCTION AND ASSEMBLY NEEDS WE RE YOUR HEADQUARTERS FOR THE HOBBYIST EXPERIMENTER AND THE PERSONAL COMPUTER FAN OFFERING THE BEST PRICES AND GUARANTEED PARTS 86 ORLE A NOA Mal REE E are ELECTRONIC EXPERIMENTER S HANDBOOK Using an MOS array and digital electronics eliminates vidicon and yoke OLID STATE image sensors may one day supplant vidicon tubes in TV cameras They promise small size and easy camera construction have a low power requirement and operate in a wide range of light conditions Cost however has been prohibitive until now Presented here is Cyclops the first all solid state TV camera project using a special MOS photoelement array as the image sensor and it can be built by electronics experimenters at an afford able price Any image that can be picked up by a conventional TV or movie camera can be picked up by Cyclops Unlike conven tional cameras however Cyclops is sensitive to infrared radiation and is thus able to see in the dark when an infra red light is used to illuminate the scene 1978 Editlon viOEO Amp E Fuss Re yr ta dl BY TERRY WALKER HARRY GARLAND amp ROGER MELEN
41. CA 90640 MICRO DESIGNS 499 Embarcadero Oakland CA 94606 MICROCOMPUTER ASSOCIATES 2589 Scott Boulevard Santa Clara CA 95050 MICROGRAPHICS P O Box 2189 Station A Champaign IL 61820 MICROLOGIC P O Box 55494 Indianapolis IN 46250 MICROMATION 54 Union St San Francisco CA 94133 MICRONICS INC P O Box 3514 Sreenville NC 27834 MIDWEST SCIENTIFIC INSTRUMENTS 220 West Cedar Olathe KS 66061 MINITERM ASSOCIATES Box 268 Bedford MA 01730 MITS 2450 Alamo S E Albuquerque NM 87106 MORROW S MICRO STUFF P O Box 6194 Albany CA 94706 MOS TECHNOLOQY 950 Rittenhouse Rd Norristown PA 19401 MOTOROLA Educator HEP MRO OPERATIONS DIV 785 W 22nd St Tempe AZ 85282 Evaluator EXORciser SEMICONDUCTOR PRODUCTS DIV 3501 Ed Bluestein Bivd Austin TX 78721 Micromodules SEMICONDUCTOR PRODUCTS DIV P O Box 20912 Phoenix AZ 85036 MOUNTAIN HARDWARE P O Box 1133 Ben Lomond CA 95005 M R S P O Box 1220 Hawthorne CA 90250 MULLEN COMPUTER BOARDS P O Box 6214 Hayward CA 94545 NATIONAL MULTIPLEX CORP 3474 Rand Ave South Plainfield NJ 07080 NATIONAL SEMICONDUCTOR CORP 2900 Semiconductor Drive Santa Clara CA 95051 NBL Box 1115 Richardson TX 75080 NETRONICS 333 Litchfield Rd New Milford CT 06776 NORTH STAR COMPUTERS 2465 Fourth St Berkeley CA 94710 OHIO SCIENTIFIC INSTRUMENTS 11679 Hayden St Hiram OH 44234 OLIVER AUDIO ENGINEERING INC 7330 Laurel Can
42. ERT eT ER Tre T 399 579 IMM ROM Intelligent Memory Manager control board for up to one megabyte of memory ROM ver sion KIEL WIFBd cadet eost ute EX E EROR 299 399 IMM EPROM EPROM version Kit wired e c a rx n ME m ciat e e 499 699 INTERFACES MIO Multiple I O board two parallel one serial one control port one Byte Tarbell cassette inter face Less cables Kit wired 195 350 PIO 4 1 Parallel I O with one port expandable to four ports Less cables Kit wired 93 140 PIO 4 4 Parallel 1 O with four ports Less cables Kil wirod te ae ee eta 156 299 SIO 2 1 Serial I O with one port expandable to two ports Less cables Kit wired 125 235 SIO 2 2 Serial I O with two ports Less cables Kit wrede e Ec Use Dacicus d qe 156 299 SIOC Serial I O clock piggyback board for SIO 2 1 pep M IB sc teet me uL esce 31 59 PIO6 6 Programmable six port parallel I O Less cables Kil wired dote iere EH 169 279 OTHER BOARDS PIC 8 Priority interrupt interval clock Kit wired Toc TERRACE 125 238 EXT Extender board Kit wired 39 49 GP 88 Prototyping board Kit wired 39 47 Multiprocessing and Shared Memory Write for details INTERNATIONAL DATA CLOCK MODULE Real time clock board uses 60 Hz a c line as time reference 50 Hz optional with on board crystal time base optional and extern
43. FOURTH COVER 8 EICO 105 9 ETI Products 111 10 Greenlee Tool Co 79 5 Heath Company 53 54 55 Interface Age Magazine 85 11 James Electronics 2 12 Jensen Tools amp Alloys 114 13 Kester Solder 115 14 MITS 120 THIRD COVER Martin Research 102 NRI Schools 17 18 19 15 Newman Computer Exchange 107 16 OK Machine amp Tool Corporation 98 17 OKMachine amp Tool Corporation 101 18 OK Machine amp Tool Corporation ald 19 Ohio Scientific Instrument 6 26 Peripheral Vision Inc 81 20 Radio Hut 4 21 S D Sales Co 86 22 Sabtronics 1 23 Southwest Technical Products Corp SECOND COVER 24 Techni Tool Inc 110 25 Wahl Clipper Corporation 105 ELECTRONIC EXPERIMENTER S HANDBOOK abill It Comes Naturally With The Altair 8800b The Altair 8800b tom MITS the second ger eration design the micrcccmputer thct started itall The mainirame trathas the abi ities everyone is demcnding from microcorr puters today Expand ability The Altair 8800 power suppy and one piece 18 slot mzthe boarc alow efficiert and easy expancabiliy for remory and I O options All Altair C boards e designed to give you maximum capabil tviowest power usage possible par board mie means thct for each slot use you get move eatures and require less power than with ary of the of brand Altair bus comoatible boards Whether you buy zin entire system up front cr choose to expand gradually ifs easy to get the configuratior you need wh the corm plete f
44. Goo el eene eti ves 895 EDITYPER SYSTEMS IBM SELECTRIC I O KIT Converts IBM Selectric and Selectric It typewriters for use as computer 1 0 terminals Kit includes sole noids switches clutch interconnecting circuit board harness and connector user must furnish solenoid drives and timing Optional power supply drivers and Selectric ASCII ROM available Kit IBSS Options e CMM 395 ELECTRONIC PRODUCT ASSOCIATES IMP 1A PRINTER Line printer 40 column bidirectional 5 x 7 dot matrix impact type 50 characters per second with 80 char sec bursts Prints 12 char inch on 3 in papan tone a C UE TM 450 IMP 68X Interface for EPA Micro 68b computer 22 IMP EXOR interface for EXORcisor 22 IMP ALT IMS Interface for Altair etc 79 FLOPPY DISK Floppy disk systems for 6800 MPU IBM compatible format 250k bytes per disk With cabinet and power supplies Single Drive System ooo cece cece eee cece 2595 Dual Drive System ccc eeeeseeeeseeees 3295 EXPANDOR BLACK BOX PRINTER Prints 10 char sec 80 char line uppercase ASCII 1978 Edition set on 8 in paper For friction or sprocket fed pa per parallel port Line spacing six lines inch Im pact printer can make multiple copies six max ite ce uico en diat E A deeem 296 HAL KSR ASCII BAUDOT VIDEO DISPLAY Keyboard send receive KSR and read only RO versions Choice of five level Baudot or eight level ASCII
45. Ingle wood Calif About the Circuit The receiver s cir cuit shown schematically in Fig 1 oper ates in a tuned radio frequency trf mode MOSFET transistor Qf serves as the r f amplifier stage while the Ferranti one chip radio IC IC1 provides more gain agc and detection The audio am plifier C2 delivers 0 25 watt of power to the speaker Ferritecore broadcast band antenna coil L1 and three 455 kHz i f transformers T 1 T3 with extra capaci tors tune the receiver to the 300 400 kHz band However although the sys tem covers the entire band itis basically a single frequency receiver Construction The entire receiver can be assembled on a 3 in by 2 in piece of perforated board with holes spaced on O 1 in centers Parts place ment is not critical but the general lay out shown in Fig 2 should be followed to avoid oscillations All components are mounted on the metal plate of the utility box Hence you must drill a number of holes through the plate to allow the speaker s sound to es cape Also four holes are needed for speaker and board assembly mounting and mounting must be made for sensivi ty control R6 and antenna jack J7 Al though a 2 4 in speaker is shown in Fig 2 a smaller speaker would leave enough panel space for three access holes over the slugs of the i f transform ers to facilitate tuning Use three spac ers and appropriate hardware to mount the speaker and board assembly on the meta
46. It s a full size floppy disk for the Altair Imsai plug in compatible S 100 BUS And it s available for as low as 750 00 Our floppy disk has many exciting features 91 interface card supports 4 or more drives eStores over 300 000 bytes per floppy Bootstrap EPROM included no mere toggling or paper tape 1978 Edition ON Completely S 100 plug in compatible eDrive is from Innovex the originator of the floppy concept assembled and tested eDisk operating system with file management system included on floppy Cabinet and power supply optional Also in the works are many new products we ll be letting you know about soon if you d like to take a closer look Like I O cards tape drives an impact printer all for the S 100 BUS and we re designing peripherals for a lot of other CPU s too We ve given you a little glimpse of who we are and what we re doing If you want to see more just fill in the coupon below inte SN PO Box 6267 Denver Colorado 80206 303 777 4292 Name Address City State Zip CIRCLE NO 26 ON FREE INFORMATION CARD 81 URING the past couple of years a new and fascinating hobby has sprung up computers Starting with a handful of computer freaks the num ber of hobbyists has increased consider ably and currently there are an estimat ed 26 000 hobby computers being used or at least being played with If you wander into a computer store or read computer oriented articles i
47. LAUGHLIN to switch back and forth The current meters are dual range due to the wide range of currents available Each sup ply also has an indicator light that goes on when either current or over voltage limiting occurs Circuit Operation The two low voltage supplies are identical using an integrated circuit as the regulating device Fig 1 The IC drives a power transistor OZ to provide the output current The IC contains a very stable voltage reference source and a sensi tive error detecting amplifier Regula tion is accomplished by comparing the output to the reference and any discrepancy is corrected by the error amplifier Adjustment of the output voltage is accomplished by varying the amount of the output that is fed back to the error amplifier pin 4 through R17 The reference voltage is on pin 6 of the IC It is divided by R2 and R3 and applied to the second input to the error amplifier pin 5 Lua aT m 5 6 N ES i E 6606 TE ITI thgl 5 7 Current output level is monitored by Q1 with feedback through R7 The set ting of R75 determines the amount of feedback When the feedback is suffi cient for Q7 to turn on a signal is supplied to pin 2 of the integrated cir cuit to adjust the output Voltage output is monitored by O2 with feedback through R9 The setting of R16 determines the amount of feedback and when it is sufficient to turn on Q2 Q1 also turns on supply ing the limiting signal
48. LM3505N 175 LM3909 125 LM5556N 1 85 MC5558V 100 LM 525N 90 LM7535N 125 80388 4 95 LM75450 48 73451CN 38 75452 CN 39 T5483CN 38 75454CN 38 75481CN 79 75492CN 89 THAHEN 89 RCA LINEAR CA3013 215 CA3023 2 96 CA3035 2 48 CA3039 135 CA3046 3 30 A3053 1 50 CA3058 325 CA3060 325 CA3080 85 CA3681 200 CA3082 2 00 CA2083 50 CA3085 85 CA3689 375 CA3091 10 20 CA3053 1 50 CA3102 295 CA3123 215 CA3130 138 CA3140 125 CA3600 175 RC4184 5 95 RC4195 7141 S138 A S15tf 74i thi 458157 AL 8152 PALS AG PALR TOM ALS175 a 8181 4L 190 4 5181 FAL S192 741519 7415104 aL S195 ALG 24 74L S260 14 8278 apLse7 89 95 89 95 495 95 495 6 85 9 95 Timeband s ow Watches Men s amp Ladies e Solid State e Displays hour minute second month amp day e Free set of replacement batteries e Choose LED or LCD styles e One year factory warranty TC625 White w slrap TC624 Yellow w sirap L D T249 White w bracetat 19 95 T248 Yallow w bracalat 22 95 LEO 29 95 34 95 LADIES LED TC437 White w bracelet 29 95 TCA36 Yaliow w bracelet 34 95 LCD T4 AMD VIDEO ENTERITEMAPEWT SYSTEM CHANNEL F Freeze Action e Speed Option Automatic time and scorekeeping y li Battery free AC operation Cra j S yh 5 ee Dual controls with 8 way action Channel F additional cartridges 17 95 ea Built in P
49. MP MPU 46 instructions single byte and double byte operation software controlled inter rupts built in serial I O ports bidirectional eight bit tri state parallel data port latched 12 bit tri state ad dress port Includes 512 byte 8 byte ROM with Kit bug monitor and debug program 256 byte RAM eight bit data buffer timing crystal TTY 20 mA cur rent loop interface 72 pin edge connector Kit 99 106 SC MP Il Same but requires only 5V Kit 99 mui a SC MP Keyboard Kit Hex keyboard and display for SC MP 16 keys for hex command data and address values four direct c mmand keys Kit o aa UE eni 95 SC MP LCDS Prototyping system for SC MP Inciudes power supply SC MP MPU card interfacing for other SC MP cards 20 mA TTY interface hex keyboard and display 2k RAM and 4k ROM cards also available ae rere ite ete te ec Mao on 499 SCIMP SC MP based computer kit consisting of PC boards front panel with provision for controls and hex entry pad probe and contact type and binary LED display SC MP MPU and socket RAM and other components must be supplied by user 63 NETRONICS ELF II 1802 MPU single board animated graphics com puter on five slot motherboard With hex keypad video 64 32 graphics display output 256 byte RAM 60 terminal ELF bus for expansion of memory to 64k and I O Requires 6 3 V a c Kit 100 OHIO SCIENTIFIC CHALLENGER Uses OSI bus to ac
50. NAE ic a eese Ht ee eer d s mind rg rid LEE HR F FEFA a SUE d oer Mr P a m rs LI z 1 i TO OSCH t OSCOPE eer T is m w i Pa Jacks for scope connections and onloff switch are on chassis rear f number The focal length determines the viewing angle of the camera while the f number determines how much may be supplied for use in Cyclops The two are identical except for the way pins 14 and 15 are connected to the circuit Note that on the pc board IC1 pin 15 goes to pad J and pin 14 goes to pad K If your image sensor is marked Type A connect pad J to pin 8 of C4 and pad K to pin 10 of C4 If the image sensor is marked Type B connect pad J to pin 9 of C4 and pad K to pin 11 of C4 Lens Selection Almost any movie camera lens will work with Cyclops The two important factors to consider in choosing alens are focal length and INTENSITY INPUT Fig 5 This circuit can be used if scope has no internal provisions for intensity modulation 1978 Edition light can be collected The lens used with Cyclops should have a variable aperture so that the f number can be adjusted to suit the lighting conditions The minimum f number when the aperture is wide open determines the lowest light level at which Cyclops will operate An f 2 8 lens should be adequate for most ap plications though some additional lighting may be required for indoor operation We purchased an u
51. Ne 375 M68MM04 8k ROM PROM Convertible to 61k oU VER AES VE SU DUAE RE ee eee eene 210 M68MMO04 1 16k ROM PROM 230 M68MMO6 2k static RAM o o sss 280 M68MMO5A Eight channel 12 bit differential input AJ Dimodule ores eres cu oars Treen DL o 725 M68MM058 16 channel 12 bit single ended input A Dimodulg eos ML N 725 M68MMOSC Quad 12 bit D A module 725 EXORCISER SERIES MEX6812 1 2k memory s sss 350 MEX5815 8k dynamic memory 695 MEX6816 1 16k dynamic RAM 1195 MEX68RR PROM RAM module 16k ROM 512 bote AMD comen t OE 395 MEX6820 1 O module sseeesesss 375 MEX6850 ACIA serial 1 0 ooo eee 375 MEX68WW Wire wrapped module 59 MEX68XT Extender module 79 MEX68PP1 PROM programmer module 595 MOUNTAIN HARDWARE PROROM 8k ROM RAM programmer board Hoids 7 5k EPROM 6834 plus 12k RAM for stack or scratch pad On board PROM programmer requires no spe cial software and can program from 1 to 7 5k bytes at once Includes RAM plus one PROM with 8080 FIDE coe v ca eec as ER 164 AM6800 MPU 6800 microprocessor board for Altair bus comput ers Allows conversion to 6800 or alternate and si multaneous use of both 6800 and 8080 or Z 80 processors Kit wired sss 150 130 AM6SO0K Kit l
52. Radio Shack 275 1385 or similar S2 Dpst switch S3 S4 Normally closed momentary action pushbutton switch Misc IC socket s battery holders Ra dio Shack 270 384 battery clips suit able enclosure LMB No N463 mounting hardware rubber feet 4 wire solder etc Fig 1 IC2 forms a linear rectifier for the meter while IC1 is a voltage follower to give high input impedance Photo shows how components were laid out in prototype Set S1 to a range suitable to meas ure a voltage known to be accurate voltage reference or battery and ad just R16 until the meter indicates the known voltage Disconnect the refer ence and rezero the meter with R13 and H14 Repeat these last two steps until calibration and meter zero are obtained The last part of calibration should be repeated if the meter tends to drift because of temperature effects on IC1 This drift will be about 1 50 of the meter range After calibration if the meter has been out of operation for some time the drift will cause an up scale deflection when the Minivolter is first turned on Do not re adjust for this condition it will disappear after a few minutes of warm up To balance the polarity of indica tion alternately apply the known dc voltage to the input and operating the appropriate switch adjust R75 to remove half of the difference of each reading Do this until both readings are the same to insure the indepen dence of polarity at the
53. S1 is depressed and let go When you build the thaw alarm care fully solder thin wires to TH1 Make these wires long enough to reach the cir SONALERT THI cuit proper located atop or somewhere near the freezer After first insulating the soldered connections at TH1 slip a length of insulating tubing over the probe assembly Pack both ends of the tubing with silicone rubber caulking compound When the caulk sets place the probe assembiy in the freezer o ELECTRONIC EXPERIMENTER S HANDBOOK WALKS a COSE LOOK alt Peripheral Vision is a young fast moving company that s dedicated to selling reasonably priced peripherals for various manufacturers CPU s So now when you build ycur microcomputer system you ll know where to look for all the peripherals that will make your system do what it s supposed to do Peripheral Vision may be young but we have some old fashioned ideas about how to run our business We know there are serious incompaticzilities among the various manufacturers peripherals and CPU s We want to get them together And we want to bring significant new products to market products consisting of everything from adaptation instructions kits for hardware and software to major new designs Most important to our customers Peripheral Vision is committed to helping you get along with your computer We ll do all we can to make it easy Our first product is a real reflection of this philosophy
54. Static Memory ssseeemeee 189 8k RAM Static Memory aeree 299 Expansion chassis with 10 slots for memory or I O EXPANSION oe ce Ic E LE 350 Basic chassis for use with KIM 1 320 DATAC ENGINEERING DATAC 1000 6502 MPU computer card with touch pad data and control entry no moving parts binary LED display TTY I O monitor in ROM 1k RAM sockets for 2k PROM cassette and serial interfaces two parallel O ports power on reset or restart Buffered bus on 72 pin edge connectror for external expansion With power supply 1000 1 cites es Eiern 185 1000 E Same with TIM monitor 345 THE DIGITAL GROUP Z 80 Versatile muiti option computer based on an exclu sive bus structure permitting interchangeable CPU cards Z 80 8080A 6800 and 6502 MPU cards are currently available System prices below for Z 80 deduct 50 for 8080 or 6800 100 for 6502 Many configurations available items below are just sam pling Z80 3BD 2 80 system with 2k memory plus video cassette and four port parallel I O Kit wired ert 475 695 Z80 4BD Same with 10k memory 675 945 Zz80 SYS1 Same with power supply 12 A larger motherboard nine slots and cabinet Kit wired acu MEL ere MM ELTE eer 895 1295 Z80 SYS3 Same plus keyboard 9 in video monitor and digital cassette system in cabinets Kit wired M 2045 2545 Nazis ge Mn rahe
55. V watt resistor R15 10 ohm watt resistor S1 Spst switch part of R6 SPKR Miniature speaker 8 16 45 or 100 ohm impedance T1 T3 Miniature 455 kHz i f transformer yellow core available in Radio Shack 273 1383 assortment or individually from Mouser Corp 11511 Woodside Ave Lakeside CA 92040 as Part No 801F101 Misc 4 x 2 x 1 Bakelite utility box with metal cover Calectro No J4 725 or similar perforated board and solder clips battery connector spacers control knob hookup wire solder machine hardware etc 12 volt ce 16 volt electrolytic Fig 1 Receiver operates in trf mode Transistor Q1 provides r f amplification IC2 is the audio amplifier Added gain agc and detection supplied by ICI 63 The station identifications given on You can build a compact portable the FAA channels consist of two or three FAA weather receiver with the aid of the letters in tone modulated code The rest Ferranti ZN414 linear integrated circuit of the broadcasts are spoken In tests this receiver provided good re Front of receiver has holes drilled for antenna jack speaker and sensitivity control Fig 2 Follow parts layout shown in photo to minimize the chance of oscillations occurring Photo shows how perforated board with the components 1s attached to the front panel 64 ait d ception with its built in antenna within a 125 mile radius of station IGD in
56. WINNER e2eeeeoeed ay TUG OF WAR ue A i US 8 i T gen e s FRI Eun deu ISTE e a og PY ee Toe ge Snail ebd La zz ms has E ELECTRONIC EXPERIMENTER S HANDBOOK p 4 Bie i eria fies BTIRT EP 1 7 3 3 p Fig 1 Clock oscillator IC1A drives IC2A and IC2B to generate two successive gate intervals Output of ICIB is 4 3 s pulse inverted to a 0 7 s pulse by IC7A Upldown counter 1C5 and BCD to decimal circuit IC 4 drive LED s PIN 5 ICIA CLOCK we Fig 2 Timing diagram shows relationship between pulses at X Y and Z If a player operates switch before LEDI is lit during t1 he is penalized 1978 Edition I PARTS LIST C1 CS 10 pF electrolytic capacitor C2 C6 C17 C19 to C23 0 01 uF capacitor C3 C4 C8 CII l pF electrolytic capacitor C7 C10 C13 C14 C15 C16 C27 C28 0 l pF capacitor C9 C12 0 00l pF capacitor C18 Not used C24 C25 C26 47 pF 15 vol electrolytic Capacttor C29 2 2 uF electrolytic capacitor C30 500 10004 F 15 voit electrolytic capa citor Di to D8 amp IN914 diode D9 to DI2 1N2071 diode IC1 1C8 1C9 5564 dual timer Signetics 1C2 558B quadruple timer Signetics 1C3 IC7 7400 quadruple NAND 1C4 8251B BCD to decimal Signetics C5 74192 up down counter 1C6 8241A quadruple exclusive OR Signet ICs IC10 LM309DB 5 volt regulator Si
57. be used with an ordinary portable AM broadcast band receiver The radio already con tains everything but the sensing oscillator circuit The necessary oscil lator and sensing loop are easily added How It Works The schematic dia gram forthe sensing oscillator is shown in Fig 1 Essentially it is atuned gate field effect transistor Q7 oscillator Variable capacitor C2 permits the cir cuit to be tuned across the middle fre quencies of the AM band The sensing oscillator is first tuned exactly to a broadcast station which must be done far away from any metal objects Subsequently any metal in the vicinity of the sensing loop L1 will change the oscillator s frequency to produce a beat note at the receiver s speaker Moving the loop away from the metal will cause the beat note to cease Construction The oscillator circuit can be built into any 3 in by 2 in by 154 in metal utility box To simplify 1978 Edition LOW COST METAL LOCATOR assembly use a piece of perforated phenolic board and solder clips to mount the oscillator components as shown in Fig 2 Referring to Fig 3 machine the top half of the utility box and mount on it B7 in a battery hold Fig 1 Schematic of sensing oscillator that beats against any broadcast band receiver er C2 J1 and S1 Then mount the board assembly with 6 machine hardware and in metal spacers Refer back to Fig 2 and interconnect the chassis moun
58. can be mounted anywhere convenient on the bike such as a carrier or a mud guard If you have a racing type bike that has neither carrier nor mudguard mount the lamp assemblies on the rear wheel fork struts but take care to avoid interfering with brake and shift cables e C3 1000 pF ICYCLING on our roads Can be a hazardous proposition es pecially at night when visibility is drastically reduced Manufacturers of bicycles try to circumvent the poor vis ibility problem by providing reflectors at strategic locations on their bikes to make them visible after dark The problem with reflectors is that they depend on an outside source of light to render them and the bike on PARTS LIST C IS uF 25 volt electrolytic capacitor C2 90 01 uF 25 volt disc capacitor C3 1000 WF 25 volt electrolytic capa citor DI D3 IN4001 diode D3 12 volt watt zener diode Motorola HEPZ 0415 or similar 1 L2 63 auto backup lamps IC 1 555 timer integrated circuit K1 6 volt 500 ohm relay Archer No 275 004 or similar R1 1000 ohm V watt resistor R2 100 000 ohm V2 watt resistor Misc Suitable enclosure red lensed tail light assemblies see text pc or perfo rated board 6 volt 3 3 to 6 6 watt generator if you don t already have one rubber grommets hookup wire solder machine hardware erc ELECTRONIC EXPERIMENTER S HANDBDDK TWO SAFETY NIGHT BIKING which th
59. chosen the NRI way as the right way to get ahead Read how you learn at home from bite size lessons progress ing at your own speed to your FCC license and then into the communications field of your choice There s no obligation and no salesman will call If card is missing write to NRI NRI SCHOOLS McGraw Hill Continuing Ji Education Center n NM Wisconsin Avenue n Washington D C 20016 19 W TO PROGRAM READ ONLY An experimenter s guide to programmable ROM s what they are and practical applications for them ROGRAMMABLE read only mem ories are unique among the dig ital integrated circuits readily avail able to experimenters What makes it unique is that itis user programmable You decide what you want the PROM to do and program it to do just that The only tools you need area pair of regulated power supplies some Switches and a resistor The pro gramming procedure itself is outlined later on in this article The PROM is one member of the standard ROM family of memories Once it is programmed its memory is ronvolatile which means that if rower is removed from and then reap plied to the PROM thestored informa ton remains intact By contrast a HAM random access memory has a volatile memory if power is inter rupted when it is again applied what ever information was stored in the memory will be erased The ROM and PROM can be made from bipolar transistors in w
60. data Uses 8080A for full cursor positioning and editing capability KSR display 1152 charac ters in 16 lines of 72 Has RS 232 and current loop ports Baudot from 45 baud 60 wpm to 100 baud 132 wpm ASCII from 110 to 1200 baud Has 6 1 MHz bandwidth 1 V EIA video output CRT with 11 inch diagonal 5 x 7 dot matrix Keyboard 52 key ASCII shift control N rollover Quick Brown Fox test message programmable character string to 255 characters Bell tone provided Scrolls from top down full cursor control word wrap around DS 4000 KSR ASCII VIDEO DISPLAY TERMINAL Serial ASCII eight level code Has RS 232 and current loop ports KSR version 110 to 1200 baud 150 baud available on RO model Word format is ASCII 10 or 11 unit code parity odd even or mark Video 1 V neg sync 6 1 MHz bandwidth timing is crystal controlled Display is 1280 characters in 5 x 7 dot format 16 lines by 80 characters per line 11 in CRT Has 8080A processor for full cursor control and text editing Transmission modes are character by character line block al switchable Printer inter face is RS 232 level Bell tone is provided Key board is 52 key standard ASCII with shift control N rollover DS 40005 Loose ord estilos 1195 RVD 2110 MONITOR TV Solid state 9 in diagonal screen BNC connector for 75 ohm video input As TV operates on all chan NOISE sous ck Dite END ocn ee 150 RVD 910 VIDEO MONITOR Solid state 9 in dia
61. directly under the lug of the regulator Once wired the board can then be se upper right hand corner of the board The two rightmost pads accept the 6 3 volts ac from the off board transformer for the video output with the leftmost pad for ground and the pad next to it for carrying the video signal to be connect while the third pad is connected to an ed to the CRT monitor or converted tele earth ground The two leftmost pads are vision set 5V S4 All RUN s RUN R3 5 390 TiVC5 e5yE LOAD N2 LOAD SC1 DMA IN Fig 5 Because the caleulator type control suicitches as spst the original front panel is slightly modified MP MEMORY PROTECT 1978 Edition ELF Connector Name 1802 pin e 5 volts 4 5 volts 6 Clock 1 8 Clock 39 10 LOAD 2 12 DMA IN 38 14 RUN 3 16 DMA OUT 37 18 Q 4 20 INT 36 22 SC1 5 24 MWR 35 26 SC 6 28 TPA 34 30 MREAD 7 32 TPB 33 34 D7 8 36 A7 32 38 D6 9 40 A6 31 42 D5 10 44 A5 30 46 D4 11 48 A4 29 50 D3 12 52 A3 28 54 D2 13 56 A2 27 58 D1 14 60 A1 26 62 D 15 64 Ag 25 66 EF1 24 68 N2 17 70 EF2 23 72 N1 18 74 EF3 22 76 N 19 78 EF4 21 80 GND 20 82 GND 20 84 not conn 86 3 58 MHz Note Odd numbered pins on left side of connector with the exception of pins 1 and 3 which are 5 volts are not used at this time Fig 6 The Elf bus structure enables easy system expansion 95 6 3V AC 400mA C2 tOOO
62. elsewhere Drop in on the stores speak to the employees pick up some free brochures and read Imsai 7 80 CPU BOARD RAMS 21L02 500ns 8 12 95 21L02 250ns 8 15 95 2114 4K 14 95 1101A 256 8 4 00 8212 1 O Port 3 50 8214 P lI 2 12 95 8216 Non Invert Bus 4 95 8224 Clock Gen 4 95 8226 Invert Bus 3 95 FOR 4MHZ ADD 10 00 Complete kit 149 HARD TO FIND PROMS RAMS CPU S MICROPROCESSOR SUPPORT CHIPS TTL DTL HLL ITT SERIES 300 LINEAR LEDS amp LED DRIVERS ITT SERIES 500 PLUS A COMP COMPLETE LOW POWER SCHOTTKY SERIES CPUS Z 80 includes manual 39 95 Z 80A includes manual 44 95 8080A CPU 14 95 8008 CPU 6 95 8228 Sys Controller 8 20 8251 P G I enim eoo T OD 8255 P P I SHE rp 13 50 8820 Dual Line Recr 1 75 1 25 8830 Dual Line Dr S D SALES CO Po Box 28810 EX DALLAS TEXAS 75228 Altair A Compatible Kits Dealer inquiries welcome on these items 4K LOW POWER RAM FOR 250 NS ADD 10 00 The Whole Works MICRO PROCESSOR SUPPORT CHIPS 89 95 PROMS 1702A 1K 4 95 10 40 00 2708 8K 25 00 5204 4K es 7 96 828129 IK 2 ee ee ee 2 50 8838 Quad Bus Recr 2 00 74LS138N 1 8 Decoder 99 8197 Hex Tri St Buf L 1 25 1488 1489 RS232 1 50 TR1602B Uart Du 6 95 CALL IN YOUR
63. hardware etc Double quantity for two channels ELECTRONIC EXPERIMENTER S HANDBOOK 4 watt on 4A Gl n RELATIVE OUTPUT ACROSS SPKR 2 4 6 8 1 0 INPUT VOLTS RMS Fig 2 Graph shows how compander expands or compresses the relative output across speaker hooked up between your preamp and power amp or through the tape monitoring circuit A Compander is not to be confused with devices such as tone controls and equalizers which alter the frequency response of a sys tem Circuit Operation The heart of the compander circuit Fig 1 is an opto isolator 0 1 which contains a light emitting diode and a low distortion photocell in a light tight plastic en closure This unit has much faster re sponse time than devices using an in candescent lamp often used in com panders It also introduces less dis tortion and has the advantage of pro viding a slight slow release action to enhance the expansion effect The audio signal at the speaker ter minals of the amplifier is applied to connector J7 The level is controlled and reduced by H1 R2 and R3 with diodes D to D3 acting as voltage limiters to protect the LED s The signal levelis monitored by LED1 The brightness of the LED in O 7 varies with the signal causing the resistance of the photocell to vary The power supply provides a small dc voltage adjusted by A710 to keep the two LED s within their conduction range This prevents a sudden sn
64. in requires a paper tape reader an audio cassette recorder and interface or a floppy disk system all of which are available for mi crocomputers Both audio cassettes and floppy disks allow the user s own pro grams to be recorded and stored for fu ture use too programs can be stored on paper tape as well but paper tape punches are slow and noisy and unless built into a Teletype expensive so they re less frequently used in home systems Cassette systems are reason ably fast can hold quite a lot and cost comparatively little so they re the most popular Floppy disks have the advan tage of faster access the disk s play back head can zip across the disk to get to an inside track while a cassette s whole tape must be wound past the head to get at the last part of the record ing but disk or diskette systems are expensive Between these stand mini floppy disk systems using smaller low er capacity disks about one third the capacity at about half to two thirds the system price and digital cassette units whose tape movements controlled by the computer can be quite rapid Conclusion After reading this brief in troduction to hobby computing we hope that the reader has gained some under standing of this new and exciting hobby If the interest has been fanned what is the next step Scattered about the country and in many overseas areas are several hun dred computer stores and computer clubs see listing
65. is turned on The pulse also trig gers C2A and C7B The former is a one shot multivibrator whose on time is determined by R4 and C3 Since this timer is edge triggered and the state of the trigger has no effect on the output pulse C2A can be coupled to C2B to provide a second pulse of equal duration determined by R6 and C4 The outputs at points X and Y are sequential pulses of equal duration When C1B is triggered it produces a one shot output pulse of about 4 3 seconds determined by R8 and C5 This pulse is inverted by C7A to pro duce a pulse of about 0 7 second dura tion just prior to each clock pulse The pulse at point Z is used to penalize the player who attempts to anticipate the clock and jumps the gun The timing diagram in Fig 2 shows the sequence of events The circuitry for the players is shown in Fig 3 The two circuits are identical except that their outputs are reversed to enable one to drive an up down counter C5 in Fig 1 in one direction and vice versa The players positions are keyed around one shots IC2C and C2D To see how the circuits work as sume player B does not touch his but ton when theGo light comes on or that playerA is very fast and is able to press his button during time period t2 Fig 2 Then the pulse generated by C2C Is applied to an AND gate with the pulse from point Y Two exclusive OR gates IC6A and C6B act as a frequency doubler and provide two pulses at poin
66. load ers BASIC floppy disk operating system I B080 Basic computer system Kit wired rcr 699 931 I 8080 OEM Same without front panel Kit wired Io cc ec ech hale IE CM 629 731 8048 SINGLE BOARD CONTROL COMPUTER Single board computer for control and similar ap plications Includes 8048 8748 MPU 24 pad hex adecimal keypad nine digit LED hex display 12 I O lines with handshaking 14 other VO lines five heavy duty relays RS 232 and cassette interface Monitor in ROM or EPROM optional Requires 5 6 V Includes 1k byte RAM memory sockets for 1k bytes additional RAM and 2k of ROM EROM ex pandable to 64k RAM off board ROM Version Kit wired 249 299 RAM Version Kit wired 399 499 5 V Power Supply essere enean 99 INFINITE UC 1800 For training or evaluation uses RCA COSMAC 1802 MPU 16 key hex keyboard digital hex display of address memory contents I O port front panel control of interrupt OMA I O flag 256 byte RAM expandable to 65k bytes of RAM or ROM internally crystal controlled clock parallel and serial 1 O data line capability special circuit saves memory content when unit is turned off seessssss 495 Option 001 Automatically recharged internal battery aliows program memory to operate up to four hours after power failure eesseeeeeennme 25 UC 1800K UC 1800 less
67. logic 1 is to be written into the PROM s memory the fuses must be blown The procedure for blowing se lected fuses is called programming It can be performed with the circuit shown in Fig 2 The 5 and 12 5 volt power supplies must be regu lated Switch S7 is a two circuit push button switch with one set of contacts normally open and the second set nor mally closed Switch S2 is a dpdt slide or toggle switch while switch S3 must be a non shorting rotary switch with eight or more positions After wiring together the Fig 2 cir cuit program the PROM as follows 1 Set S2 to the BURN position Note Never operate S7 when S2 is set to BURN 2 Feed the proper logic 1 5 V and logic Q 0 V or ground code for word one onto address lines A through A via S4 through S8 3 Set S3 to the first PROM output line position in which a fuse is to be blown according to your program ming truth table 4 Depress S7 for about a half sec ond and release This action in blow ing the fuse develops considerable localized on chip heat so do not depress S7 for longer than a full second 5 Allow several seconds of cooling down time for the chip 6 Set S3 to the next output line in which a fuse is to be blown 7 Repeat steps 4 and 5for each out put line in which a fuse is to be blown 8 Set S4 through S8 for the logic required for word two 9 Repeat steps 3 through 10 Continue to address the PROM for each succee
68. lowered by the activat ed photocell Best results can be ob tained by actual experimentation Power Generators Photovoltaic cells are used primarily as sources of dc power An excellent application is in the generation of power for emergencies As shown in Fig 5 silicon or selenium cells in series can furnish charging cur rents to a secondary battery with cur rent blocking diodes to protect the cells from reverse current The ammeter op tional indicates the total amount of charge Since the output of the cells is gov erned by the amount of ambient sun light special allowances must be made in computing charging rates and effec tive load resistances In typical applications solar batteries act as trickle chargers for conventional batteries that furnish high dc power 100 A or more for a few minutes at a time This concept is used in satellite applica tions with silicon photocells assembled in arrays on the satellite An excellent hobby project is the sun powered emergency radio receiver shown in Fig 6 It is simple and reliable with a 1 5 volt standby battery C or D cell for sunless days For use on land or at sea the receiver works best with a true earth ground and a long antenna The ground can be a metal frame or a submerged metal plate in the case of a boat A small transistor amplifier can be added to improve the power output Wir ing and layout are not critical but the electronic components should be
69. memory eeeesssssseme 179 KIM 3 Sk static memory esses cm 289 KIM 4 Motherboard Interfaces KIM 1 with up to six system expansion modules with all required buffer ing motherboard not required to interface KIM 1 with a single expansion board Includes 5 V 12 V regulators external power supply required 119 MOTOROLA EDUCATOR II 6800 MPU computer kit contains 128 byte RAM expandable on board to 256 bytes ROM monitor including cassette and cassette search routines plus routines to test the finished kit Aluminum case has control and data switches and tape I O jacks Edge connectors on PC board for system expan sion keyboard video display card rack memory modules and cassette programs planned Kit See ee NN meme roe 170 Additional 128 byte RAM a sese 19 Educator Il Power Supply Kit 5 V t 1 30 M6800 EVALUATION KIT Il 6800 based system with one parallel I O port one audio cassette interface 24 key hex keypad with seven segment hex displays 256 byte RAM ex pandable to 65k 1k ROM containing J Bug hex monitor Will also accept Motorola Minibug I or III monitors in place of J Bug for use with TTY or RS 232 terminals up to 3k additional ROM or PROM can be added Wire wrapping space provid ed buffering may be added for compatibility with EXORciser modules Requires 5 V 2 A power sup Dive MEKG800D2 M Cou in aoc 52 Jb MICROMODULE SYSTEM 6800 MPU modular system ful
70. meter input Use and Applications After turn ing on the Minivolter allow a couple of minutes for the IC s to warm up noting that the meter goes to the zero mark If it does not do so after a reasonable period adjust R17 to ob tain a zero Make this adjustment with S1 in the 100 V position One can think of many unusual uses for the Minivolter Here are some examples e it can measure the voltage across a junction of dissimilar metals when heated thermoelectric effect or the voltage generated across a conven tional glass enclosed semiconductor diode when exposed to light Voltages across a solder joint or connector can be measured for either an ac or dc drop with normal current flowing through the circuit e With a loop of wire connected across the input the Minivolter can be used to trace stray magnetic fields from power transformers power lines hidden tn walls etc e By connecting the Minivoltor across an unknown resistor having a 1 mA current flowing through it the instrument becomes an ohmmeter with readings down to 0 02 ohm e Switching to the 500 uV range the Minivolter can be used as a 1 HA meter having an internal resistance of 500 ohms It can measure currents down to 10 nanoamperes e ELECTRONIC EXPERIMENTER S HANDBOOK AN IGNITION TIMING LIGHT FOR IMPROVING GAS ECONOMY OWADAYS everyone knows how important it is to get the best gas economy possible from an au tomobile One of
71. permitting a footswitch plugged into SO3 to be used to turn on the enlarger lamp via K1 This feature frees both hands for the job of focusing and composing the projected image The automatic exposure controller is extremely linaar in its performance With the components specified the timing range is from 1 second to more than 2 minutes which more than covers the various paper speeds Also the system is insensitive to line voltage variations Construction For the sake of neat ness and convenience it is suggested that you assemble the controller on a PC Fig 8 View of completed controller Bracket holding the LDR sensor is at extreme left Fig 4 Photo shows inside of prototype chassis with bottom removed board see Fig 2 for etching and drilling guide and components placement dia gram The prototype was assembled with two PC boards one for the main cir cuitry and the other for the bulky C3 C4 and C5 capacitors However you can obviate the need for the capacitor board by joining one lead of each capacitor in common slipping a length of insulated spaghetti over the common lead and soldering this lead to the hole marked C3 on the main board The free leads of C3 C4 and C5 can now be soldered di rectly to their respective S3 lugs Aside from the normal precautions to be taken with any solid state circuit as sembling and wiring the PC board is simple If you elect to use perforated phenolic board constru
72. power supply not included OFT 1 Plotter kit 11 x 17 drawing area 750 DFT 1M Mechanical system only 625 DFT 2 29 17 X 22 ooo reso erener 895 770 DFT 3 3M 22 x 34 sees 1200 1025 PPS 24 Power supply 24 V 1 5 A regulated 25 SYNETIC DESIGNS FDS 2 FLOPPY DISK Dual disk system 256k per disk with IBM compati ble format Text Editor assembler and Executive Handler for I O and vector Controller can handle up to two additional drives Wired 2600 U S ROBOTICS M 5 AUTO ANSWER MODEM Allows connection of microcomputer to telephone line answers incoming calls allows terminal to computer or computer to computer data transfer RS 232 and 20 mA serial interfaces standard tele phone jack Maintenance contracts available Oper ates in originate and answer modes 105 VIDEO TERMINAL TECHNOLOGY VT 4800 TERMINAL CRT terminal displaying 48 lines x 80 characters upper lowercase with complete cursor control Has 4k bytes internal RAM expandable to 16k dis play scrolls up and down through up to 16k charac ters before any data is lost Has selective clearing controls selective video inversion page increment and decrement Interfaces to RS 232 serial TTL se rial or parallel 1 O Selectable 110 9600 baud VT 4800 MICRO Single board with parts Kit wired Ac LE ETA Dd dee 395 495 VT 4800 MINI Includes board parts
73. quality recorders both Tarbell format modifiable for Kansas City format 27 bytes sec With Triple I Phi Deck 1000 bytes second 10 in sec Extra status and control lines available for use with computer controiled drives such as Phi Deck or multiple tape recorders with Ro Che controller see Peripherals Includes soft ware room for user developed circuits Kit wired NENNEN M en Benedi D 120 9175 TECHNICAL DESIGN LABS ZPU CARD Z 80 CPU card Dual on board clocks one crystal controlled 2 MHz for system cards requiring that speed one variable to fine tune system for max imum performance Requires 8 V 600 mA Runs Z 80 and most 8080 pa dip Kit wired maii 269 345 TDL SMB SYSTEM MONITOR BOARD Combines ail basic support needed for 2 80 sys tem 2k ROM ZAPPLE monitor 2k RAM three seri al I O ports two RS 232 20 mA one 1200 baud mem o TCL audio cassette interface one eight bit parallel I O port power on restart Kit wired 295 395 TED REAL TIME CLOCK Time of dey clock connects to TTL parallel O port of any computer system requires 5 12 V Push button time setting can run off separate power sup ply or battery crystal controlled Wired only 40 VAMP TRVM 1 VIDEO ADAPTER Television modification kit for direct video input In cludes transfer switch for normal TV reception By passes turer and IF sections 10 MHz bandwidth al lows up tc 64 characters
74. screws that carry the video output and ground be sure that you connect ground to ground DO NOT use any i p 09909599001 5 wil 85998 d ELECTRONIC EXPERIMENTER S HANDBOOK o A14 wT il alyy ris 1 k4 9 o o Aa Wiii Lu L1 A15 1 C8 6 ad A3 b Gub G9 GS0G0E j 6080 e j mmm mm m o 2 Q x a ox C10 c9 d DEEP e TENE z KEY PAD S595 520 OPTIONAL IF T1 GREATER THAN 6 3V Fig 8 The Elf II uses a double sided plated through single pc board having the foil pattern shown here reduced to V size The figure also shows component placement mma 3 v a Qo 4 R26 A13 b R2 m o A16 A15 eee eo osor Qe a C10 A 8889590805 eee ee a aa mma ERm L 4 ite l 1978 Edition 37 98 PROGRAM 2 VIDEO TEST Memory Location Data Start 0000 90 B1 B2 0003 B3 B4 0005 F8 2D A3 0008 F8 3F A2 0008 F8 11 A1 000E D3 Return OOOF fe 0010 70 interrupt 0011 22 78 0013 22 52 0015 C4 C4 C4 0018 F8 00 BO 001B F8 00 AO Refresh OO1E 80 E2 0020 E2 20 AO 0023 E2 20 AO 0026 E2 20 AO 0029 SC TE 002B 30 OF Main 002D E269 002F OF 2F 0031 6C A4 0033 37 33 0035 JF 35 0037 6C 0038 54 14 003A 30 33 form of modified ac dc TV set unless it uses a line isolation transformer With the CRT monitor connected and power applied a raster should be seen on
75. sired combination RAM An abbreviation for Random Access Memory this IC contains a large number of flip flops arranged sc that a computer can address any block of flip flops within the chip During the 1978 Edition write cycle the selected block can be set up with a particular digita combina tion to be stored and during the read cycle those selected byes can be read out of the FAM usually without de stroying the data held in tne RAM There are two types of RAM static and dynamic Static RAMS use conven tional flip flops that will remain ir the set up State as determined by the program as long as their operating d c power is applied They change states only when told to by another write signal Dynamic RAMs also use flip flops but with a difference Once the flip flops have been set up as desired they will remain in that state only as long as a tiny capacitor within each flip flop remains charged To maintain the stored data the charges in these tiny capacitors must be refreshed from time to time If the refresh stops the capacitors dis charge and the flip flops car assume rendom states and thus lose the data Dynamic RAMs are faster than static RAMs and usually do not require as much operating power The payment for this is that the processor or some other circuit must take time out to per form the refresh Both types of RAM are volatile that is the flip flops will remain in the select
76. sparse mode all eight bits of each byte are mapped no interbyte or in terline spaces OMA controller allows display to change with every screen refresh information on screen not blanked while being modified I O Pro vides parallel input port with power to run most key boards one serial port ROM two sockets provided for 1k 2708 PROM or ROM or 2k ROM firmware available plus 256 byte RAM for Merlin scratch pad and stack Monitor Editor See under MBI and MEI below Interface consists of two back to back mounted boards occupying one Altair bus slot MERLIN as above Kit wired 269 349 M320 Super dense graphics add on 39 54 MCAS KC 2 1500 baud Tarbell cassette interface add on requires MEI ROM Kit wired 29 43 MSEK Serial I O expansion kits expands MERLIN to three parallel inputs three parallel outputs Jue o PATER Mm 45 75 MC IO Combines MCAS and MSEK on one PC board designed to be housed in keyboard enclo 1978 Edition SUrB RWI a a UT 67 99 MBI Merlin Basic Intelligence 2k ROM monitor edi tor for Merlin plus 256 byte RAM Provides turnkey monitor cursor control wraparound scrolling text editing Easily interfaced to BASIC or other monitors MEI Merlin Expanded Intelligence ROM with cas sette MCAS routines extended edit and monitor commands graphic subroutines ssss 35 ROM EROM 8k 2708 board also for up to 2k ROM wit
77. stainless rule hex key set scissors 2 flex ible files burnisher miniature soldering iron solder aid coil of solder and desolder ing braid Highest quality padded zipper case 6 x9 x 1 34 inside Satisfaction guar anteed Send check company purchase order or charge BankAmericard or Mas tercharge We pay the shipping charges JIK 5 TOOLKIT 4 2252259 9t 65 00 P Cami ayyy inser a Mene FREE CATALOG 144 pages of hard to find precision tools Also contains 10 pages ofuseful Tool Tips i to aid in tool selection Send 4 for your free copy today JENSEN TOOLS amp alloys G90 SOUTH pRAET DIRAS TEMPE Az E28 CIRCLE NO 12 ON FREE INFORMATION CARD 114 HTC 88PF Foil pattern prototyping board with same layout as 88P to facilitate hard wiring of circuits de veloped on 88P breadboard sss 38 ICOM FLOPPY DISK INTERFACE For ICOM Frugal Floppy and FD3711 drives see Peripherals Altair bus computers Includes DOS software BASIC 50 extra Wired 300 IMSAI MEMORIES RAM 4A 4 4k static RAM memory Kit wired MN to ue m e 139 279 16k RAM Memory Kit wired 449 679 32k RAM Memory Kit wired 749 1099 65k RAM Memory Kit wired 2599 3899 PROM 4 512 4k EPROM board with 512 bytes of EPROM Kil Wired 1 tecum SESS 165 247 PROM 4 4 Same with 4k EPROM Kit wired TEUER CT
78. steel reference electrode drilled and solder plated pc board drilled and painted enclosure and l oz container of electrode gel kit PE 22 at 69 50 sepa rate drilled and solder plated pc board PE 23 at 5 95 set of two disposable Ag Ag Cl electrodes PE 25 at 3 98 pair of permanent Ag Ag Cl electrodes PE 26 at 19 95 l oz container of electrode gel PE 9 at 0 75 4 0z con tainer of electrode gel PE 9X at 2 50 Orders for complete kits shipped post paid and insured Orders for components and accessories shipped postpaid insur ance extra Add 1 00 for handling on orders less than 5 00 California resi dents please add 6 sales tax 644 for BART counties ELECTRONIC EXPERIMENTER S HANDBOOK MOTOR END PLATE VOLTAGE TIME MUSCLE FIBER MOTOR UNIT SINGLE FIRING MOTOR UNIT ANATOMIC MUSCLE ADDITIVE MOTOR UNITS FIRING THE SOURCE OF MUSCLE SIGNALS The signals picked up by the muscle monitor originate in large motor nerves each of which supplies pulses to any of 25 to 2000 motor end plates Only three end plates are shown in the diagram for simplicity Each set of end plates makes up a motor unit The motor units are not ciumped together but are interlaced to give the muscle its smoothness in movement The electri cal signal associated with the tensing of a muscle is made up of thousands of randomly additive microvolt pulses Each pulse is associated wit
79. that components must be carefully mounted so that their leads do not touch the ground though some com ponents and IC pins are soldered on the top side of the board to provide a ground These points are indicated in Fig 7 with an asterisk Since the board does not have plated through holes coincident pads A Q on both sides should be inter connected by small lengths of wire through the holes and soldered on both sides Use a clip on heat sink for integrated circuit C70 The LED s and switches are mount ed on the top cover as shown in the photograph All use 4 holes with grommets for the LED s Short lengths of insulated wire are used to connect the LED s and switches to the board Mount the LED s so that proper po sitioning and polarity are observed with LED6 at the center of the line LED2 toward player A end and LEDT10O atthe other end Green LED s are used for the WINNER and GO indicators while the others are red ELECTRONIC EXPERIMENTER S HANDBOOK THE SIMPLEST AM WWV RECEIVER ELIEVE it or not there really is a re ceiver small enough to fit into your ear At least the vital components active elements r f amplifiers detector and agc are small enough All of these components are in the ZN414 linear in tegrated circuit With the ZN414 and only eight out board components including battery and power switch you can make an AM BCB receiver that will perform at a level distinctly ou
80. that can be useful in some applications A triangle waveform is available at pin 9 with an output of 2 4 V and 0 5 linearity Be cause even light loading at the output will distort the triangle wave a high impedance buffer is recommended when using it Note that there is a short between pins 4 and 5 Pin 5 is the output of the vco while pin 4 is the input to the com parator In the SCA adapter these two pins are not used The output at pin 5 isasquare wave with an impedance of 5000 ohms and a level of 5 4 V p p As shown in Fig 5 pins 4 and 5 pro vide a convenient way to insert a pro grammable frequency divider for fre quency synthesis If the input Fern is a i l Lj 6 l Fig 5 Adding a divider permits frequency synthesis 10 kHz crystal controlled source and the divider is programmable from 1 to 10 the vco output Fa is 10 to 100 kHz in steps of 10 kHz all having the same stability as the crystal If a divider is programmed from 100 to 110 the vco becomes programmable from 1 MHz to 1 1 MHz in 10 kHz steps Unfortu nately the 565 can only operate to 1 MHz so this discussion serves only to ilustrate how you can use a phase locked loop and a programmable counter to synthesize almost any de sired frequency This in essence is how frequency synthesized CB and FM devices work If you have a synthesized local oscil lator you can receive almost any channel on any band prov
81. that permits the output to be isolated from the rest of the circuitry inside the IC So ifa 1 is placed at CE while the address is being changed the outputs will be at the logic 1 level The placement of this specific binary information into the ROM is called programming The means of programming is determined 21 QD 3 the decimal point To use up the entire storage Capability of the PROM the entire 00000 through 11111 series was used on the address lines A through A We will discuss later how to perform the actual programming procedure for the PROM An extension of the single character generator is the word generator Here we have several PROM s and an equal number of displays each programmed with identical information Depending on the number of PROM sand displays desired this system can be used to generate words strings of numbers identification and license numbers etc You simply set the address lines of each PROM to generate the character you want Model RR Track Patterns The PROM can also help an HO model railroader remember track patterns for his train layout As an example suppose an HO train layout has eight track switches and 10 possible track configurations A PROM can be used to re member the positions of the various switches for the 10 possible track patterns as shown in Fig B The outputs of the PROM would be connected to the track switches through electronic switches driver transistors This ensure
82. the beginner or hooked up through an FCC approved RF modulator In this latter approach the modulator is connected directly to the antenna terminals of a conventional TV receiver and the receiver tuned to a locally unused channel as is done with the very popular video games Since most computers come with only one O port and many hobbyists like to connect various devices to their comput ers the multi port plug in board was born These boards can contain up to a half a dozen I O ports each capable of INPUT DATA DATA BUS REGISTERS INSTRUCTIONS NM ADDRESSES ADDRESS BUS CONTROL SIGNALS TO BUS Fig 2 Logic diagramofa basic microprocessor supporting its own output device The vocal input which is the latest in peripherals that plug into a bus was de scribed in the May 1977 issue of POPU LAR ELECTRONICS and the reader is re ferred to that issue for all details Languages There are several ways to program a computer but as far as the computer is concerned there s just one way binary machine code Many com puters let you enter the necessary 8 digit strings of 1 s and O s directly others have conversion routines in their ROM monitors that let you enter the instruc tions as 2 digit or 3 digit numbers which is simpler Simpler still is to use assem bly language in which you enter the in structions in easily remembered mne monic abbreviations HLT means halt for exa
83. the sec ondary of the 6 3 volt 400 mA trans former to the two screw terminals at the right side of the 10 pad connector Strip Connect the primary of this transformer to the line power When the EIf Il is pow ered the two displays should indicate a random pair of hex digits Make sure that the three control switches RUN LOAD and P memory protect are all in their up off positions Placing the LOAD switch in its down locked position auto TT Lit tat ZAR ANG t X il LESS Ji 1 I s is i j e iU RN MAA aii l i l M LL i PROGRAM 1 Q LED TEST Memory Location Data 0000 7A 0001 F8 10 B1 0004 21 0005 91 0006 3A 04 0008 31 00 000A 7B 000B 30 01 matically causes the system to go to ad dress 0000 Release the LOAD switch and using the hex keypad touch the two keys as sociated with the first op code of Pro gram 1 This is 7A Then depress the INPUT key The data 7A will then ap pear on the two readouts In the same manner insert the remainder of Pro gram 1 into the system When the complete program is tn memory move the LOAD switch back to its upper position Then depress the RUN switch which will lock down You should observe that the single LED alongside the two 7 segment readouts will start to flash To test the graphics output connect the CRT monitor to the two connector Strip
84. thereby bringing about changes in general well being Relaxation is not achieved instan taneously and many training sessions may be required in difficult cases Since emotions play a large rolein the production of tension unexpected feelings may be experienced when one becomes familiar with letting go The simple EMG feedback monitor described here can be used to practice muscle relaxation and also to explore the building up of muscles A block diagram of the monitor is shown in Fig 1 The minute mi crovolts muscle signals detected by the skin electrodes are amplified and then applied to a rectifier integrator stage The pulses are averaged and either displayed on a meter or used to drive a voltage controlled oscillator that generates a series of clicks forthe audible signal The amount of muscu lar tension and the magnitude of the EDITOR S NOTE This muscle monitor is intended for experimentation and entertainment only It is not to be used as a substitute for professional clinical therapy Per Sons with heart disease high blood pressure or any other tension related illness should consult a physician The monitor isnot to be considered ahome sented for any illness 28 BUILD A MUSCLE FEEDBACK MONITOR New biofeedback technique helps to reduce tensions BY MITCHELL WAITE C EXP TEL E Wa de 3 T ki aA ANA ee amp ey ai E av a ES b DE av t A x 1 SD
85. to the lighted LED bank must be de pressed in order to ground voltage divid er R13 R14 and stop the sequence As an example assume S3 is in position 1 When S1 is momentarily depressed LED1 LED2 LED5 and LEDS will light in turn If S4 is depressed before C6 charges up to two thirds of the supply voltage the sequence will stop at LEDS which will remain lighted as long as S4 is closed Depressing S4 after LED8 is ex tinguished has no effect Depressing 54 after C4 is triggered and before C8 reaches two thirds of the supply voltage while LED8 is on LED8 will stay on and the junction of Q2 and H19 will be grounded Transistors Q1 and Q2 will now saturate causing point C to go to ground and point D to go to half of the supply voltage These two voltages are routed to the ring counter made up of IC5 through C9 The ring counter is ini tiated when power is applied but since the LED cathodes are at V they do not light When the voltages at points C and D are applied to the ring counter simul taneously the voltage at point D halts the counting Point C then grounds the cathodes of the LEDs causing the LED corresponding to the one timer in the high state to light The time constants associated with the ring counter stages produce the fol lowing probabilities of occurrence expressed as percentages sin gle 66 6796 double 13 3496 tri ple 3 34 home run 10 and dou ble play 6 67 The probabilities are ind
86. to 90 140 V 90 26A POWER SUPPLY KIT General purpose power supply with constant volt age transformer 9 V a 20 A 16 V a 6 A total Complete with key switch detachable power cord fuse holder Fully insulated plug together assembly mo I P ML M M n MM E ID 200 PERCOM CASSETTE TERMINAL INTERFACE Dual function interface board available in models for Altair and SWTP 6800 busses Cassette inter face is Kansas City standard with independent rec ord and playback circuits optional relay kit for pro grammed control of two recorder players Also in cludes RS 232 terminal interface Cl 812 For Altair bus Tape data transfer at 30 60 120 or 240 bytes sec RS 232 a 300 9600 baud KiU WIIBd es Cedo cgo cud A 90 120 Test cassette for above sees 5 CIS 30 For SWTP 6800 bus or any computer with 19 2 kHz clock UART USART or ACIA inter face Tape at 30 60 or 120 bytes sec RS 232 at 300 600 or 1200 baud Plays unmodified SWTP cassette software Kit wired 70 90 Remote Control Relay Kit eese 11 PICKLES amp TROUT TTVM 04 VIDEO MONITOR ADAPTER Kit adapts Hitachi and other TV sets using Hitachi SX chassis for use as 12 in video monitors Switch allows normal TV use Up to 90 char line BDPIO I O BOARD Eight port parallel O including two latched and six bus ports with uncommitted lines for power or user selected signals IEEE 488 HP IB bus adapter
87. two audio cassette recorders 150 MCEM K RAM 7k static memory 300 MCEM 4K RAM 4k Static memory 245 MCEM PROM PROG PROM programmer for use with 7K RAM Board 35 HAL Tiny BASIC in EPROM 250 HEATH H3 Computer with 8080A MPU 1k ROM monitor for load dums and front panel operations front panel with octal keypad and digital display With 10 slot IN WIRE WRAPPING Ol HAS THE LINE WIRE DISPENSER m 50FT ROLL OF 30 AWG KYNAR WIRE WRAPPING WIRE m CUTS THE WIRE TO LENGTH STRIPS 1 INCH OF INSULATION AVAILABLE IN FOUR COLORS WD 30 B WD 30 Y WD 30 W WD 30 R RED WIRE BLUE WIRE YELLOW WIRE WHITE WIRE 345 EACH PATENT PENDING 1978 Edition OK MACHINE amp TOOL CORPORATION 3455 Conner St Bronx N Y 10475 CIRCLE NO ON FREE INFORMATION CARO MINIMUM BILLING 25 00 ADD SHIPPING CHARGE 1 00 NEW YORK STATE RESIDENTS ADD APPLICABLE TAX KYNAR PENNWALT 212 994 6600 Telex 125091 101 cabinet using Heath 50 pin bus power supply capa ble of handling up to 32k of memory and two I O in terfaces programmable speaker and LED status lights Kit with wired and tested CPU BASIC as sembler editor and debug programs on audio cas ci tH Ee eT ere ae 375 8k RAM board with 4k ooo ee eeeec cece eeeeeeeee 140 4k RAM chip expansion Set cccceseeeeeeeree es 95 Serial l O board with 1200 baud audio cassette inter lace aaa Gaia ease 110 3 port paral
88. with flat black paint When the paint dries slip the two con ductors of the shielded cable up the tub ing and solder them to the leads of the LDR Slip the LDR with enough filler around it to hold it in place into the tub ing Solder a spade lug to the cable shield at each end and a phono plug to the insulated conductors at the end of the cable that goes to the control box At this point the entire system should be assembled minus R2 Tack solder a 10 megohm resistor across the lugs of J1 and a 10 000 ohm potentiometer across the points marked R2 on the PC board Set the pot to its midpoint Plug the line cord into an ac outlet and your enlarger lamp into SO2 Set H7 to its minimum resistance position turn on S1 and momentarily depress S2 Time out the cycle Then set H7 to its maximum resistance position depress S2 and time out the cycle If there is not a 2 1 ratio between this and the first position of R7 adjust the tacked in potentiome ter until you get this ratio Turn off the power unplug the line cord and enlarger lamp cord and unsol der the 10 meg resistor and pot do not disturb the latters setting Use an ohmmeter to measure the pots re sistance and select a fixed resistor of a value close to your reading for H7 sol dering it in the appropriate location on the PC board Then assemble the case The controller is now ready to use in your darkroom Making A Print It is now necessary only to determine the
89. 1 2200 ohm V watt resistor Misc IC socket 9 25 variable length spacers lens see text suitable chas sis Mounting hardware line cord etc R9 RIS8 IOK R32 R36 R37 R38 R39 R2 2 R30 R3 20K 20K DS IN5242 wi ok B 100N m us OtyF MS OF Y 2N3904 oF qaum OipF R42 R43 IOON i00 R45 R47 68K 5 6K i GND Z l IK R9 RI3 A R20 R29 20K R20 Re4 B R32 R39 R33 R34 R35 Note The following is available from CRO MEMCO 2400 Charleston Mountain View CA 94043 Image sensor C 1024 for 50 postpaid California residents please add sufficient sales tax R4 IK i Ci RSEN 5 seon x EXT CLOCK INPUT t ICi IMAGE SENSOR SV R5 IK acu I4 g 10 p Res c2 T Era IK Fig 2 Complete scheniatic of the camera Letters between sections ave merely for showing interconnections Letters in circles are terminals for use with optional cirexats 45v EJEXT CLOCK ENABLE 7 R6 IK R52 EXT 1 6 RESET Ic4 INPUT IC IC35 IC5 IC6 C7 7493 PIN 5 065 V PIN 10 GND ay ji Di INSI4 QI 2N3640 ms QVEM ICB 15K S R8 IK ol pF 5V 8V c5 ICIO pF MC7805 45V zn T COMPATIBLE OUTPUT C6 330pF Q2 D2 INSI4 ELECTRONIC EXPERIMENTER S HANDBOOK I ICI RI 7 Ics t SB 1 iv I R30 J amp 1 c pu d bus ec T5V LINE A IK B 20K C IOK Ice ca Fig 3 Actual si
90. 3 2N3055 Resistors All 2 watt 10 tolerance unless otherwise noted RI R3 1500 ohm R2 3900 ohm R4 RS R7 R9 1000 o0hm R6 22 000 ohm R10 100 ohm R 1 470 ohm RI2 1 megohm R13 0 3 ohm R14 Meter shunt see text R 1S 10 ohm wirewound potentiometer R 16 250 000 ohm carbon potentiometer R17 10 000 ohm 10 turn potentiometer S Spst switch Two of each required Fig 1 Low voltage supply of which there are tivo uses an IC regulator Automatic voltage and current limiting circuits activate the indicator lamp 11 tached to the rear panel to increase the surface area The current meters require shunts for 1 ampere operation R12 and R14 These shunts can be wound easily by hand using 28 enameled copper wire and a 1 watt carbon resistor any val VOLTMETERS LIMIT ADJ HIGH LOW HIGH LOW E p y i m wi zy k l iy y P Les i or Arrangement of component in Three electronic regulators are mounted on double sided circuit board prototype of triple power supply 15 ASA m 4 DI 3 3K PARTS LIST g m i Our F 5v R2 C1 C2 10 uF 20 volt electrolytic ca 5 3k pacitor C3 20 yF 50 volt electrolytic capacitor B HEP 3021 HEP7IO D1 15 volt zener diode HEPZ0225 HEP S9100 D2 6 volt zener diode HEPZ0214 Cr HH 1 28 volt 40 mA lamp Dialco 507 y 3917 1471 600 or similar J1 J2 S way connector red black OUN Q1 Trans
91. 3 d NSPTUVI Y T TEEN QUNM TET ew 4 VE art e M Sic io g mE Ww 9 a wv P C M Gi PM wer NER REPE Eu ANN 1 reet gi E pes E ES S iw t E d m ap b uh ds A r Mr ly 5 e A k ha WT noire UE voltage picked up by the electrodes varies the reading on the meter and the frequency of the clicking sound How It Works In a device of this type the differential input preamp lifier is the most important stage Q7 Q2 and C7 in Fig 2 This is because common mode signals such as Stray 60 Hz fields and associated line noises put a limit on the signal resolu tion The circuits common mode input impedance is compared to the source unbalance to determine the maximum common mode rejection ratio In the circuit op amp C1 is used as a bootstrap element The common mode signal on the collector of cur rent source Q3 is fed back to the input through R3 R4 and R5 so that the common mode signal actually sees an impedance much higher than the values of these resistors With this cir cuit the balance between C1 R1 and C2 R2 and the impedance of the elec trode determines the overall common mode rejection Making C7 and C2 larger in value improves common mode rejection but also in creases the recovery time due to trans ents at the electrodes Input noise in the circuitis minimized by using low noise transistors and designing the collector currents for low noise R f interference is drain
92. 35 28 23 1 2 2 25V 31 27 22 22135 28 23 17 3 3 25V 31 27 22 33 35V 28 23 17 4 725V 32 2B 23 47 35V 28 23 17 5 8 25V 36 H 25 58 35V 28 23 17 10 25V 40 35 29 1 0 35V 2B 23 7 15 25V 63 50 40 MINIATURE ALUMINUM ELECTROLYTIC CAPACITORS Axial Lead Radial Lead 47 50V 15 13 10 AT 25V 15 13 10 10 50V 16 14 11 4T 5QN 16 14 11 30 50v 15 13 10 1 05V 15 13 10 4M 16 14 12 1 0 25V 16 14 11 10 25V 15 13 10 1 50V 16 14 11 10 50V 16 14 12 A 716 15 13 10 22 25 17 15 12 4 7 25V 15 13 10 22 50V 24 20 18 4 7 50V 16 14 11 4729W 19 17 15 10 1 BY 14 12 g ATISUV 25 21 18 t0 25V 15 13 10 100 25V 24 20 18 10 50V 16 14 12 100 50V 35 3n 28 47 50V 24 21 19 220 25V 32 28 25 100 16v 19 15 14 220 50V 45 41 3B 100 25V 24 20 18 470 25V 33 29 27 100 50V 35 30 28 1000 16 55 50 45 220 16V 23 17 16 2200 16V 70 2 55 470 25V ELECTRONIC EXPERIMENTER S HANDBOOK POPULAR ELECTRONICS G SELEC EXPERIMENTER HANDBOOK SOLID STATE COMPONENTS CHART etico eee vuv ueeetereecas iviaeraedev remises eese lt ese esnoseavenstalsiends carvexerscishidtcsatesesoemintene BATTER UPE E erp FUE trea Ue bere Pes TIS EHE TUHBENE E EEIR A James J Barbarello A home electronic baseball game of Skill and quick reactions THREE WAT POWER SUPPLY 55 nai ned a A AAS UV ES E AE A A J R Laughlin HOW TO PROGRAM READ ONLY MEMORIES oeneeeesssosssasossssscccerssseseosonesecosaseccorssseresssesstoosesecee Robert D Pascoe Experimenter s guide to programmable ROM s EOW COSTP
93. 4 or 40 pin sockets oreet TREE E RE EIE EOS 25 JOLT Power Supply 5 12 10 V Supports JOLT MPU 4k RAM and O or MPU and eight I O cards Kit wired seeen rrna 99 145 JOLT 5 V Booster Option Fits onto JOLT power sup ply card supports MPU 16k bytes RAM or MPU 8k RAM eight I O or MPU 4k RAM and 16 VO eer 25 JOLT Tiny BASIC Resides in 2304 bytes of memory PROM version requires two 2k PROM cards nine PROMs Paper tape PROM 25 270 MINITERM ASSOCIATES SYSTEM 80 2 1 Z 80 based system with eight slot card cage and motherboard 16k dynamic RAM no wait 4 MHz 90 key keyboard 10 A power supply mini floppy interface for up to three drives one miniflop py drive software and firmware Wired 2699 MITS ALTAIR 8800b Second generation Altair 8800 New version com patible with Altair 8800 hardware and software Features inciude redesigned front panel new MPU board power supply and one slot motherboard ex pandable to 18 slots With crystal controlled clock pulse widths phasing frequency New front panel with multi color graphics longer and flat toggle switches Five new functions in front panel PROM Display Accumulator displays contents of ac cumulator Load Accumulator loads contents of eight data switches into accumulator Output Ac cumulator outputs contents of accumulator to VO 1978 Edition device addressed by upper eight address switches Input Accum
94. 8 X 67 10 or 53 6 kHz Since the band width of the SCA subcarrier is only 14 kHz there is more than enough lock ing range available This expression applies only when the input signal is high enough to saturate the com c5 c6 C7 OI8pFl O47yF OI8yF C4 OOl pF O OUTPUT R R8 R9 4 IK IK IK SEE TEXT Fig 3 Typical phase locked circuit for decoding SCA background music on FM broadcast calculate the value of C7 needed This works out to be 0 000895 or 0 001 pF Tuning resistor H7 is made up from a 1000 ohm fixed resistor in series with a 10 000 ohm potentiometer Remember that we assumed a value of 5000 ohms for R1 Using this larger potentiometer will enable tuning over a wide range around the center fre quency in case the tolerance of C1 is very broad while the 1000 ohm fixed resistor will act as a current limiter if the potentiometer resistance is re duced to zero PLL SPECIFICATIONS Type Min Input VCO Freq For Lock MHz 560 120 aV 15 561 120 pV T5 562 200 uV 15 565 1 my 05 567 20 mV 0 1 1978 Edition Lock Range V Min Max 1596 16 26 1596 16 26 1596 16 30 6096 10 26 12 4 10 parator If the input signal decreases the correction voltage also decreases thereby reducing the locking and cap ture ranges The curve in Fig 4 shows the lock ing range versus the input signal level Since the SCA decoder requires a 20 locking range the curve shows that a 10 mV input will be enough
95. As each ele ment is constructed it should be tested before final installation in the chassis ELECTRONIC EXPERIMENTER S HANDBOOK Author s practical embodiment of electromechanical light chopper shown in Fig 3 Calibration lamp is at left An r f transmitter triggers lamp HIS article will illustrate how photo cells are used in practical applica tions In some of the circuits described here we use an NSL 446 National Se miconductors Ltd 331 Cornelia St Plattsburgh NY 12901 Ithas a light to dark resistance ratio of about 1 1000 11 400 ohms in light to 12 000 000 ohms in darkness Maximum peak volt age is 420 V at peak power of 1 watt These specifications make it suitable for a wide range of sensing and control functions and are typical of many high power photoconductive cells A good way to experiment with photo cells without damaging them is to use al ligator clips for temporary connections Many cells with pin type leads are heat sensitive Thus both substrates and light sensitive materials can be dam SENSITIVITY CONTROL ISOLATION R2 TRANS SI IT VAC PHOTOCONDUCTIVE CELL EXPOSED TO OUTDOOR LIGHT Fig 1 Simplicity of application of photoconductive PCI POK EM NSL 466 FOR aged by frequent soldering To be on the safe side use a simple heat sink tool Miller No 80 for example or long nose pliers when soldering Daylight Operated Controller A basic applicat
96. But some ROMs are only semi per manent These include EROMs Eras able ROM or PROMs Programmable ROMs that can be programmed by the user you can get reasonably priced PROM programmers for home use then erased Once a bit pattern has been es tablished it will remain in the ROM even when the operating d c power is removed Individual RAM or ROM IC s come as so many bits by so many bits For ex ample 256 x 8 means that 256 bytes of data can be stored in that device These memory devices are usually used in blocks and mounted on a single PC board called a memory board You can purchase these as 4k actually bi nary 4096 8k 8192 16k 16 384 or as larger modules in either kit or wired form ROM boards are more expensive when you add in the cost of the ROMs they re usually extra and usually come in 1k 2k and 4k sizes i O Ports The Input Output ports are used to establish communication be tween the computer and the outside world As with memories there are several different types A serial port inputs or Outputs data one bit at a time digital In dian file because many devices the teletypewriter and some CRT terminals require serial data Special circuits with in the port convert the normally parallel data within the computer into serial form The speed of serial data movement is called baud rate expressed in bits per 84 second Because it is an electro mechanical device a teletypewrite
97. CARD 1 SN74D0N SN7AD1N SN7402N SN 403N SN7404N SN7405N SN7406N SN7407N SN7408N SN7408N SN7410N SN7411N SN7412N SN7413N 5N7414N SN7416N SN7417N 5N7420N SN7421N SN7422N 5N7423N SN7425N SN7426N SN7427N SN7429N SN7430N SN7432N SN7437N SN743BN SN7439N SN7440N SN7441N SN7442N SN7443N SN7444N SN7445N SN7446N SN7447N SN744BN SN7450N SN7451N SN7453N SN7454N CD4035 4LSO00 ALSO ALSO 4LSDA 4LS05 4LSUB ALS 4 513 ALSA 1 741520 TAL 826 74 527 T4L 28 74 830 74 832 r4LS40 74L551 741555 741573 MM5308 MM5311 MM5312 MM5314 MM5316 MM5318 16 16 21 16 18 24 20 29 25 25 18 30 33 45 70 35 33 21 33 48 37 29 29 37 42 26 31 27 27 25 15 89 59 75 78 75 8 69 79 26 27 27 20 cb4000 25 CD4001 25 CD4002 25 CD4006 2 40 CD4007 25 CD4008 58 CD4010 59 CD4011 25 CD4012 25 CD4013 AT CD4018 56 CD4017 135 CO4019 55 04020 1 49 CD4022 125 CD4023 25 CD4024 150 CD4025 35 CDA025 3 95 CD4027 69 CD4028 185 CD4028 2 90 CD4030 55 LM3U H B LM301H 35 LM301CN 35 LM302H 75 LM304H 100 LM305H 95 LM307CN 35 LM30BH 100 LM30BCN 3 00 LM309H 110 LM3 0S9K 99 LM310CN 2 95 LM311H 90 LM311N 90 LM317K 6 50 LM318CN 150 LM319N 130 LM320K 5 1 35 LM320K 52 135 M320K 12 135 LM320K 15 135 LM320T 5 175 LM320T 5 2 175 LM320T 8 175 LM320T 12 175 LM320T 15
98. COMPANDER sir ccrtecacrcsccoevie E A A A 10 DNE RR ERE TR REN CARIOR SPON DUI Craig Anderton BUILD A MUSCLE FEEDBACK MONITOR uu ccccccccccccsccccccscessecessseccececcesseusnenseceecessccceensesereeceseuess Mitcheil Waite New biofeedback technique helps to reduce tensions IC DIGITAL LOGIC MEMORY PROBE eerte eee enero Yo roe Pe EF Le eoe eC 1 ba Sep po PS ere ee reo Pap PE PeEe e UL os Ur sU see gere Eae Richard P May TWO PROJECTS ADD SAFETY TO NIGHT BIKING ALTERNATELY FLASHING TAILLIGHTS 1e cec eer ee nne eer oo ate a oo tate n o anna annoa aene etta ea aea nean So Terry A Williamson AEWAYS DNS BIKE LIGHTS zo iren er A A HEIN e a INS Charles R Clinkenbeard AUTOMATIC PHOTO ENLARGER CONTROLLER cene nsns sees kae ao sese sea sa sas ese aa s eee Joseph Giannelli Selects proper exposure time and cuts down on photo paper waste EOW COST METAL DETECTOR 5545 a a PL HERE NE RTR DEFENSE oases Ora Vida DIRE EE E ET EC IR Joe A Rolf BUIED THE MINIVOL TER oin LOI IINE EP POTE UI HIC E EUH ica Ide rri era nEoe A John F Hollabaugh AN IGNITION TIMING LIGHT FOR IMPROVING GAS ECONOMY eeeeeee eene enne eere nn nnn enses essa stas e sanno Anthony Caristi HOW PHASE LOCKED LOOPS WORK 1 noe sib re legebat Ped PERI eR a PeXa rka e cuna iva E EVER eU STUPET HR PORT VEREVS Herb Cohen Theory and applications of a circuit revitalized by IC technology g lcte n P luem E facies stents eae Ge swe races vised tanta ntb
99. DER Alphanumeric keyboard 63 keys with ASCII out put for parallel interface Includes repeat key latch outputs shift and shift lock extra control keys Can handle 833 char min repeat key rate 208 char in Requires 5 V d c 400 mA Project Board kit available as board only with instructions or as com plete kit less hardware case and power supply Board eR LE RENE 15 58 GEORGE RISK INDUSTRIES 753 KEYBOARD KIT Keyboard 53 keys with two key rollover upper case lockout three user definable keys Selectable parity data and strobe inversion Kit wired TT UTE IUBE Model 70 t Enclosule oe ooi CU bidon doe 15 RO CHE SYSTEMS MULTI CASSETTE CONTROLLER Controls four audio cassette recorders including write read and start stop through one interface Plugs directly into and is controlled through the Tar bell cassette interface optional mod kit for use with MITS Altair ACR See Module Boards for both In cludes operating system software with cassette se lection multiple files with update and merge split and duplicate two pass assembler record com pression and other useful Subroutine Optional soft ware text file editor I O drivers for cassette BASIC patches MBB 4B With four cassette ports Kit wired PER TS 125 175 MBB 2B With two ports es D95 135 MBB RA Two port add on sossssssessss 32 MBB MTS Altair Interface Mod s
100. E BUSINESS MACHINES INC 901 California Ave Palo Alto CA 94304 COMP SULTANTS INC P O Box 1016 Huntsville AL 35807 COMPUCOLOR CORP P O Box 569 Norcross GA 30091 COMPUTALKER CONSULTANTS P O Box 1951 Santa Monica CA 90406 COMPUTER CONVERSOR 1961 Old Middlefield Way Mountain View CA 94043 COMPUTER POWER amp LIGHT 12321 Ventura Boulevard Studio City CA 91604 C R C ENGINEERING P O Box 6263 Bellevue WA 98007 CROMEMCO INC 2432 Charleston Rd Mountain View CA 94043 CYBERNETIC MICRO SYSTEMS 2460 Embarcadero Way Palo Alto CA 04303 CYBERSYSTEMS INC 4306 Governors Drive West Huntsville AL 35805 DAJEN ELECTRONICS 7214 Springleaf Ct Citrus Heights CA 95610 DATAC ENGINEERING P O Box 406 Southampton PA 18960 DIGITAL GROUP THE P O Box 6528 Denver CO 80206 E amp L INSTRUMENTS 61 First St Derby CT 06418 ECD 196 Broadway Cambridge MA 02139 ECONOMY TERMINALS P O Box 12261 Minneapolis MN 55412 EDITYPER SYSTEMS 26 Just Road Fairfield NJ 07006 ELECTRONIC CONTROL TECHNOLOGY P O Box 6 Union NJ 07083 1978 Edition MANUFACTURERS ELECTRONIC PRODUCT ASSOCIATES INC 1157 Vega St San Diego CA 92110 ELECTRONIC TOOL CO 4736 W El Segundo Blvd Box 1315 Hawthorne CA 90250 EXPANDOR INC 612 Beatty Rd Monroeville PA 15146 EXTENSYS CORP 592 Weddell Drive Suite 3 Sunnyvale CA 94086 FORE THOUGHT PRODUCTS P O Box 386 C Coburg OR 97401 FRANKLIN E
101. E cefesee cd EN Ed US Les Solomon BUIEDCYGEOPRS Leche hune nU A Terry Walker Harry Garland amp Roger Melen First all solid state TV camera for experimenters BUILD A PERSONAL MICROCOMPUTER FOR 100 ieieeeeeseseseeeeese eese neenon t eese ten aaa asse adea ae nasa Martin Meyer Elf Il microcomputer trainer based on COSMAC 1802 microprocessor DIGITAL ELECTRONICS MICROCOMPUTER PRODUCT DIRECTORY MICROCOMPUTERS S 5 ones adest c T MT COVER PHOTO Conrad Studios ELECTRONIC EXPERIMENTER S HANDBOOK is published annually by Ziff Davis Publishing Company at One Park Avenue New York New York 10016 Herset B Sarbin President John R Emery Senior Vice President Finance and Treasurer Charles B Seton Secretary e COPYRIGHT 1977 BY ZIFF DAVIS PUBLISHING COMPANY ALL RIGHTS RESERVED e Material in this publication may not be reproduced in any form without permission Requests for permission should be directed to Jerry Schneider Rights amp Permissions Ziff Davis Publishing Co One Park Ave New York NY 10016 iE The Publisher has no knowledge of any proprietary rights which will be violated by the making or using of any items disclosed in this Handbook JOSEPH E MESICS Publisher e ARTHUR P SALSBERG Editorial Director e IVAN BERGER Senior Editor EDWARD BUXBAUM Art Director e PATRICIA GIRRIER BROWN Production Editor GARY GARCIA Assistant Editor ANDRE DUZANT Technical illustrator e JOSEPH E HALLORAN Adv Directo
102. H 989 MAN Common Ande reti 30 meg MAN 4740 Common Anode Red 400 9g MAN 7Y Counmicn Ande nei WO ru DL741 Common anode 600 150 MAN 5 Lninmon Anode green aig 99 Du Common Anndi B amp 0n s 5 MAN BS for mun Anode rer A 0 98 np ow Connan Gathi ti ADM 749 MAR 4 o onmp C mode ix t0 UL oak Cammin Cathode q 50 MAN B2 fummon Ange vellaw s 99 FND G fr nnen Calre 259 5 MAN B4 Uommnn Cathode yell ERU 99 FRIES Lu mp Cathare A 100 MAN 1820 ome un Ar mit rine wo 14 FNS Cannon Sande 00 1 00 FCS 8000A 3 Digt 8 Display HP 5082 7300 Series Multi Digit NEW 25 Pin version with colon amp am pm indicator e Ya ht e Common Cathode Red Mormon e Connecis a mosi one e 3 5 volts sa 5 miis second t i A for one with 3317 38174 j 2Digt 79 69 io om or D 13817 avaiabre at T segment Monolithic 3 Digit 89 79 RR 5 00 each Dip Package 4 Digit 99 89 FRONT VIEW FSCSO00 Typical segment Current 5Digt 1 19 99 SPECIAL BmA except colan 10 hrs ee eee ae ae NN s NN p amp cand rm 2 amp 4 TV GAME CHIP SET 14 95 4 95 EA which arg 16 m amp includes AY 3 8500 1 Chip and 2 010 mhz crystal 2 010 crystal 1 95 ea AY 3 8500 1 chip 13 95 e IC SOLOERTAIL LOW PROFILE TIN SOCKETS MAXIMUM FORWARD CURRENT 25 m s Forward voltage drop 1 5 volts
103. I O port accepts up to 4k RROMS VO E Eo MR UE 29 460Z MPU Expander Will accommodate Z 80 and a 6100 PDP 8 equiv MPU plus athird processor for multiprocessing under control of main 6502 MPU Also accommodates four PIAS for control plus sev eral multiplexers and demultiplexers Kit 125 4602 Subsystem Assembled 460Z plus eight slot ex pansion chassis and 4k 12 memory board 990 CPU Board Can support 6501 6502 6502A 6512 6800 6802 or 6802B MPUS up to two PROMs se rial video and Floppy PROMs available 1k RAM serial and parallel I O buffering for OSI System boards 400 Bare boards dta i a ui e I is 29 414A MPU board kit with 6502A MPU seriai PROM monitor serial port Kile ene meis 149 414V Same but with video PROM monitor no serial port requires 446 video board aarre 134 MODEL 500 Single board computer designed for stand alone use or as MPU module in larger system Accepts 8k ROM 4k RAM serial port 6502 MPU buffering for expansion Also available with power supply and case or in eight slot Challenger case with power supply Compatible with OSI Challenger and 400 Wired with 8k BASIC in ROM oo 298 PAIA 8700 COMPUTER CONTROLLER Single board computer 6503 MPU designed pri marily for control applications Includes hexadeci mal keypad connected by flat ribbon cable Re quires 5 V u 1 2A 12V 150 mA Kit 150 PARASITIC EQUINOX 100 8080A MPU computer
104. K S oos es 399 RAM board with 12K o5 rr oer tabe e teeter 575 HAM bo8ra WII T5 oe oe UT ere teeth 699 CMOS RAM Battery Module With battery backup to protect memory contents during power off Accommodates up to 2k bytes With 256 DUIBSS o pitas tet o oon LE 399 Wilbv 2k DYLES ae e REN DRE 899 ROM Module For up to 16k EPROM 2708 or ROM Steir se Ko Oo er PEE Ea ON CUP 82 EPROM Programmer Module with software on cas sette or paper tape oo ccc mm 199 Programmer software on 2708 EPROM 99 FANTOM II 1k ROM monitor ssesssses 29 Interfaces RS 232C For Contro Module serial port 39 Cassette Interface 300 and 2400 baud shares Con trol Module serial port with RS 232 139 Modem For data communications via telephone line includes touch tone dialing tones auto receive vun EPROM EUN ES ORE RT morc o cp 1499 Floppy Disk Interface for ICOM PERTEC 119 Analog Interface Less MUX ADC DAC 99 I6 channeb MUX G5 oer us coxa FircRe bu cnr AR 139 Eight bit DAC two max Each 59 Eight 10 or 12 bit ADC eoe onte arrra 149 Driver Sensor Module For external device control by relay and sensing Supplied less drivers and sen SOrS DUE With T6 DONS ono ire EROR EPI ARIES 69 Driver requires one port sssssssssssss 3 Sensor requires two ports ssssesssse 12 SYSTEM 68 Ca
105. LECTRIC CO 733 Lakefield Rd Westlake Vill CA 91361 GIMIX INC 1337 W 37th PI Chicago IL 60609 GNAT COMPUTERS 7895 Convoy Ct Unit 6 San Diego CA 92111 BILL GODBOUT ELECTRONICS P O Box 2355 Oakland Airport CA 94614 HAL COMMUNICATIONS P O Box 365 Urbana IL 61801 HEATH COMPANY Benton Harbor MI 49022 HEURISTICS INC 900 N San Antonio Rd Suite C1 Los Altos CA 94022 HOMESTEAD TECHNOLOGIES CORP 891 Briarcliff Rd NE Suite B11 Atlanta GA 30306 lIASIS INC 815 W Maude Ave Sunnyvale CA 94086 ICOM DIV PERTEC 6741 Variel Ave Canoga Park CA 91303 IMS Ai MANUFACTURING CO 14860 Wicks Boulevard San Leandro CA 94577 INFINITE INC 1924 Waverly Place Melbourne FL 32901 INTEL CORP 3065 Bowers Ave Santa Clara CA 95051 INTERNATIONAL DATA SYSTEMS 400 N Washington Suite 200 Falls Church VA 22046 INTERSIL INC 10900 N Tantau Ave Cupertino CA 95014 LEAR SIEQLER INC EID DATA PRODUCTS 714 N Brookhurst St Anaheim CA 92803 LOGIC DESIGN INC P O Box 3991 University Station Laramie WY 82071 M amp R ENTERPRISES P O Box 61011 Sunnyvale CA 94088 MARTIN RESEARCH 3336 Commercial Ave Northbrook IL 60062 MATROX ELECTRONIC SYSTEMS Box 56 Ahuntsic Stn Montreal Que Canada H3L 3N5 MICON INDUSTRIES 252 Oak St Oakland CA 94607 MICRO BUILDERS INK Box 28 D 1 Marineview Plaza Hoboken NJ 07030 MICRO COMPUTER DEVICES 564 S Greenwood Ave Montebello
106. M dual floppy disk drive cabinet DOE HEIC EO PTT See ee NS MERI SE eee Nr 5990 COMPUTER PERIPHERALS Fits Altair bus See Computers section for comput ers accepting this equipment directly Fits SWTP 6800 bus AXIOM EX 800P PRINTER 80 column line printer 160 characters per second Dot matrix on 5 in wide electrosensitive paper 96 character ASCII character set includes lower case Character size variable 5 20 characters inch under program control low paper detector bell case power supply Parallel interface 655 EX 800S Same with RS 232 serial interface larger ino Uer o b osten LO 740 PLOTTER All features of EX 800 plus graphic plotting capabil ity with 512 dots per line 16 rows per second Print head position feedback to computer 795 CENTER FOR STUDY OF FUTURE SELECTRIC PRINTER INTERFACE Drives IBM Selectric terminals with 24 V 30 msec pulse solenoids such as Dura 1021 and 1041 of fice Selectrics with Tycom Edityper adapters etc Can be modified for higher voltage solenoids In ciudes RS 232 input interface for seven bit ASCII conversion PROM no special software required hardware delay for carriage return tab and shift Requires 134 or 110 baud I O or CFSOTF SIO card Output only requires separate keyboard as input Select A Output interface card with conversion PROM solenoid drivers Requires 5 V 12 V and solenoid voltage 5 V 24 V or 36
107. M 25 49 5G 100 124 2 5 44 50 100 B pin iT lr 14 Aon amp id iR 14 pin w 14 tH Ier 28 pin 45 dd PET 1R pin fe EUN 20 3h mn nt 38 38 1B pan 28 rA A 10 tun hi 52 ft 2 Din n 3 SOLOERTAIL STANOARD TIN 14 pin Sur at M 2A pin amp og au LE B pin J5 n yi 10 puri ton 145 13 pr iq 4 42 SOLDERTAIL STANDARO GOLO R pn S 30 24 24 pin amp 0 63 5i 14 pin 4h dc 29 2B pin any 00 90 Hp 4 ag 2 ih nn 1475 t 40 26 1B ur 2 1 Vs 40 pin Ub 149 145 WIRE WRAP SOCKETS GOLO LEVEL 3 1D pin 4 5 jl D 24 pin 05 95 85 4 pin 9 4 a RR z H pun af 3 25 16 1h pin 43 4 di JF pu 154 t 45 an 18 pir Es bA h 40 pm 175 1 55 RESISTOR ASSORTMENTS 1 75 PER ASST 10 CHM UHM 15 OHM 18 OHM 2 OHM ASST 1 5 ea 2 OHM 3 DEM 38 DHM 47 HM 5h nM 1 4 WATT 5 50PCS 68 OHM R OHM 100 CHM 20 OHM 150 HM ASST 2 Sea B HM 220 OHM 2 HM 340 HAA Jun IHM 1 4 WATT 5 50 PCS 470 OHM SFO OHM nA OHM AAN HM 1h ASST 3 Sea RR EL 2k HL 1 4 WATT 5 50 PCS 3 d 3 gk 17h 5 Ah h AR ASST 4 Sea Aah 10k E IO 1B 1 4 WATT 5 50 PCS Fra iR 13k 30k ATE ASST 5 5 ea Sbk Bfr Ags 10r 170k 1 4 WATT 5 SO PCS 150r POF 2208 270k 330 ASST 6 Sea wr 347 ZAQ BANK 420v 1 4 WATT 5 50 PCS 1M DM 5M 18M 2 M ASST 7 Sea 77M aM 3 9M 1 M 5 6M 1 4 WATT 5 4 SOPCS ASST BR Includes Resistor Assortments 1 7 350 PCS 10 95 ea 5 00 Minimum Order U S Funds Only Spec Sheets 25e Se
108. MT EMITTING RECTIFIER DIODES AND ASSEMBLIES SYMBOL CASE LOw POWER 2 3 4 MEDIUM POWER 4 5 6 HIGH POWERS r 6 LASER 7 ASSEMBLIES p LOW MEDIUM POWER pa E MEDIUM HIGH VARACTOR riiui POWER KR a ie a je E E 5 OPERATIONAL AMPLIFIER OP AMP 2 BUFFER INVERTER COMPARATOR INPUTS 4 JU rt IX 5 ek 3 6 OR GATE AND GATE if 0 JL BA mn 3 4 BCO TO DECIMAL DECODER NOR GATE NAND GATE I Sm J Fu CLOCK C E XCLUSIVE OR K RQ INPUTS XOR GATE hl RESET DUAL IN LINE PACKAGES DIP S MINI DIP 14 PIN DIP amp CLOCKS CALCULATORS COMPUTERS ETC USE ICS WITH UP TO 66 PINS ON A SINGLE DIP JK FLIP FLOP Q 4 00 wc Pb od nm i i6 BCO TO SEGMENT DECODER 15 14 13 2 u 10 9 16 PIN DIP 7 SEGMENT DISPLAY OU it INVERTERS GATES FLIP FLOPS DECODERS ETC 1978 Edition BASIC in ROM Computers by Ohio Scientific If you re just getting into personal computing and are buy ing your first machine you re probably confused by the myriad of companies and products available However there is one simple guideline you should follow when choosing your first computer Be sure that it is capable of giving you full floating point BASIC the instant you turn it on Machines with full 8K BASIC in ROM cost as little as 298 00 Why should you settle for anything less Challenger IP The Challenger HP from Ohio Scie
109. O and another for each 1 to allow inexpensive audio recorders to store di gital data The playback system con verts these tones back into O s and 1 s toload the data back into the com puter Incidentally a modem short for modulator demodulator used for digi tal communications over telephone lines works much the same way Unfortunately there are many stand ards governing the choice of frequen cies and data transmission rate such as the Kansas City standard Tarbell stand Fig 1 Five elements of a basic computer are interconnected by a bus structure MEMORY TO joUTSIDE WORLD FROM D CLOCK CONTROL DATA ADDRESS VOLTAGES SIGNALS LINES LINES BUS ELECTRONIC EXPERIMENTER S HANDBOOK ard and several used only by one com pany apiece such as MIT s ACR and Processor Technology s CUTS Re cordings made on one system will be meaningless to a computer set up for another you must always make sure that any recordings you get are compat ible with the system you have Video display modules are used when you want to see your computer s output on a TV like CHT screen without going to the expense of a complete terminal see Peripherals The screen can be long to a CRT monitor like a TV set without a tuner specifically designed for computer or closed circuit TV use or it can be part of a conventional TV set either converted for direct video input not recommended for
110. PERIMENTER S HANOBOOK picture camera lens with variable stops for this project Both new and used movie camera lensesare available from photography stores and mail order houses A 12 5 mm f 27 lens is available from Edmund Scientific 300 Edscorp Bldg Barrington NJ 08007 for less than 10 stock No 41 146 m qeu hum po m j r EY riw Bx L Pac Bl ug Eje pg ye te Wal da Fase 2 i Setup and Operation Connect e a as DE AL E Cyclops to an oscilloscope set to ex EM MA ternal horizontal as follows J1 to horizontal input J2 to vertical input J3 to ground and J4 to intensity input If your scope does not have provision for anintensityinput modifyit accord Ing to Fig 5 With power applied to both Cyclops and the scope adjust the scope s horizontal and vertical gain until a 32 by 32 pattern of dots forms a WW square array on the screen Cover the lens of Cyclops and then turn the scope s intensity control down until the dots just disappear Now expose thelenstoalamp Thedots on the CHT will illuminate To adjust the focus between the image sensor and lens turn the bias lamps down H1 at maximum resis tance and expose the lens to a simple illuminated test pattern such as a black cross on a white background If the lens can be focussed adjust it for the distance between the lens and the test pattern Set the lens to its widest m s i 2 a a a ee o T ae P au e y
111. PROM Programmer For use with P 38l or FF 1 25 SOLID STATE MUSIC MEMORIES MB4 4k 8k memory board can be converted from 4k to 8k by piggy backing memory C s and changing Switch and jumper settings es Deas ataca ctas ws 130 5180 8k se 210 300 MB6A 8k memory board Switch selected memory protect address assignments and wait cycles Pro vision for battery back up Kit wired 265 325 MB7 16k static memory Switch at top of board al lows address selection to any 4k boundary without removing board memory protect separated into 4k biockscKit wind ooa uat i 525 625 WIRE WRAPPING TOOL For AWG 30 025 0 63mm sq post MODIFIED wrap positive indexing anti overwrapping device PROM MEMORIES MB 3 2K 4K Switch selectable address and wait cy cles Kit only Less EPROMs with eight 1702 EPROMs 2k with 4k 65 105 145 MBS 8k 16k Similar to MB 3 but uses 2708 EPROMS Kit only less EPROMS 5 85 INTERFACES 10 2 Input Output PROM and universal Board One parallel I O port committed with provision for three additional ports including one serial provisions to facilitate wiring for EPROMs etc Board kit wired 30 55 80 TARBELL 1001 CASSETTE INTERFACE Saves and reads data on audio cassette machines Data transfer rates up to 540 bytes per second with high quality cassette recorder 187 bytes sec sug gested for medium
112. PU with ROM 1k RAM room for addi tional 1k ROM 425 1501 Video interface 16 64 characters 385 1503 Alphanumeric keyboard 125 GNAT GNAT PAC Wisi xtlma EALER tax t 5o Ania 8080 MPU system available with built in mass stor age Basc system includes MPU with eight vec tared interrupts 16k RAM module expandable to 64k 1k PROM monitor expardabie to 16k siots for four additional module boards cabinet and pow er supply G Gnat Pac base unit Wired 1750 SYS 7 Same with 3M data cassette drive 1k PROM with drivers tape operating system wth assembler editor on 3M data cassette 2795 SYS 8 Same with Minifloppy disk drive instead of cassette drive DOS with file manager etc on dis kette disk based BASIC compiler available 2895 8005 Hardware multiply divide module 225 8631 I O module one serial two parallel 225 8035 Foui port serial I O 300 CA 1 Cable one required for each serial port 15 8090 92 Front panel display and contro 350 HAL EIGHT THOUSAND Compact 8080 MPU computer with 1k ROM moni tcr up to 16k RAM externally expandable to 64k one seria port RS 232 or 20 mA ASCII or Baudot video output 16 lines 64 characters power sup p y and cabinet With 2k 9k 16k 1195 1425 1650 MCEM 8080 Single board version with 1k ROM ronitor ports RAM only 375 MCEM DACI Dua audio cassette interface Kansas City standard 300 or 600 baud 1200 baud selecta bie for
113. QUERQUE NM 87410 3120 San Mateo N E 505 883 8282 883 8283 ALBANY NY 12244 269 Osborne Road 518 459 6140 NEW YORK NY 10018 55 West 39th Street 212 221 1404 DALLAS TX 75234 3208 Beltline Road Sulte 206 214 241 4088 Metro 263 7638 HOUSTON TX 77036 7302 Harwin Drive Sulte 206 713 780 8981 RICHMOND VA 23230 4503 West Broad St 804 355 5773 SPRINGFIELD VA 22150 6605A Backlick Road 703 569 1110 CHARLESTON W VA 25304 Municipal Parking Bullding Sulte 5 304 345 1360 120 DIRECTORY OF MANUFACTURERS Continued from page 119 PROKOTRONICS 439 Marsh St San Luis Obispo CA 93401 QUAY CORP P O Box 386 Freehold NJ 07728 RADIO SHACK 2617 W 7th St Fort Worth TX 76107 RCA SOLID STATE DIV Route 202 Somerville NJ 08876 GEORGE RISK INDUSTRIES G R I Plaza Kimball NB 69145 RIVERSIDE ELECTRONIC DESIQN 1700 Niagara St Buffaio NY 14207 RMQ SYSTEMS COMPUTER KITS INC 1044 University Ave Berkeley CA 94710 RO CHE SYSTEMS 7107 Mammoth Ave Van Nuys CA 91405 SCOPE DATA INC 3728 Silver Star Rd Orlando FL 32808 SEALS ELECTRONICS P O Box 11651 Knoxville TN 37919 SHARP amp ASSOCIATES Box 26045 Lakewood CO 80226 SMOKE SIGNAL BROADCASTING Box 2017 Hollywood CA 90028 SOLID STATE MUSIC CYBERCOM 2102A Waish Ave Santa Ciara CA 95050 SOROC TECHNOLOGY 3074 E Miraloma Ave Anaheim CA 92806 SOUTHWEST TECHNICAL PRODUCTS SWTP 219 W Rhapsod
114. RI e e C2 9 e R2 9 1 amp GND e SPKR och I C 1 7 e C6 2 C4 zu e R5 e e R4 9 Fig 6 Etching and drilling and parts placement guides for Sound Option Inter unit wiring is best done with a 3 foot length of flat cable 12 conductor is satisfactory This cable is extremely flexible and will not interfere with play A 7 conductor piece and a 4 conductor piece are also required both can be ob tained from the 12 conductor piece The Batters Box includes switches S4 S5 and S6 Calculator switches have been chosen as they seem to be best for most people s reactions A rec tangular cutout 4 x 15 16 1 3 x 2 4 cm is made in the top plate The switches mount on the pc board as shown in Fig 4 This arrangement holds them in place The cable enters the case through a hole drilled on one of the short sides and the four leads are soldered to the undrilled pads Once wired the pc board can be secured to the top plate with tape or a few dabs of epoxy The case is 4 x 244 x 244 10 2x5 7x57 cm Lettering is the same as for the playing field The Pitcher s Mound uses a 12 posi tion 3 section single pole rotary switch and is wired as shown in Fig 5 Again the cable enters the 5 1 16 x 2 x 1 12 9 x 6 7 x 4 1 cm case through a hole drilled in one of the short sides Sound Option If you plan to add the sound option mount a miniature
115. RS C36D 15A 400V SCR 1 95 C38M 35A 200v SCR 195 2N2328 1 6A 200v SCA 50 MDA 980 1 12A 50V FW BRIDGE REC 195 MDA 980 3 12A 200V FW BRIDGE REC MPS ADS 55100 TRANSISTORS a d bip m Do PN3567 3 100 74400 a 100 282221 15100 PNA3S6B agi og 2Naa01 a 00 2N2227A 5ST OL PN3569 1 00 284402 1 100 2N2350 5 100 ge 2N3714 5 1 00 poen 41 00 2ND359A AS 00 2N3705 55100 Lo 2nasog 55100 2N2484 451 00 23706 55100 2N5086 451 00 2N2006A 4 1 00 2N3707 8 100 o 2N ano 7M2007A 541600 ang 58 00 N5088 4 100 N2925 4 1 00 ENT 5 B5 285089 18100 28053 P5100 N i725 100 war ag 5100 2N3055 B6 2N1903 5 100 7N 138 ssim MJE3055 1 00 2N3904 i 0 285138 5 1 00 MJEZ955 15 2N3305 un 25209 5 100 2NV2 53100 23906 asta J N5gs 5 100 23198 5 1 00 PNAD 4 18100 CHOBBISCR 231 00 P OQ 3 100 2N5432 2 00 2NA123 10 51 00 CAPACITOR so voir ceramic CORNER DISC CAPACITORS 1 4 10 49 50 100 19 10 49 50 100 10 pf 05 04 03 OCipF 05 pa 035 22 p n5 D4 03 0047 uF 05 04 035 47 pf 05 04 03 MaF 05 4 035 100 pt 05 ga 03 U224F 06 05 pa 220 p 05 04 03 47 uF 06 05 04 470 p 5 O4 nas VF 12 09 075 100 VOLT MYLAR FILM CAPACITORS OO 1mf 12 10 07 D22m 13 11 08 0022 12 10 07 047 mt 21 7 13 0047mt 12 10 n 1mf 27 23 17 Dimi 12 10 07 22m 33 27 22 20 DIPPED TANTALUMS SOLID CAPACITORS 1 35V 28 23 17 1 5 35V 30 26 21 15
116. Senior Vice President Frank Pomerantz Vice President Creative Services Arthur W Butzow Vice President Production Lawrence Sporn Vice President Circulation George Morissey Vice President Sydney H Rogers Vice President Sidney Holtz Vice President Albert S Traina Vice President Paul H Chook Vice President Market Planning Edgar W Hopper Vice President Robert N Bavier Jr Vice President Charles B Seton Secretary Jerry Schneider Vice President amp Administrative Director Annuals William Ziff Chairman W Bradford Briggs Vice Chairman Zitf Davis Publishing Company Editorial and Executive Offices One Park Avenue New York New York 10016 212 725 3500 Midwestern Office The Pattis Group 4761 West Touhy Ave Lincolnwood Illinois 60646 312 679 1100 Gerald E Wolf Thomas Hockney Michael Neri Western Office 9025 Wilshire Boulevard Beverty Hills Cal 90211 213 273 8050 BRadshaw 2 1161 Westem Advertising Manager Bud Dean Japan James Yagi Oji Palace Aoyama 6 Chome Minato Ku Tok yo 407 1930 6821 582 2851 refer to any issue at any time Both decorative and attractive enough to enhance the decor of any room each case holds a full year s copies Constructed of reinforced fiberboard these durable cases are covered in a rich textured leatherette The gold embossed back adds to its elegance and makes each case a welcome addition to your bookshelf or cabinet Cases are ava
117. T MAKES PRINTED CIRCUITS THREE WAYS 1 FULL SCALE ARTWORK MASTER MAGAZINE ART ILLUSTRATION FILM DEVELOPED PHOTO RESIST ETCHED Positive ab NEGATIVE e IMAGE ON a CIRCUIT COPPER CLAD BOARD CIRCUIT BOARD 3 DIRECT ETCH DRY TRANSFERS APPLIED TO COPPER CLAD BOARD The revolutionary photographic way that makes PERFECT printed circuits from YOUR ARTWORK ora PRINTED PAGE No camera No darkroom No tracing No film cutting Simple and fast KIT CONTAINS 5 x 6 steet printing frame 4 sheets s x b photocopy film yellow filter chemicals for pint tim developer and pint film fixer 5 x 6 copper clad board 3 x 4 x Il layout film l pint resist developer 2 sheets 8l roll 1 16 printed Opper clad board spray can of photo etch resist circuit tape roth 32 printed circuit tape amp sheets dry transfer direct eti h PC patterns including pads transistors round can and flat pack ICs DIP ICs edge Card connectors tines circles jogs etr alh anhydrous ferric chloride to make pint etchant instructions ER 4 COMPLETE PHOTO ETCH SET MEET N J residents add sales tax i m postpaid 26 95 AT YOUR DISTRIBUTOR OR DIRECT the DATAK corp 65 71st Street Guttenberg New Jersey 07093 CIRCLE NO 8 ON FREE INFORMATION CARD 113 FRANKLIN ELECTRIC 8k RAM 8k static RAM board Kit wired 225 280 With IC sockets add 2 00 0 cere cee eee m 15 GIMIX GHOST VIDEO BOARD Disp
118. T Double density IBM 3740 type hard sector disk 300k bytes controller for RS 232 ASCII interface has power supply enclosure built in DOS Trans fers at 19 200 baud erre 795 SMOKE SIGNAL BROADCASTING BASIC FLOPPY DISK SYSTEM Mini Floppy system with disk controller plug com patible with SWTP 6800 cabinet power supply and controller handle up to three Shugart Mini Flop py drives May be purchased compiete or addition al drives can be added later Includes DOS software in PROM Stores 80k bytes per disc BFO 68 With one drive sese 795 BFD 68 2 Dual drive eee enn 1169 BFD 68 3 Triple drive sssssssesuuusss 1539 Additional drive for 68 or 68 2 390 SOROC TECHNOLOGY 1Q 120 TERMINAL Displays 12 lines 24 optional 80 char line on built in 12 in CRT Includes keyboard with cursor control numeric keypad tab auto repeat ASCII 64 character uppercase set upper lowercase 95 character set optional RS 232 interfaces to computer and extension port optional for printer etc Has protect mode displays protected data in reduced intensity Can erase to end of line end of field end of memory all unprotected data or com plete screen Switch selectable baud rates 75 19 200 Kit wired 5 995 1495 SOUTHWEST TECH PRODUCTS CT 64 TERMINAL CRT terminal 16 lines of 32 or 64 characters per line s
119. V plus indicator lights and switches Kit wired 325 395 Select B Same with 5 V and 12 V supplies on card plus externally mounting transformer Kit WIRE err ti ete EIE T 375 455 Seiect C Same as B with 24 V solenoid supply Kip ipd cu eee ee eee 395 495 COMPUTER CONVERSOR CONVERSOR 8000 VIDEO TERMINAL Video terminal 24 line available for 40 or 80 cha racter lines with and without built in acoustic cou pler ASCII uppercase 64 character set RS 232 in terface 110 300 baud automatic wrap around and scrolling Wired 400 40 character ee etr o ce tete 595 401 Same with COUD er seeders 705 BoD SO charactet ede eot ce EE LL 695 801 Same with coupler sesssse 805 900 80 character CONVERSOR in 12 in monitor loss keyboard 2 2450 ee rere ibas brass 750 9000 As above but with keyboard assembly and ca ble oae MO NETS tei c ST Oa 825 Tape recorder connections for 401 801 for offline SIG dOB store ctia E seamen 30 MODEL 100 KEYBOARD Uppercase ASCII 53 keys in case 129 ELECTRONIC EXPERIMENTER S HANDBOOK MODEL 200 MONITOR TV 12 in CRT modified for 80 character line 175 Model 300 Acoustic Coupler In case 175 CROMEMCO JOYSTICK CONSOLE Joystick 2 axis with speaker and amplifier plus four user defined pushbutton switches Joysticks a Dr w e at e miter d 2 V each axis spring return to center Fo
120. a hobby In a series of unique experiments doctors have used the still good EMG signals going to an amputee s missing limb to control a Morse code relay Patients have after brief training learned to send up to 15 words per minute By using a rectified EMG signal 360 degree servo control for an antenna and tuning coils was achieved Learning to Control Tension Headaches Experiments have shown that by monitoring the frontalis or forehead muscle and using feedback people can learn to reduce the occur rence of tension headaches When presented this information in a com fortable manner patients have learned to abort the headaches without the biofeedback equipment Lowering Anxiety EMG biofeedback has perhaps its greatest potential as an aid to anxiety reduction By helping psychologists show their patients how to initiate self induced calm and real relaxation EMG monitors would be useful Though still in its infancy this application has vast potential and is the area of most interestfor EMG at this time parent Thefrequency range ofthe vco IS approximately 5 to 30 pps Power for the circuit is provided by two 9 volt batteries The power for the input stage is decoupled by R20 and C12 for the positive side and R27 and C13 for the negative Construction Due to the high gain and complexity of the circuit a pc board should be used An actual size foil pattern and component placement are shown in Fig 3 When installin
121. a short duration pulse that would otherwise not be seen on the 1 and O LED read outs To expand the stretching feature a switch on the probe can be used to activate a memory mode that causes the stretch LED to remain on perma nently after a positive or negative pulse occurs The memory mode can aid in establishing the presence of 32 BY RICHARD P MAY unwanted pulses such as noise To reset the memory the switch is simply returned to the stretch mode The memory mode can also be used to detect a power failure that might cause a sequence scrambling in the system under test To accomplish this the power input leads of the probe are connected to the 5 volt supply line and the switch is set to the memory mode If the power should fail and self restore it will leave the stretch LED illuminated indicating that a power in terruption has occurred Construction To keep the project as compact as possible so that its simple circuit see Fig 1 will fit into the pen light body printed circuit construc tion is highly recommended An actual size etching and drilling guide is shown in Fig 2 Also shown are two component placement guides since the component mount on both sides of the board Before you begin assembly remove from C7 7404 pins 5 6 8 9 12 and 13 and from C2 9601 pins 5 8 9 10 and 12 This will permit maximum utilization of the available board space Then mount and solder in place all co
122. acitor DI through D4 1N4001 DS through DIO IN4148 1978 Edition DIS1 NSN 373 dual 7 segment display Na tional Q1 Red light emitting diode R1l optional dropping resistor tf Tl output greater than 6 3 volts at 400 mA The following resistors are V watt R2 R31 R32 470 ohm R3 R27 R28 390 ohm R4 through R17 1 20 ohm R 18 not used R19 through R26 R29 47 000 ohm S1 S5 through S20 spst momentary keypad switch 2 S3 S4 spst latching keypad switch TI transformer 6 3 volts 400 mA XTAL 3 58 MHz color TV crystal Misc 86 pin bus connectors optional 10 screw terminal strip mounting rails and hardware line cord sockets for all IC s Note A complete kit for the EIf 1I except for T1 including double sided pe board with plated through holes is available from Net tronics Ltd 333 Litchfield Rd New Mil ford CT 06776 for 99 50 plus 3 00 post age and handling COSMAC 1802 Users Manual 5 50 It 5V zofief iof el NR mc 19 S 3 poscere Ic ss RAM NETT EU MEM TO KEYBOARD 108 Ai Icio A jej i3 pe u ICIO 4023 ICIO Icio A2 B C IC3 934 2101 5V ioY a3 RAM 3 gt ICI A7 PIN14 i3 11 9 i4l i2 10 DATA BUS INPUT SWITCHES SHOWN IN DOWN OR OFF POSITION Power Supply Elf I s power supply uses an on board bridge rectifier and fil ter that drives the 5 volt regulator C A18 This permits the use of a conv
123. acks for Data Handler and expansion board ssssss 19 Dust Cover Hinged plexiglass dust cover with cut out for switch and keypad access 14 Expansion Board Includes 12k RAM 1k EPROM with O routines etc 80 character 25 line video interface with upper and lowercase Greek and some graphics characters interface for mini floppy CSI rie nee er re ee 350 WINTEK WINCE MICRO MODULES 6800 MPU modular system consisting of the fol lowing Wince Control Module 6800 MPU board with 128 bytes RAM one Serial or parallel port space for up to 512 bytes RAM one serial and two parallel ports Minimum configuration 128 Bytes one POM Loo oe aE aeea aE 149 Maximum configuration 512 bytes three ports EME ERAN A See MN Nah rer E on MEE OE PEE 199 Back Planes FOUR SOCK ON pete area re eae ee 50 EIGMESOCKE sarc terete eee 90 Power Supplies BN ung Ae Se V0 DOO MIR eerren tentera 85 Sa ie S AE a a Cae O Rana A e one ee a 170 Console Module Keyboard and digital displays provision for up to 25 key switches up to 16 display digits Optional real time clock provides interrupts Less keys displays clock oet 139 For real time clock BOG een 29 For each display digit add ss 10 FOr ach key switch add eere 8 Dynamic RAM Memories RAM refresh module sssssssseen 99 HAM board With 4K covers restet eer eens reEERR 275 HAM board wit B
124. agement with named binary and symbolic files IBM compatible floppy disk format Altair bus interface has boot strap in ROM Wired only 600 Model 200 Dual drive eere reete 875 MICROCOMPUTER ASSOCIATES VIDEO TERMINAL VT 100 Keyboard terminal for connection to TV set Uses RS 232 or 20 mA interface Typewriter style key board with upper and lowercase ASCII control functions rotary baud rate switch to 9600 baud two key rollover Displays 32 character 16 line page two page memory supplied 1k expandable to 16 pages Data can be edited on screen before transfer to computer Cursor controllable 595 MIDWEST SCIENTIFIC INSTRUMENTS FD 8 FLOPPY DISK 300k bytes per disk Single drive system interfaces to any parallel port parallel interface card available for SWTP6800 Read after write for error check Complete disk operating system available for 6800 based systems disk driver and Mini DOS routines may be integrated with BASIC for 8080 systems In cludes controller for up to four drives Kit wired ETE SD Me Rer apta ap Geant ear Br e nas 1150 1395 Dual Drive System Kit wired 1950 2295 MINI DOS system on PROM 1702 250 FDOS BASIC On diskette sseesssssssss 65 FDOS Bootstrap Only 1702 PROM 125 Additional drives essere e 900 PIA 1 Parallel interface card for SWTP 6800 com pute
125. al battery backup power does not load CPU except when clock is set or read Time is set and read via I O instructions port addresses selectable timed interrupts under software control Draws 400 mA BV 88 SPM Clock module Kit eee 96 88 SPM 50 50 Hz version eseeeemm eee 96 88 ICS IC sockets for above aisen 10 88 XTAL Crystal timebase for 8B SPM 25 88 SPM A Assembled with sockets and xtal 199 UNIVERSAL FREQUENCY COUNTER Frequency and interval counter nine decades soft ware controlled making programming and reading possible for process control applications Measures frequency from d c to 500 MHz and higher Soft ware selection of interval and timebase port one of four counter period interrupt enable for time period stop run counter Kit wired 149 199 88 MODEM For telephone data communications Originate mode with auto dial feature allows your computer to call others answer mode allows others or termi nals to call yours Compatible with Bell 103 data sets at rates from 110 300 baud including 133 4 Selectric speed 0 600 baud when communicating with other 88 MODEM modules Kit wired Met anam TER MATROX VIDEO RAMS Video controller modules addressed as RAM mem ory each on screen character equivalent to a one byte memory location Character blinking available Controllers available as plastic packaged modules or as co
126. amily of Anir zer ipha ral equipmen including floppy disk line x printer audio e cassette record R interface A D converter PROM program mer serial and parallel I O boar s iar NOTE Altair is a trademark of MITS Inc t FTIT ETITI c Foice of fou d fferent memory boards and many others Reli abiity The unique design feacures of the Altair 8800b which have set the stardard for the microcomputer industry make if the most reliable unit of ite kind The Altair 400 pin bus the now standara design used by many imi tators has been standard all wong at MITS The unique frort Panel hterface Board on the Altair 8800b bolates and filte s front panel noise before t can be transmitted to the bus The all new CPU board utilizes the 8080A microprocessor Intel 8224 clock generator ard 8246 bus drivers Flex abili ty Meeting the diversified cemancs of an ever increasing microprocessor ma ket requires flexibility not just hardware fexibility but ah Th 7X 3 E Ld mE culo pua l ET Ope ii ni pg D dob m dum EATA E 15 E Ard X a f CIRCLE NO t4 ON FREE INFORMATION CARD software flexibility as well MITS software including the innovative Altair BAS C tan guage allows the full prential of tha Atoir 8800b computer to be real zed 8x AUAIR BASIC has fccilities for variable length strings with LEFTS RIGHTS and MIDS functiors a concatenc
127. and fully teatured so there s no need to purchase bits and pieces from different manu facturers We have everything you need but almost any other equipment can be easily supported too thanks to the uni versal nature of our systems Our systems are specifically designed to be easy to use With our combination of TV keyboard and cassette recorder you have a system that is quick quiet and inexpensive To get going merely power on load cassette and go Une Clg miel Group P O Box 6528 Denver Colorado 80206 303 777 7133 OK I d like to get to know you guys better Send me the whole package City State Zip LL LL LL Design shortcuts have been avoided all CPUs run at full maximum rated speed All system components are available with our beautiful new custom cabinets And every new product will maintain the same unmistakable Digital Group image The Features Digital Group Systems CPUs currently being delivered Z 80 by Zilog 8080A 9080A 6800 6500 by MOS Technology All are completely interchangeable at the CPU card level Standard features with all systems Video based operating system Video Cassette Interface Card 512 character upper amp lower case video interface 1024 optional 100 character second digitally synthesized audio cassette interface CPU Card 2K RAM Direct Memory Access DMA Vectored Interrupts up to 128 256 byte 1702A boo
128. and income No cross town commutes You decide when and where you study best Your eventual success at CIE and in your elec tronics career will be determined by your own motivation and self discipline You can do it And CIE can show you how Patterns shown on TV and oscilloscope screens are simulated ELECTRONIC EXPERIMENTER S HANDBOOK If you want a career in servicing two way radio communications equipment you ll have to get a First or Second Class FCC Radiotelephone License One good way to prepare for your license exam is a specialized home study course from CIE the FCC License school There s a gigantic potential market out there for communications equipment service skills For example there are about 4 million mobile transmitters that are licensed by the FCC And that s just the beginning Radio systems are also used in air and railroad traffic control police fire fighting and rescue vehicles ship to shore communications dispatching of fleet vehicles such as taxis and trucks assigning field service specialists security networks satellite com munications and many other new and growing applications But before you can start a career servicing any radio system you must have at least a Second Class FCC Radiotelephone License How CIE Can Help You We ve been helping people prepare for the government administered FCC License examinations since 1934 Our record speaks for itself in contin
129. and junction address decode buffer box available WV IRCA sere ce crear ra td ene UR eb TER E 165 POLYMORPHIC VIDEO TERMINAL INTERFACE 96 character ASCII including lowercase and 32 special characters plus graphics Uses 7 x 9 char acter font 16 lines by 64 characters graphic resolu tion 48 vertical by 64 horizontal 128 optional Re quires 1 25 A 8 V 30 mA 16 20 V 20 mA 16 20 V For 32 64 character kit 210 280 8K MEMORY With provision for battery backup Kit wired er er oer E E e Ime 300 385 1 0 IDEABOARD Prototyping board for I O in blocks of four ad dresses Requires 8 10 V 370 mA excluding user added components Kit sssss 55 CPU 8080 processor with 4k RAM vectored interrupt real time clock space for up to 3k ROM 1k ROM monitor available Accepts inexpensive printer se rial and cassette interfaces Kit 215 Printer Interface Fits above MPU only RS 232 or 20 mA KI WNBOd Sor sva eder gre ERR NES 65 80 Cassette Interface For above MPU only Kansas City 300 or 600 baud and PolyPhase 1200 2400 standards Kit wired 0 0 c eens 65 85 PROCESSOR TECHNOLOGY GPM General purpose memory Combines 1k RAM 2k ROM or PROM space for 8k additional EPROM 2708 Required for use of ALS 8 SIM 1 and TXT 2 ROMS Kit wired 129 169 GPM Sol As above but without RAM and ROM K
130. ap in the volume when a signal is applied With S7 in the OrF position and S2 onouT the input signal atJ3 is applied to R7 and R8 and the output at J5 is half of the input This insertion loss is required to create the headroom needed for expansion When S7 is in the EXPAND position the photocell in O 7 is connected across H7 to vary the resistance of the upper half of the voltage divider This changes the output on J5 Poten tiometer R6 acts as a depth control to determine how much the variations in the photocell resistance affect the voltage divider 1978 Edition As the sampled signal increases re sistance of the photocell decreases increasing the output at J5 This pro vides the desired expansion When S1 is in the COMPRESS pOSi tion the photocell is connected across R8 so that as the sampled signal increases the output at J5 de creases The curves in Fig 2aretypical of the expansion compression effects Construction The complete circuit with the exception of transformer T7 can be assembled on perforated board The transformer should be lo cated as far as possible from the signal leads to avoid pickup The circuit shown in Fig 1 is for one channel except that the power supply can handle two channels for stereo Mount the various phono jacks and the two calibrate controls R70 and R11 on the rear apron suitably iden tified and the switches and depth potentiometers on the front panel The two
131. are of little use unless the leads and type pnp or npn can be determined Actually that s the only really important information needed to apply a transistor in a circuit assuming it is good to begin with Of course its nice to BY JOHN T BAILEY know what the transistor s beta is but this is not essential in many applica tions The Identometer was designed to provide a quick check of a transistor s leads and type It operates on the basis that bipolar transistors will operate but poorly if the emitter and collector leads are interchanged without also reversing the power supply Since a transistor has three leads it is possible to connect them in six different ways With a transistor plugged into the test circuit the identometer has a switch to make the six different connections When the right one is selected an indicator light comes on The light also tells whether the unit is npn or pnp Circuit Operation A schematic of the circuit is shown in Fig 1 Note that 77 has two secondaries one serving as the power supply for the Q1 LED1 and Q2 LED circuits and the other for the unknown transistor Transistor Q7 saturates when the upper secondary voltage is in the positive half cycle and its base is positive Transistor Q2 saturates when its collector has a negative voltage and its base is negative The two transformer secondaries must be in phase as shown by the small dots at terminals 1 and 3 The circuit is e
132. as fast as you can dream it up with Super Strips the faster easier Part Model Terminal and less expensive solderless breadboards from A P Number Number Type Products When you build your circuit on a Super 923252 Strip everything stays as good as new Once you re 923748 through you can use everything again and again In stantly Put a Super Strip to work for you Eight dis gold plated Order from your A P distributor today Our distributor tribution lines handle signal and power and 128 five list is growing daily For the name of the distributor tie point terminals can handle 9 ICs and then some nearest you call Toll Free 800 321 9668 It s a whole lot easier than printing a circuit Send for our complete A P catalog the Faster and and a whole lot handier than haywire Easier Book AP PRODUCTS INCORPORATED Box 110 Painesville OH 44077 216 354 2101 TWX 810 425 2250 You ve seen the rest so Solderless strips backing board and binding posts Everything you need to build and test your own circuit Used to be you d get a circuit idea lay out a pc board print it solder everything together trouble shoot change your layout try a new board and spend abso lutely too much time breadboarding Now A P ACE AII Circuit Evaluators let you breadboard in a fraction of the time Make your changes im mediately Keep full leads on your components Avoid the heat damage possibl
133. as inter record gap light full software or manual contro of all functions including fast forward and rewind has high speed search for inter record gap Comes with software Uses Uniboard cartridge drive construction Re quires serial I O port with two paralle bits for con trol 2SIO R board see below recommended for Altair bus systems Wired 220 00 CC 8 DIGITAL COMPACT CASSETTE RECORDER Direct digital recorder no audio cassette interface required using standard Philips type Compact Cas settes Handshake signals when motor is up to speed RS 232 1 O standard TTL optional user changeable speed adjustable Uses Binary NRZ asynchronous single track digital recording on half track format flip cassette over for second track Adaptable for 12 V operation Use of 2SIO R board recommended for Altair bus computers Motor ELECTRONIC EXPERIMENTER S HANDBOOK Start stop by remote or local control Fast forward and rewind Manual only Wired 175 2SIO R Altair bus board with I O connections for 3M3 CC 8 or audio cassette recorder one terminal in terface plus ROM monitor with read write search routines Kit wired E 160 190 NORTH STAR MPS A MICRO DISK SYSTEM Uses Shugart Mini Floppy drive 100k bytes per dis kette Controller on one Altair bus board with boot strap software in PROM Supplied with DOS and disk BASIC software all connectors an
134. ata transmission by pong UU uL PLA T 995 Cassetterm Similar to Pocketerm but with built in mini cassette data recorder to store data for high speed transmission via built in acoustic coupler a e Ml aM x cC 1445 MICRO COMPUTER DEVICES SELECTERM IBM Selectric I typewriter adapted for use as print er for computer output Uses ASCII code parallel port interface Supplied with ASCII character ball 31 other type font balls available including OCR Script and italics Full upper and lowercase Re tains IBM warranty and is still usable as typewriter though keyboard does not communicate to comput er Standard is 10 char in 13 in writing line 12 char in 155 line available on special order no ex tra charge Wired and tested 1295 Dual pitch option 10 and 12 char in 100 Correction feature ssseeessssem 100 Computer controlled backspace n 25 Computer controiled index vertical tab 25 MICRO DESIGNS MODEL 100 FORMATTED DIGITAL CASSETTE 109 SSSRIILLBULLLLELLLLLLELELEIULLETUULLLPYVOLLTT LEE ALLE TIL LZ Digitally controlled single drive transport and inter face for standard Philips type compact cassettes Stores one half megabyte per cassette transfers data at 1000 bytes sec searches for individual re cords at 120 in sec under 28 sec per side with C 60 cassette Tape transport under computer control COS software allows file man
135. ate increases through the earphone When you are sure that the circuit Is operating properly attach the two ac tive leads to an area over a forearm muscle and attach the shield lead with its electrode to an area such as the wrist where there is little muscle activity The two active leads should be attached to high quality low noise electrodes such as a disposable or permanent silver silver chloride type The shield of the electrode cable is the reference lead and should be con nected to a low cost electrode Such as stainless steel The electrodes are held in position with tape or some other type of adhesive With the MODE Switch on ACTIVE ad just the INTEGRATION control to 0 5 s and set the SENSITIVITY control to its minimum Slowly increase the latter while flexing the forearm muscles Observe the change in indication on the meter and in the frequency of the audible signal Make a note of the SENSITIVITY setting when the arm is re laxed Try the approach once more this time trying for a lower relaxed reading by changing your thoughts and mental attitude Move the SENSITIVITY control up slightly and try again to relax the forearm to reduce the indications to zero Repeat this operation with the SENSITIVITY increased again A regular daily routine works best practicing between 15 and 30 minutes a day on muscle areas that give you aparticular problem such as the forehead if you have tension headaches Keep a rec o
136. attachment of test probes components or an additional connector Intra Switch plugs right in line too But small dependable slide switches are built Faster and easier is what we re al about AP PRODUCTS INCORPORATED Box 110 72 Corwin Dr Painesville OH 44077 216 354 2101 TWX 810 425 2250 CIRCLE NO 1 ON FREE INFORMATION CARD 1978 Edition NNECESSARY muscular tension is known to be one of the con tributing factors to psychosomatic ill ness Unfortunately much of this muscular tension is subconscious so many people can t relax because they arent aware of the tension Conse quently many methods have been de visedto provide recognition of tension and encourage relaxation including yoga and autogenic training biofeedback techniques To detect muscular tension scienti fically it is only necessary to measure the minute electrical signals gener ated by a muscle when it is working This is done by an electromyograph EMG The EMGhas electrodes which are placed in intimate contact with the skin over a given muscle When the muscle is under tension the EMG pro vides either a visual meter or audible indication of the muscle tension The person to whom the electrodes are at tached then becomes part of the feed back loop through his eyes or ears and can try to reduce the tension by mental or physical means With this elec tronic aid a person can learn to elimi nate or greatly reduce the tension
137. ave signal across H1 is amplified and applied to a meter readout through a full wave rectifier Audio Use Photoconductive cells can be used in many fascinating experi ments and money saving conveniences in audio work The circuit shown in Fig 4 for exam Fig 3 Electromechanical light chopper has rotating aperture wheel amplifier meter OUTPUT Fig 4 Photocell feedback for audio effects Fig 5 Solar cells in series parallel array HEADPHONES ZK POWER SWITCH SPST O SELECTOR SWITCH SPDT ple provides light controlled feedback of an audio amplifier If the intensity of the lamp controlled by S1 is sufficient to lower the resistance of the photocell part of the amplifier s output signal is fed back to the input Depending on the lamp s brightness which is set by poten tiometer H1 powerful feedback oscilla tions of variable intensity can be ob tained Thus the amplifier can be con verted into a single frequency cue generator an aid when cutting master tapes If desired the amplifier can trigger a special effects instrument The photo cell can be activated by the dominant light of a color organ during original deep bass sequences with the photo cel s output triggering a solenoid operated drum In the circuit shown in Fig 4 R2 pro vides a keep alive current path for the cell Since its own resistance is high no feedback will ensue unless resistive circuit values are
138. back them off about 13 turns Set R17 to its midposition and set R16 to its maximum value Apply power to the Minivolter Ad just the potentiometer across the meter until the meter gives an up scale reading Then adjust R13 and R14 to make this reading a minimum Progressively increase the value of the meter shunting potentiometer and adjust the two trimmer poten tiometers to obtain a zero until the shunting potentiometer can be re moved from the circuit Trim R73 and R14 a final time 45 46 RI 100M 100V R2 50M 50V H R3 IOM lov R4 SM 5V R5 IM tV R6 500K 500mv R IOOK 100mv R8 50K 50mV R9 IOK lOmvV RIO 4 5K 5 mV RII 500n Imv PARTS LIST Bl B2 6 AA cells each D1 D2 1N914 diode IC 1 IC2 741 op amp J1 Phono jack M1 0 50 LA meter Radio Shack No 22 051 or similar Following resistors are 2 watt 596 R1 100 megohms five 20 megohms in series R2 50 megohms five 10 megohms in series R3 10 megohms R4 5 megohms R5 1 megohm R6 500 000 ohms R7 100 000 ohms R amp 8 50 000 ohms R9 10 000 ohms R 10 4500 ohms two 9100 ohms in paral lel Ril R12 500 ohms R13 R 4 10 000 ohm miniature mul titurn trimming potentiometer RI5 5000 ohm miniature multiturn trimming potentiometer R16 50 ohm miniature multiturn trim ming potentiorneter R17 1 megohm potentiometer SI Single pole 12 position rotary switch
139. batter ies to provide many hours of play Game Operation The game is played by two people who alternate as Pitcher and Batter The pitcher s arsenal consists of a left curve right curve and straight balls Each can be slow fast or one of two changeups a total of 12 dif ferent pitches The ball is thrown and travels its pitcher determined route to end up over home plate The batter must decide from which direction the ball is coming and hit it as it passes over home plate by depressing a switch cor responding to that direction i e left center or right bat if the batter swings too early or too late it s a strike If the batter hits the ball and keeps the bat depressed a hit will be displayed The type of hit single dou ble etc is chosen essentially at ran dom but the batter s chances for each type of hit are the same as an average 300 major league hitter To make the game more realistic and interesting the batter can also hit into a double play counts as one out if no men are on base If the batter tries to cheat and depress more than one bat simul taneously more than one home plate LED will light indicating that a foul ball is to be counted A control on the playing field allows the players to decide if they wish to play in the Little Minor or Major leagues You can also add an option that provides an audibie signal a short beep each time someone gets a hit RI8 CI3 RI6 3 S28
140. battery 2 AA C or D cells RFCI 2 5 mH r f choke CI C3 t pF 10 volt electrolytic capacitor S1 Spst switch T1 1000 ohm transformer Misc Battery holder PC or perf board mounting hardware For probe 50 000 ohm V watt resistor 25 pF capacitor IN34 diode shielded cable phono connector J1 J2 Phono connector miniature Q1 Q3 2N 107 transistor R1 100 000 ohm V watt resistor R2 4700 ohm Y2 watt resistor R3 47 000 ohm Y2 watt resistor R4 15 ohm V2 watt resistor RS 33 000 ohm V w att resistor PR DLL oix cD di bp u SS a C EE e ia I ES ae SS RS cn t primary output come in handy For example there are harmonics at 1368 and 1596 kHz for aligning the high end of the dial while the harmonic at 684 kHz is useful for the low end Audio Amplifier The circuit shown in Fig 3 is a conventional high gain audio 72 amplifier having a selection of one or two inputs The input at jack J2 is for conventional audio while the input at J1 is for an r f demodulator probe This is also shown in Figure 3 This composite circuit can be used to check a radio from the antenna input through the final audio section Construction The circuits can be as sembled either individually or combined on either perf board or printed circuit board They can all be mounted in a common chassis with pertirient switches and connectors on the top
141. binet power supply card rack and back plane for Wince modules plus one RS 232 adapter for control board s serial port With four module backplane and power supply DO MY S CEU Ned Fees E CN DIC ERAN E M UN 599 With eight module backplane and power supply QN MR M uh Mid LL ect ee 728 8080 MPU SYSTEM Totally modular on 34 x 4 plug boards Mount in card files with from seven to 28 slots in cluding 19 in rack mount versions or 84 slot card drawer for 19 in rack System options include RAM and EPROM memory parallel serial analog and opto isolator I O priority interrupt time clock front panel interface for DEC PDP 11 power supply pa per tape reader wrapped wire module plus a wide variety of plug compatible individual logic modules Price depends on system configuration ZILOG Z 80 MCB Z 80 MPU single board computer with 4k RAM 16k optional 4k ROM or PROM monitor firmware available in 2k 1k 2k and 4k versions 4k stand ard serial port parallel 1 0 Wired 495 Z80 RMB 16k RAM board 4k provided 750 Z80 CPB PROM Programmer for 2708 and 7620 ME Mn UE as Renee 575 Z80 VDB Video display board 24 lines x 80 charac ters uppercase ASCII eerren 475 Z80 IOB Four port parallel I O oe 350 Z80 SIB Serial O board four full duplex ports ah ToS ne E A CR ERU TRE ae Ter eee S 375 Z80 MCS System with card cage power supply 16k RAM 3k PRO
142. board in separate housing Basic sys tem includes 11k ROM including BASIC and moni tor plus space for 21k additional 16k RAM 8k re served for screen refresh and scratch pad 8k user available plus space for 16k additional 31 ports of 512 available implemented including two RS 232 serial and two parallel ports baud rates from 110 to 76 8k Video display 80 characters x 48 lines 64 ASCII characters plus 32 lowercase ASCII with de scenders 160 192 graphics with software for vec tor bargraphs and point plot white blinking over score underscore nondestructive cursor eight fore ground colors independent of eight background col ors editing features including erase page erase line cursor positioning page roll mode insert delete character line Programs on continuous loop 8 track Floppy Tape cartridge 4800 baud with RS 232 serial interface With single Floppy Tape Hdrve red M M E 2750 With dual Floppy Tape drive 2995 Additional 8k RAM l sese 375 Light Pen factory installed 550 Numeric Keypad factory installed 90 16 Special Function Keys factory installed 300 Single Floppy Tape drive capacity 16k bytes 250 Dual Floppy Tape Drive aa n 450 Compucolor Mini Desk Drive to 110k bytes 750 Dual Mini Disk Drive sssssesnRe 1250 COMPUTER POWER AND LIGHT COMPAL 80 8080 MPU computer includ
143. cabinet and power cord P 389 UC1800HK Parts kit including PC boards keyboard crystal ROM MPU readouts cable and manual requires additional commonly available parts SDK 80 Single board 8080A MPU computer with serial and parallel I O power on reset 256 byte RAM memo ry 1k ROM monitor connectors for off board ex pansion and pre drilied areas for system expansion on board Kitonly eec ccs cete a een ccs 250 INTERSIL INTERCEPT JR Tutorial microcomputer system using Intersil s IM6100 CMOS 12 bit microprocessor and related CMOS devices Uses DEC PDP 8 E instruction set Multi function octal keyboard and octal display In cludes 1k x 12 ROM monitor plus socket for addi tional ROM 256 x 12 bit CMOS RAM On board battery for battery operation or non voiatile memory connections for external 5 V or 10 V supply 6950 EN dT 281 6951 1k x 12 CMOS RAM module with battery Datkupue s E I ME 145 6952 2k x 12 ROM PROM module 75 6953 Serial I O RS 232 or 20 mA with ROM boot strap for OEC BIN format media 82 6957 Audio visual module with switch register input binary and octal readouts volume controlled speak lae ERU T 125 LOGIC DESIGN LD14 LABORATORY DESIGN COMPUTER Digital logic computer architecture training comput er Pushbutton controls and binary LED displays for all functions and signals Breadboa
144. cent channel interference The only problem was thal the focal oscii lator would slowly drift off frequency producing a beat note which made re ception intolerable One member of the group then theorized thatif the oscillator frequency could be compared to tna signal tre quency in a phase detector circuit a correction voltage could be produced ta return the oscillator This could be done by having the correction valage drive a Miller effect electronic vari able capacitance amplifier connected across tha tuning circuit of the oscil lator The same feedback idea had worked in servo systems So why not an electronic servo The new oscillator circuit was Built and connected to the receiver system it not anly stayed in frequency with the incoming signal it locked itself in When the tuning was changed to a new o Fig 4 Lock range versus input signal level for the 565 phase locked loop signal the oscillator would hold onto the ald until the new one got too strong and then it would switch to the new signal When the system was tuned be tween carriers it hunted for th sironger one and locked on to it The receiving system which origi nally had been named the homodyne circuit was renamed the syncrodyne circuit The circuit though superior to the superhet in many ways could not com pete where cost was Concerned The oscillator locking circuitry was too ex pensive Though the syncrodyne r ceive
145. commodate a variety of mod ules MPU module normally uses 6502 but can be fesi cunLiencen f configured for 6800 6501 or 6512 additional MPUs may be used under main MPU s control with 460Z board Typical system 65V AK includes 6502 MPU video output for 32 x 32 alphabetic 4k RAM PROM monitor one parallel port case and power supply 65V 4K Wired sse ord 675 Dream Machine 65V 4K with 16k RAM single drive floppy disk disk bootstrap PROM keyboard termi nal Sanyo CRT monitor for 16 lines of 64 charac ters BASIC DOS and assembler editor on dis KellE ees dint Sete aC Mp 2599 With serial port for external terminal less keyboard CRT monitor and video interface 2099 Graphics Option 128 x 128 eee 125 Serial Interface Option sessssssenee 100 4k Memory Board kit wired 29 129 149 Challenger Cassette Interface Kansas City standard expandabie to include parallel I O eight channel A D two channel D A when fully populated 430B Board wired for cassette fully populated x IL M tr IS 29 89 349 Video Graphics Video output for 32 x 32 alphabet ics capable of 128 x 128 and color graphics and animation with addition of memory chips Board kit scene dM Co ce PON FE S 29 129 PROM Boards unpopulated 450 Includes on board programmer parallel i O port accepts up to 8k PROMs 6834 29 455 Includes parallel
146. connectors are industry standard two parallel rows of contacts spaced every 1 Great Jumpers come in five popular cable widths 20 26 34 40 and 50 lines wide and in lengths ranging from 6 to 36 Available now at the distributor near you who car ries the A P Products Faster and Easier Line Our distributor list is growing daily For the name of the distributor nearest you call Toll Free 800 321 9668 Send for our complete AP catalog the Faster and Easier Book X Faster and easier is what we re all about S 4 r L AP PRODUCTS INCORPORATED Box 110 72 Corwin Drive Painesville OH 44077 216 354 2101 TWX 810 425 2250 Connect with a little help from Intra Connector E ST Intra Connector and Intra Switch do right in to switch each line independently So it s for flat cable systems what our IC Test great for diagnostic and quality testing terrific for Clips do f DIP hich d lot programming or selective line inhibiting Ips ao for S which Can do a lo Intra Connector and Intra Switch are available for you in 20 26 34 40 and 50 contact versions at the dealer or distributor in your area who stocks our I V bun M mates e with E a Faster and Easier Line You can locate him by call ouble row socket connectors It has one set of fe ing our toll free number 800 321 9668 male contacts but two sets of male at right angles So it provides instant line by line probeability and allows for
147. correct time Well with this automat BY JOSEPH GIANNELLI ic exposure controller you can have such a device for much less than you would pay for a professional unit The controller is a unique new device for the amateur photographer A search through camera catalogs and visits to photo suppliers will quickly reveal that the only thing remotely resembling this device is the simple light meter and the resemblance is remote indeed You can build the automatic exposure controller for about 22 How It Works The sensor used in the controller LDR1 in Fig 1 is sensitive to the entire visible spectrum adapting the PARTS LIST Cl 1 pF 25 volt electrolytic capacitor C2 250 pF 25 voit electrolytic capacitor C3 C4 1 wF 25 volt Mylar capacitor C5 2 pF 25 volt Mylar capacitor D1 D4 1N458 diode F 1 ampere fuse IC 1 NE555 timer IC Signetics J1 Phono jack insulated from chassis K1 12 volt 1640 ohm relay Sigma No 65FP1A 12DC LDR1 Light dependent resistor Clairex No CL9OOSHL PL 1 Phono plug Q1 MPF 102 n channel field effect transistor Motorola R1 R3 100 ohm l2 watt resistor R2 See text R4 15 000 ohm 2 watt resistor R5 100 000 ohm l2 watt resistor R6 2400 ohm V2 watt resistor R7 500 ohm linear potentiometer S1 Spst switch S2 Spst normally open pushbutton switch S3 3 pole 3 position nonshorting switch Centralab No PA1006 SOI SO3 Chass
148. crolling or page mode operation upper and lowercase characters with Switchable lowercase defeat reversed character printing control charac ter printing with defeat switch cursor control com plete controt character decoding Usable with any eight bit ASCII computer With power Supply key board serial interface beeper chassis and cover See ae ere c UM 325 CT VM Video monitor for above in matching case Requires CT 64 s power supply Wired 175 AC 30 AUDIO CASSETTE INTERFACE Interfaces between computer and termina requires accessible 16x clock and 300 baud rate RS 232 serial Provides independent control for two record ers including automatic start stop either cassette may record while the other plays back data LED in dicators display record read status and data flow Local remote switch permits using recorder with terminal alone Kansas City standard Kit 80 GT 6144 GRAPHICS TERMINAL Cell array is 64 wide by 96 high each cell addressa ble by computer programming allows fixed or mov ing images Data can be loaded in less than 2 usec Image reversal for white on black or reverse stand ard 525 line format 6144 bit static RAM Operates with any computer whose parallel interface outputs an eight bit word and data ready strobe this in cludes any 8080 or 6800 machine Does not include chassis or video monitor Programming allows dis play of graphics CT 1024 alphanumerics or com bi
149. ction it is sug gested that you use a socket with C1 do not solder directly to the IC pins A 3 4 SOLDER EDGE OF PROJECTED IMAGE 9 0 me CENTER WITH FILLER SOLDER 42 41 4 OVERALL LEICA EASEL ADAPTOR 2 COND SHIELDED Mount J1 H7 SO1 SO3 and S1 S3 on the top half of the case and route the line cord through a grommet lined hole as shown in Figs 3 and 4 Connect the earth ground green power cord wire to one of the mounting lugs of 71 and case ground Note In the prototype no pow er Switch was used But the use of ST mounted to the case top and connected in series with the black power line lead and F1 is recommended Details for fabricating the cell bracket for LDR1 are shown in Fig 5 Use only solderable brass or copper tubing You can make the cell holder as shown cut ting and soldering it as required Alterna tively you can fill the tubing with dry sand or slide into it a tubing bender spring and heat the tubing just enough to permit its bending without crumpling Either method should yield the same re Fig 5 Details of the cell bracket which holds LDR Tubing is brass or copper obtainable in hobby stores and painted black sults with respect to orientation over the photographic paper when the bracket is mounted on the easel After drilling and deburring the cable exit hole and soldering the tubing to the modified Leica easel adaptor spray the entire assembly
150. d a final one for Figure Address Outputs Segments Displayed A A B B on 0 00000 00111111 abcdef 1 00001 00000110 bc 2 00010 01011011 abdeg 3 00011 01001111 abcdg 4 00100 01100110 bcfg 5 00101 01101101 acdfg 6 00110 01111101 acdefg y 00111 00000111 abc 8 01000 01111111 abcdefg 9 01001 01101111 abcdfg 01010 10000000 decimal point 01011 01000000 g 01100 01001000 dg A 01101 01110111 abcefg b 01110 01111100 cdefg C 01111 00111001 adef C 10000 01011000 deg d 10001 01011110 bcdeg E 10010 01111001 adefg F 10011 01110001 aefg a 10100 00111101 acdef H 10101 01110110 bcefg h 10110 01110100 cefg E 10111 00010000 e J 11000 00011110 bcde L 11001 00111000 def n 11010 01010100 ceg O 11011 01011100 cdeg P 11100 01110011 abefg i 11101 01010000 eg U 11110 00111110 bcd ef u 11111 00011100 cde These letters are only approximations included only to use up the PROM s program capability mines the number of address input and output lines that will be available in a given ROM Address input pinsare the means by which a specific word in the memory is accessed or selected If a particular ROM is organized with 32 words of eight bits per word each word can be addressed with five input address lines 2 32 The address 00000 would be for word one 00001 for word two 00010 for word three and so on until 11111 would be for word 32 The number of output pins for a small memory is determined by the n
151. d cables Power requirements 9 At 5 V 1 6 A 12 V can be supplied by computer or optional power supply Drive assembled controller available kit wired m e 699 799 Power Supply 000 0 0 00 0 0 0 000eccc eee T A 39 Cabinet m 39 Additional drive a an M 425 OHIO SCIENTIFIC FLOPPY DISK For OSI Challenger 400 series or 500 series com puters Singie drive unit available kit or wired with cables controller board bare in kit version and disk operating system on diskette BASIC available Dual drive unit wired only Single kit wired dual wired T 599 990 1590 Floppy Disk bootstrap PROM optional eee 60 OLIVER OP 80A PAPER TAPE READER High speed optical tape reader no moving parts Reads punched paper tape up to 5000 char sec In cludes optical sensor array high speed data buff ers handshake logic for interfacing with parallel I O Kit wired TM TT 75 95 2708 16 PROM PROGRAMMER Programs 2708 and new 2716 PROMs Interfaces to parallel port requires very little software data is dumped via the output port to program the ROM Requires 1 A 8 12 V power supply Takes less than 100 seconds to program 2708 less than 200 tor 2716 Kit wired osos 249 299 Kit less regulators o sos sse 199 PAIA 8782 DIGITALLY ENCODED KEYBOARD Piano type 37 note keyboard for computers and electronic music systems Includes power supply and softwar
152. d pc board for the timing light 1 40 are available from Anthony Caristi 69 White Pond Rd Waldwick NJ 07463 Fig 1 The de to de converter TI steps up the battery voltage Label one end of a 4 ft 1 22 m strand of the enameled wire with a 4 Label one end of a similar strand 5 Starting with these two ends together wind 27 turns of both wires on the bobbin Using an ohmmeter determine the unmarked end of the wire that started with 4 and connect it to the end marked 5 This is the center tap The other unmarked end is terminal 6 Cover the winding with tape to hold it in place and insulate it from the sec ondary The secondary winding consists of 240 turns of No 36 enameled wire This is the most tedious part of as BATT TI T 48 Ss R3 7 D2 7 Fige Foil pattern is above component placement left FTI sembly Be sure to accurately count the number of turns as you go How many turns you wind will determine the dc potential applied to the flash tube When you are finished winding attach 5 in lengths of stranded hookup wire to the winding ends and label them 7 and 8 Then wrap the turns with tape Now you can begin assembling the circuit proper A printed circuit board is recommended for component mounting see Fig 2 for actual size etching and drilling guide and com ponents placement diagram Transformer T1 is mounted on the board with the aid of a 6 32 x 1 in mach
153. ding word repeating steps 3 through 7 as you proceed from word to word until you have com pleted programming the PROM The schematic diagram shown in Fig 2 depicts a program and test cir cuit As you finish steps 3through 7 for each word set S2 to TEST dO not change the address code yet and ob serving the meter check the PROM Ss outputs by cycling through S3 s posi tions Logic 0 will be indicated by the pointer swinging to near the scale s zero index while logic 1 will be indi cated by about a 5 volt reading Once you have verified that the pro gram has taken fora given word set up the circuit for programming into the PROM s memory the next word that you want After making sure that the PROM is properly programmed affix some identifying code on its case and truth table and file away the latter in a safe place where it will not get lost e 23 rene se LOW COST COMPANDER ENHANCES HI FI RECORDINGS BY CRAIG ANDERTON Simple accessory expands or compresses playback s dynamic range Ss the dynamic range of live music is usually greater than the range that discs and tapes can handle it is standard practice to introduce a certain amount of level compression when a recording is made Unfortu ROMS R2 270 Cl F 220pF RI 500120 l R3 2200 IN4O0 RI2 56011 D4 IN400i 24 nately this compression limits many crescendoes and percussive tran sients that add to the enjo
154. disk transfer rate 125k bits sec Requires two slots in Altair bus for controll e Wisdom MINE S 1150 ALTAIR C 700 PRINTER Matrix impact printer up to five copies prints 132 columns of 5 x 7 dot matrix characters 64 charac ter ASCII uppercase 10 characters per inch at a rate of 60 char sec 26 lines min Character width adjustable to provide 66 columns of double width characters Printed lines spaced six lines in Prints bidirectionally to save carriage return time Inter face requires one slot in the Altair computer bus ss JL RRNA Ene APRA vole d RNa Nr M Cuter Ren ce 2375 SSSSAIATHLUAUHUEH BLUT AGREE EET i 110 CIRCLE NO d S WHAT S YOUR BAG Or XY try our DESIGN A KIT for a great way to customize your Own kits Take your pick from our 10 000 item inventory FREE CATALOG TECHNI TOOL nc Apollo Rd Plymouth Mtg Pa 19462 215 825 4990 SZTUNAGLABULAPYLLNL ELLO LL DOULLELDILELEBUHEL EDD EL SA pg t A E ERIT LA NY 24 ON FREE INFORMATION CARO ws Whatever it is we ll fill it FN OS with anything and everything Choose from a complete line of specialized tool kits and cases 48MM AMAN IAALLLLLLLLLLLLLULEELLLLTELITHLLLHANLLLLLURLLLELLI ALTAIR 7000 GRAPHICS PRINTER Prints upper and lowercase characters or graphics on electro sensitive paper Requires one parallel port plus MITS Extended or Disk Extended BASIC with 7000 option listings of plotting subroutines supplied
155. e but single board version less power supply cabinet keyboard but with 2k RAM Kit wired Duc LM DN CNN 575 745 Personality Modules Firmware optimizing SOL sys tem for particular applications SOLOS 2k for stand alone computer use SOLED 2k for use as editing terminal Either included in price of SOL SOLOS or SOLED Kit wired 9150 8175 CONSOL 1k personality module Available with SOL kit computers for 100 less than above kit prices QUAY 90 MPS 2 80 MPU single board computer with on board EPROM programmer Features 4k to 64k on board RAM in 4k or 16k increments 2 5 MHz clock 1k EPROM monitor expandable to 7k EPROM total 32 to 64 I O lines one serial RS 232 20 mA inter face up to four parallel ports support Z 80 vectored mode four programmable counter timers support Z 80 interrupt External bus signals accessed via DIP 60 pin connectors Requires 5 V t 3 5 5 A 5 Vite 100 mA 1 5 A 12 V 300 mA 3 A and 28 V tu 200 mA for PROM 2708 programmer 90 04MPS With 4k RAM 32 1 0 lines 695 94 04MPS Same with 4 MHz clock 795 1978 Edition 90 16MPS With 16k RAM 64 I O lines four pro grammable counter timers 2 5 MHz clock 1295 94 16MPS Same with 4 MHz clock 1395 80AI Altair bus compatible Z 80 based computer includ ing one serial interface RS 232 20 mA one paral lel keyboard input Automatic baud rate setting 1k ROM monitor sockets for 3
156. e requir BY GEORGE A ELLSON Circuit is triggered on and off bv a flashlight s beam ing only an ordinary flashlight to trig ger it on and off The system will con trol virtually any load rated at up to 4 amperes or 450 watts About the Circuit Transistors Q1 and Q2 in Fig 1 form a regenerative bistable switch using Q3 as the col lector load for Q2 The voltage across R8 is high when Q3 is cut off and low when Q3 is saturated The condition of Q3 depends on the voltage at the base of Q7 which is in turn dependent on the resistance of the LDR1 LDR2 volt age divider Light dependent resistors LDR1 and LDR2 are photosensitive devices When their active surfaces are dark their resistance is at max imum However when the surfaces are illuminated the resistance de creases the amount of decrease governed by the intensity of the light If both LDR s receive the same amount of light the base bias of Q1 remains the same Now if only LDR1 is illuminated its resistance drops and causes Q1 to go into cutoff But if only LDR2 were to be illuminated its change in resistance would cause Q7 to go into saturation The fast re generative action of the circuit will then cause Q3 to go into saturation or C1 100 LF 15 volt electrolytic capacitor D1 200 PIV 500 mA silicon rectifier 1N647 or similar D2 9 volt V2 watt zener diode 1N960 or similar F1 4 ampere fuse LDRI LDR2 Cadmium sulfide light
157. e tracks is determined by the setting of potentiometer R2 To adjust R2 de press increase speed switch S7 for 10 seconds The glow of the three lamps will increase in brilliance during this interval Set R2 for the desired upper limit track voltage The speed at which the track voltage increases and decreases is deter mined by the two current pumps Q3 and Q4 With the components specified in the Parts List the voltage change rate is about 2 volts second Increasing the values of R3 and R4 decreases the rate of change and vice versa e So why should the experimenter have to start from scratch when we can give it to them in kit form ELECTRONIC EXPERIMENTER S HANDBOOK 1978 Edition Identifies leads on unknown transistors indicates PNP er NPN polarity and shows up bad devices BUILD THE h ECBBCE Pratt el L BBECEC S Litil S a a AA my nis Pe ET T ee 4j TEVERIL FI II har rg i i ri undas pP 2 T n v a VLDE ES vut E amp e a T x ae hee 5E ird Fes a Pi r i ee j pd y md gy S i DR j ay AEN Aes E ath rM E Eu A i S E Er f p AINELE Bites A i uh a ik et ae D Mtr AH j zt Pr i Wer Ek L Oe eae ns c os Ms i a P p ay ie ro Le tS fhe f si r me f J y p TOMETER OST experimenters have a drawer full of unidentified tran sistors which
158. e 0 1000V Freq Response 50 400 HZ DC AC Current 0 1000mA Resistance 0 10 meg ohm Size B4x44 2 Model 2800 AC Adapter BC 28 Rechangeable Batteries BP 28 Carrying Case LC 28 DATA HANDBOOKS 7400 Pinout amp Description of 5400 7400 1C5 2 85 CMOS Pin out amp Description of 4000 Series ICS 2 95 Linear Pin out amp Functional Description 2 95 ALL THREE HANDBOOKS 6 95 ZENERS DIDDES RECTIFIERS wg 99 95 8 00 20 00 6 00 Cames with test igads Operating manual and SPare fuse TYPE VOLTS W PRICE TYPE VOLTS W PRICE 1N746 33 400mm 4 100 1N4005 600 PIV 1 AMP 10 1 00 IN7SIA 51 400m 4r DG 1N4006 800 PIV 1 AMP 10 1 00 18752 56 400m 41 00 1N4007 1000 PIV 1 AMP 107 00 1N753 52 400m 4 4 00 1N3600 50 200m 6 1 00 14754 68 400m 4100 mNat4B 75 10m 155 00 1N959 82 400m B100 1N4154 35 10m 12100 1N965B 15 4O0m 4100 N4308 75 25m 20 1 00 1N5232 56 500m 2B 1N4 34 56 Iw 28 1N5234 62 500m 2B N4735 B2 iw 28 1N5235 58 500m 28 184736 68 1w 28 1N5296 75 500m 28 1Na798 82 iw 28 1N4556 25 40m 81100 TN4 42 12 lw 28 1N458 150 m 6 100 1N4744 15 iw 28 1N485A 180 10m 6100 1N1183 50 Py 35 AMP 180 1NAQ01 50 PN t AMP 12 100 181184 100 PIV 35 AMP 170 1N4002 100 PiV 1 AMP 12100 1 N1185 150 PIV 35 AMP 150 1N4003 200 PIV 1 AMP 12100 11186 200 Piv 35 AMP 80 1N4004 400 PIV 1 AMP 1N1188 400 PIV 35 AMP 3 SCR AND FW BRIDGE RECTIFIE
159. e independent power supplies are conventional bridge rectifier circuits PARTS LIST CI C2 1000 uF 50 volt capacitor C3 3500 uF 75 volt electrolytic ca pacitor F1 F3 5 ampere 3AG fuse and holder 1 I 117 volt neon lamp assembly RECTI RECT3 MDA 920A 3 rectifier R1 R2 3900 ohm 2 watt resistor R3 10 000 ohm 1 watt resistor S Dpst switch electrolytic bridge TI T2 Transformer 24 V 1 A Triad F46X or similar T3 Transformer 40 V 1 A Triad F92A or similar Misc Suitable cabinet Bud CU7127 or similar aluminum panel 4 thick Bud PA3102 or similar heat sink 3 x4 x mounting hardware line cord power transistor insulators ter minal strips capacitor mounts knobs etc The C5 capacitors in the low voltage supplies and C3 in the high voltage supply should be mounted directly on the output binding post behind the front panel Use tie points to hold R77 and R72 in the low voltage supplies and R13 and A74 in the high voltage supply Checkout Check the rectifier cir cuits before connecting all the rest of the circuits If the rectifiers are all right connect the regulator circuits It is strongly suggested that when first testing the high voltage supply a Variac or similar source be used to provide alow voltage input at the start An oscilloscope should be used to detect any tendency of the supplies to oscillate This should be done at sev eral Current and voltage outpu
160. e instructions Can be used as infinite hold Sample and Hold device with PAIA 8780 D A converter Kit ee ee 8780 DIGITAL ANALOG CONVERTER Equally tempered D A converter based on multiply ing principle rather than conventional ladder type 1978 Edition circuits to generate Stair step exponential function required for equally tempered musical intervals Generates over five octaves of contro voltage from only six bits of data remaining two bits usable for trigger flags range extensions or micro tonal tun ing Interfaces to any microprocessor with or with out handshaking logic Can be used with 8782 key board for infinite hold Sample and Hold Kit 35 In addition to computer above modules interface to a complete series of synthesizer module kits PERIPHERAL VISION FLOPPY DISK Floppy disk system with 300k bytes formatted and Altair bus controller Hard sectored Controller for up to eight drives can load head of more than one drive at a time for more efficient file copying Inter face card has bootstrap in ROM jumper address to any 8k boundary Includes DOS on disk with source listing FLHS KC1 AC1 Complete assembled drive and in terface Kit wired ooo 750 850 PWR 1 K A Power supply for above Kit wired rr D ee P 45 65 CBF 1 Single drive Cabinet sssse 85 FLHS P 1 Hard sectored floppy drive only 550 iFF Floppy interface card with software Ki
161. e left at home comforts that can only be provided by electrical appliances Unfortunately appliances that work on 12 volts dc are relatively expensive You can however use a dc to ac inverter enabling you to utilize ac equipment you already own As some readers might have already discov ered though most of these devices deliver a form of Square wave that pre vents their use with equipment that is 1978 Edition 666 9 16660 sensitive to the interference caused by square waves This includes TV re ceivers audio equipment CB gear and some test instruments With the inverter described here you can now get 117 volts of 60 Hz sine wave power at 100 watts from a conventional 12 volt battery system In addition the in SPECIFICATIONS Input 12V dcat 14 A Output 117 V ac 50 400 Hz 100 W Distortion Less than 10 at 100 W Charge Current 15 A max self limiting Build A I Boosts 12 volts dc to 117 volts ac at 100 watts and also recharges storage batteries BY MARTIN MEYER verter can be used to recharge vehicle batteries at 15 amperes from any 117 volt 60 Hz power source The inverter can also be preset to deliver power at any frequency from 50 to 400 Hz making it useful for operating some surplus electronic gear designed for 400 Hz As an integ rated standby power source it can even be used for power failure emergencies in the home How It Works As showninFig 1 the f
162. e pc board as shown in Fig 2 These are for possible use in ad vanced projects For normal opera tion no connection is necessary at these points Point T provides a TTL level signal to facilitate interfac ing with external digital circuits By connecting point E to ground the 1 MHz oscillator is disabled and an ex ternal oscillator can be applied to point C An external reset pulse can be applied through point R to reset the scan counters at any point in the scan cycle Since both position and intensity information are available in digital form Cyclops can very easily be interfaced with a digital computer Photo shows chassis with the printed circuit board pulled out 90 The external oscillator input can be used to synchronize Cyclops with the computer or with a TV display Construction The logic circuits of Cyclops are on a single pc board Fig 3 Use sockets for all of the IC s ex cept C70 which is soldered in place Be sure to observe the correct polarities on all IC s diodes and tran sistors For the pilot lamps 7 and 2 drill holes in the board justlarge enough to accommodate the metal portions of the lamps so that when they are in serted from the nonfoil side the glass portion just touches the board The metal portions of the lamps are then soldered to the pads and small lengths of wire are soldered to the center connectors on the lamps and the appropriate pads Miniature potentiomete
163. e with repeated soldering and de soldering A P made the first modern solderless breadboard and we still make them best SEMEN UU D e p a P P MPEDEEEMDEEGSGERQE IELLLCQLLGLULuLLLULGLCILLLGCGCEOLLLLULGCL C GGLLLSGI CGGGRG RIOUNGEELZLZLILLIOLLLALLILLE XLLEA AGLLOLILLLVLISALRLD CL IOBOAMMMMMGILRLSTLL Pick an ACE for Faster and Easier solderless circuit Send for our complete A P catalog building and testing The Faster and Easier Book 923333 200 K kit 8 16 s 4 9 16x5 9 16 923332 208 assem 8 16 s 4 9 16x5 9 16 923334 201 K kit 12 14 s 4 9 16x7 923331 212 assem 12 14 s 4 9 1627 923326 218 assem 18 14 s 6 1 2x27 1 8 923325 227 assem 27 14 s 8x9 1 4 923324 236 assem 36 14 s 10 1 4x9 1 4 Order from your A P distributor today Our AP PRODUCTS distributor list is growing INCORPORATED daily For the name of the Box 110 72 Corwin Drive distributor nearest you call Painesville Ohio 44077 Toll Free 800 321 9668 216 354 2101 TWX 810 425 2250 ELECTRONIC EXPERIMENTER S HANDBOOK Great Jumpers are here Se E State of the art 3 flat cable connector assemblies at affordable prices Great Jumpers come to you fully pre assembled and fully pre tested Cable strain reliefs are integral to the molded on connectors And we ve designed in complete line by line probeability with probe access ports behind each contact Our
164. ed 325 PR 2 For 2708 PROMS Wired 325 SW1 SCANNING WAND Optical bar code scanner for programs published in optic bar code Requires 12 V parallel interface mir verde one Tn EROS PEERS 125 AC 1 POWER CONTROLLER Allows TTL logic levels to turn 110 V a c powered devices on and off Opto isolated Has two 110 V a c outlets plus manual turn on switch Returns ze ro crossing signal to computer allowing power to be turned on at desired point in cycle for resistive or in d ctive loads INE s noue ed 50 MINITERM ASSOCIATES WORD PROCESSING KEYBOARD Ninety keys with tactile feedback 100 million oper ation guaranteed keyswitches Upper and lower case 12 function keys numeric pad four on off keys and auto repeat Wired in enclosure 235 MITS ALTAIR FLOPPY DISK SYSTEM Nonvolatile fast access memory stores over 300 000 bytes per disk 4k bits on each of 77 tracks Average read write time 400 msec data transfer rate 250k bits per second Disk controller consists of two PC boards that fit the Altair bus connects to the disk drive via a 37 pin connector The 88 DCDD consists of the disk controller and one disk drive Kit assembled se 1425 1715 88 DISC Additional disk drive in cabinet TIENI SUPR RC AS 1215 1355 ALTAIR MINIDISC Similar to above but uses smaller 5 in mini floppy disk up to 72k bytes per
165. ed character fonts available MICRO BUILDERS INK BURROUGHS FRIDEN TERMINAL INTERFACE Interface Burroughs Friden communications termi nals to Altair bus Parallel I O but simulates serial port with TBE and RDA flags replaces TTY with no software changes Interface is wire wrapped card with switch selectable port addressing and lower case lockout jumper selection or half or full duplex Draws about 0 5A from 8 V bus requires about 1 A 24 V additional for terminal mechanics Wired deb E A No E E 150 Power Supply 24 V 1 A power supply Wired 40 MICROGRAPHICS THE DETAILER Video display for alphanumerics 64 characters 16 lines uppercase and graphics Has character selective inverse video 64 programmable graphics characters Uu eost E erre 249 MICROLOGIC M705 RESTART CLOCK BOARD Automatically restarts computer at any desired memory address no restrictions to 4k or page boundaries after power failure if memory has bat tery back up automatically saves contents of regis ters until power returns Protects memory against random writes when bus voltage is low Real time clock generates interrupts under software control for clock reference or event timing Includes DIP socket and switch to replace front panel sense switches where necessary Wired only 100 M7121 0 BOARD For interfacing Digital Group Phi Deck cassette system to Altair bus computers also suitable for general purpose bidirect
166. ed off by capacitors C3 and C4 The output of the preamplifier is ap plied to C2 a high gain noninverting amplifier Associated with the amp lifier are a low pass filter 3 dB at 1 kHz made up of C6 and R11 and a high pass filter 3 dB at 200 Hz made up of C7 and R12 A second high pass filter Q4 further reduces low frequency components Sensitiv ity is set by R25 and the signal is ap plied to a gain of 30 noninverting am plifier C3 which also acts as a rec tifier integrator and meter amplifier Rectifier D7 is located in the feedback circuit to reduce the effects of the diode voltage drop to a few millivolts Transistor Q5 acts as a buffer between the integrator and the meter Overall muscle activity can be aver aged between 5 ms and 0 5 s depend ing on the setting of R26 The sensi tivity control R25 is calibrated when integration Is set at maximum Theoutput frequency of the voltage controlled oscillator C4 isa function of the voltage level applied to its input through R22 The timer is biased so that at a certain low voltage thresh 1978 Edition MUSCLE BIOFEEDBACK APPLICATIONS Feedback Technique for Deep Mus cle Helaxation Experiments have shown that zero firing of single motor units with EMG BFT can be achieved in less than twenty minutes Most sub jects report changes in body image Further work reveals that people can subjectively turn on and off selected single muscle motor units
167. eight devices in priority order vectoring each to appropriate instruction address also provides time controlled interrupts based on System clock or a c power line frequency Kit UO c uoc dee MH A t 138 185 88 AD DA Eight bit analog digital digital analog converter eight multiplexed input channels two output D A converters Wired 395 88 ADC 12 bit analog to digital input interface with eight channel multiplexed input for unipolar inputs 0 5 V 0 10 V direct input to buffer available for Tem Nm bipolar 5 V 10 V input Also provides vector in terrupt facility for reading at fixed real time inter WIS VV ING Cl see m cte e M eM tt 524 88 MUX 24 channel multiplexer replaces eight channel multiplexer of 88 ADC board MUX and ADC together occupy one slot Filtering and scale factoring independently adjustable for each chan nel or available with differential inputs for small sig nal applications Up to four MUX cards may be used with one ADC on special option permitting up to 96 input channels Wired oes See heredi 319 88 PCI Process control interface Eight relay out puts for device control eight opto isolator inputs plus handshake logic Status of all relays set at This is easy anyone can solder WITH KESTER SOLDER lt T tn m j j Te i WU il Handymen Hobbyists ae DO IT YOURSELFERS Let Kester Solder aid you in your home repa
168. en tional 6 3 volt 400 mA transformer which is mounted off the board If you elect to use a higher voltage transform er a suitable dropping resistor H1 must be placed in series between filter capacitor C2 and the input to the voltage regulator as shown in Fig 7 The origi nal Elf was battery powered Construction Elf Il is constructed on a double sided pc board such as that shown in Fig 8 along with the compo nent placement If desired the system may be wire wrapped using perforated board and wire wrap sockets and com ponent pins Observe the correct polarity when in stalling the electrolytic capacitors LED Q1 as well as the pin 1 identifiers on all the ICs Sockets are suggested for all IC s This is especially important for the two memory chips A and A2 so that they can be easily removed when ex panding the memory via the new bus The keypad switches are installed by 93 2 AVANTI HIGH PERFORMANCE C B ANTENNAS 40 CHANNEL ENGINEERED ASTRO PLANE CB Base Antenna Co inductive The omni directional CB antenna that radiates from the top for greater range and performance 4 46 db gain over isotropic stronger signal clearer reception No coils to burn or Short Vertical polarity Patent 3587109 Model AV 101 price 39 95 2 8x more power E R P Avanti CB base antennas from 20 50 to 404 00 RACER 27 CB Mobile Antenna Magnetic mount Easy to mount on roof or trunk
169. ength of shrinkable tubing Push it all the way down to ward the board and shrink it Pass the free end of the cable through its grommet lined hole from the inside of the body and Slip over it another 4 in length of shrinkable tubing Strip away 5 in of outer insulation and re move and discard 45 in of the braided shield Being careful to avoid heat damage to the cable s inner insula tion pre tin the braid on one side with solder Strip 3s in of insulation from a in length of stranded hookup wire and pre tin the exposed wires Then carefully tack solder the wire to the shield stub Slip the tubing down over the connection overlapping it by in and shrink it Strip away 4 in of insulation from the free ends of the inner conductor of the coax and the stranded wire Solder a red booted miniature alligator clip to the inner conductor and a black booted clip to the stranded wire Next make a 2 in slit lengthwise 1978 Edition which uses tiwo ICs i one end of a 4 in length of v2 In diameter shrinkable tubing Slip the tubing over the board slotted end toward the tip located on the foil side of the board Locate and mark the pos itions of the LED lenses Remove the tubing and punch or drill Ve in holes in the marked locations Note This tub ing will not be shrunk during final as sembly To assemble the probe slip the tub ing into the probe body and line up the two sets of holes Slide the board as
170. ent capa bilities This supply is also very well regulated is adjustable and will sup ply up to 50 volts at one ampere The lower limit of voltage output is approx imately 8 V This characteristic is in trinsic in the design No attempt was made to incorporate an adjust to zero output capability because of the added complexity and lack of need to operate very near zero The minimum output of the other two supplies is about 1 5 V This supply is handy for performing odd jobs in conjunction with the circuit under test such as powering a small motor heater etc or part of the circuit that requires higher power It can also be used as a battery charger at 24 or 36 volts All three supplies have adjustable current limiting circuits and output voltage limiting capability The cur rent limiting can prevent destructive conditions in case of accidental short ing or overloading of a circuit This feature also lends itself to operation of the supplies as constant current sources with the current level being adjustable over a wide range Over voltage limiting was added as a result of the destruction of IC s due to ad justment of previous supplies to too high a voltage level Each supply has its own meters for continuously monitoring its voltage and current output so there is no need 14 THREE WAY POWER SUPPLY Two 0 15 volts at 750 mA and one 50 volts at I ampere supplies have both voltage and current limiting BY J R
171. ependent of each other and of previ ous occurrences The rate of counting makes the selection process sufficiently random The pitching adjustment for Little Mi nor or Major League is made with R35 The charging time for C4 is adjustable from 0 05 second charging resistor 470 k to 0 275 second charging resis tor 2 47 meg Thus the time the home plate LED is lighted is 5 2 times longer in the Little League than it is in the Majors Potentiometer R35 is con tinuously variable so that adjustment to times between the indicated positions Is possible This potentiometer only ad ELECTRONIC EXPERIMENTER S HANDBOOK COMMON DRILL 6 HOLES 1716 DIA DO NOT DRILL 4 REMAINING PADS 4 E S5 6 BALL 2 GND RIGHT LEFT S6 Fig 4 Etching and drilling guide and parts placement for Batter s Box Note that switches are mounted on pc board CENTER BALL 3 PITCH Fig 5 Shown is switch wiring guide for Batter s Mound justs the on time for C4 generated fast balls slow balls still travel at the same speeds The league selection al lows everyone from small children to the super star to play the game and be challenged by it A simple but useful option is an audi ble hit indicator In Fig 2 C2 is an oscil lator operating at about 2 5 kHz Power is applied to the oscillator only when pin 3 of IC1 goes high Timer C1 is a one shot with an on time of about 4 sec ond When a hit occurs p
172. er case Greek characters text edit mode Comes with 2k 4k On board RAM expandable to 65k sockets for monitor ROM plus 3k PROM 2708 or 6k ROM 2316 2k assembler ROM available Maintenance contract available 020923 001 Baby 1 system with 2k RAM Wired CET TOU AA EAN E A E OMAR RA SAD tie Ua 850 020923 002 Same with 4k 1000 020923 003 Same with 4k RAM 9 in TV monitor cassette recorder 1200 020923 004 Same with 8k BASIC ROM and ROM card M Max rM 1450 190923 001 Expansion card with serial UO 250 130923 004 4k Static RAM add in am 205 020119 008 ROM card with 8k BASIC compatible with any 6502 system s sess 250 060419 001 Mini floppy drive with power supply and controlier ENS 750 0604 19 004 Same with dual drive with your business card or send 1 00 re fundable on Tst order LARGEST CATALOG IN ITS FIELD patalog Includes amp Mant t tudes News about amazing E amp earkrthroutnns in the M rer rocomptute t e 52 00 Discount Certif cate e Discour up to 90 U A Complete Computer System 289 s Fully Assembled Fully tested Ten day Money back Guarantee KIM 1 MOS Techno ogy Computer Module 1K RAM audio cassette interface 15 bidirec tional lO lines 24 key keyboard and six d git LED display System Power Supply 5V at 1 2A 12V at 0 1A with power I ne and switch Software System Executive Sample appli cation programs Documentation Visa amp Master Char
173. er makes an ideal form for winding sensing Coil L7 For dura bility however it should be made rigid by adding a 6 in by 3 in piece of in Bakelite or phenolic board as shown in Fig 5 The board that adds rigidity can be fastened with three sets of 6 machine hardware one set of which also anchors into place the U bracket required for fastening the sensing loop assembly to the handle of the metal locator Sensing loop L7 consists of 20 tightly wrapped turns of No 32 enameled wire around the rim of the freezer container lid Secure the turns with coil dope and a turn or two of electrical tape You can either bring the ends of L7 out to a phono jack mounted on the freezer container lid or solder the cable that interconnects loop and oscillator directly to the 44 Fig 2 Diagram shows how components ave laid c2 out on perforated phenolte board 1 Bi i a Fils a s A i ie a mss i j NER eS T OMON SI a loop s leads The connecting cable it self should not exceed 36 in in length and should be a low capacitance vari ety like the Belden No 8411 used for lapel microphone cables In Use To operate the metal locator tune your transistor receiver to a strong station in the middle of the AM band and slowly tune C2 back and forth A beat note will be heard when you cross the station tuned on the re ceiver Carefully adjust C2 until the beat note disappears or is as low as possible Do not forget
174. er with 1k 16 bit words of EPROM with TI BUG monitor 256 16 bit RAM expandable on board to 4k x 16 EPROM 512 x 16 bit RAM Par alle and serial RS 232 20 mA I O two pro grammable interval timers 15 external hardware in terrupts and blank board area and extra sockets for prototyping Will work with TI 990 4 prototyping sys tem Hexadecimal microterminal four slot chassis and other peripherals to come Requires power sup ply 5V 1 3 A 12V 0 2 A 12 V ta 0 3 A Wired s c onte M LC 450 VECTOR GRAPHIC VECTOR 1 8080 MPU 18 slot computer with six connectors installed 20 A power supply whisper fan PROM RAM board with 1k RAM room for 2k 1702A ROM 512 byte monitor for use with Tarbell cassette and Altair IMSAI or Polymorphic I O boards Kit wired Mau word re M c 619 849 Without PROM RAM Sen 519 619 Without CPU UR ess ss 499 699 Without CPU or PROM RAM aan 349 499 WESTERN DATA SYSTEMS DATA HANDLER 6502 MPU computer with variable speed clock 2400 baud cassette interface 1k on board RAM one parallel I O port hex keypad entry with binary display I O control switches solder pads provided 108 for connection to a single Altair bus peripheral board or motherboard for multiple board use In wood case Requires power supply under 2 A t 5 V Available as unpopulated bare bones kit kit with all components assembled 80 200 235 Metal Case Black anodized with tr
175. ernaventotee Robert C Frosthoim and Roger Lundegard An electronic game project to challenge your reflexes TWO SINGLE IC AM RECEIVER PROJECTS 1 THE SIMPLEST AM WWYV RECEIVER ccccccc ccccecssocceccccccocceonsoreeccoccccctonsecescaccccncconsesersczccceeees Carl C Drumeller 2 AN FAA WEATHER RECEIVER ccccccssssscssssssesscccsccccsscesscccessesssonccssccnccesscsscocsccecssececcseees Michael S Robbins LOW COST REMOTE CONTROL OF APPLIANCES AND LIGHTS eren tente ne cens George A Ellson BUILD A SINE WAVE INVERTER rin col eo Cul pUE C abl E F PEO YU Th CF ex YO bI E cona s rh ERO MP Da vert Un bru eh Ya ne bee NA Martin Meyer SIMPLE TESTERS FROM JUNKBOX PARTS ccccccocccssoccocscoccosssessecseccccconsesssensececcesecscccccesarceceass Joseph E Taylor SOLID STATE PHOTOCELLS FOR HOBBYISTS 0 cccccccccccccccccesssssseseccscccccecesssceeseccusececccesccees L George Lawrence How light sensitive semiconductors are used in practical circuits IC SPEED CONTROLLER FOR HO MODEL RAILROADS eeeeeeeeeee err eene esee eae see esse see tese s aas Robert D Pascoe BUILD THE TRANSISTOR IDENTOMETER cccccccccceccccccscsssccerseccocosscsocsaccaccesccncccsecsscascessocccsececcessecs John T Bailey HOME FREEZER THAW ALARM e ceeerr ea icem e tote ecaocace Ces ter teeo stove cesare e devise Ser eF esed Dev nEEeee net Franklin C Willoughby HOME COMPUTER BASICS aou nie rta Na c IER HR TEES
176. ers in the series Working with the 565 The 565 PLL is the only member of its family that is not internally stabilized with a zener diode Therefore a well regulated supply or a zener diode should be used to keep the power sta ble Suppose you wantto use a 565asan SCA background music decoder A suggested circuit is shown in Fig 3 The SCA signal is 14 kHz FM on a 67 kHz subcarrier Note that a single ended power supply is used and the resistor network made up of R3 through R6isused to bias the inputs at 3 2 volts Thus only one comparator input pin 2 is used for the signal The two input capacitors C2 and C3 and resistor R2 act as a high pass filter to remove the lower frequency stereo subcarrier from the SCA input Capacitor C7 and resistor H7 deter mine the operating frequency of the internal vco by the expression 1 2 4R71C1 Since we know that the vco should operate at the SCA fre quency of 67 kHz and we would like R1 to be about 5000 ohms we can 10V R3 IOK iK RI 10K c2 C3 510 510 pF pF 8 IO weuro 5 The demodulated output pin 7 is passed through a three stage low pass filter C5 to C7 and R7 to R9 to provide the necessary de emphasis and attenuate the high frequency noise that often accompanies the SCA transmission The demodulated out put signal is approximately 5C mV and the frequency response extends to 7 kHz The locking range is determined from 8F V which comes out
177. erter not supplied Total price for the kit 398 00 j Send me the Fall 77 Catalog enclose 1 m would like to order directly from this advertisement Please allow up to 60 days for delivery WAME 0 ae EY ADDRESS e m E Es ____STATE_ ZIP To Order Payment by BAC Visa MC Money Order Credit Card Account Interbank 4 Master Charge __ Model 500 Boards 298 00 Challenger IIP 598 00 i _ sd Super Kit o 398 00 7 Ohio Residents add 4 sales tax es TOTAL CHARGED OR ENCLOSED Order directly from Ohio Scientific 11679 Hayden St Hiram Ohio 44234 or your local OSI dealer All orders shipped insured UPS unless otherwise requested 11679 Hayden Hiram Ohio 44234 6 CIRCLE NO 19 ON FREE INFORMATION CARD ELECTRONIC EXPERIMENTER S HANDBOOK Build A game of skill and quick reactions BY JAMES J BARBARELLO HE Batter Up electronic game de scribed here simulates the game of baseball It incorporates sufficient varia tions in pitching speed and changeups to play the game without outgrowing it The strategy is to outfox your opponent by determining which pitch is his weak ness The circuit makes use of the familiar 555 IC timer which works properly with 1978 Edition a power supply of from 5 to 15 V d c Low current drain due in part to LED blanking allows standard type
178. es with typical vco operation of 15 MHz and a maximum of 30 MHz Above 15 MHz its opera Fig 1 Four basic elements of a phase locked loop LOW PASS FILTER TIMING TIMING CAPACITOR RESISTOR ELECTRONIC EXPERIMENTER S HANDBOOK OUTPUT Ies RANGE Fig 2 Upper trace shows beat between vco and input Lower trace is the lock range tion becomes critical and great careis needed to get them to perform prop erly Its input sensitivity is very good the device can lock on to sign als of 100 to 200 microvolts The 561 is a duplicate of the 560 but it has an added product detector for synchro nous demodulation The 565 has an excepticnal lock range typically 60 however its input sensitivity is only fair 1 millivolt for lock The 565 has one added advantage over the high frequency units its vco is tuned with an RC network and frequency is directly proportional to the change in the resistance This permits tuning over a 10 to 1 frequency range using a potentiometer The 567 is primarily a narrow band filter its interesting feature is a built in synchronous switch which turns on when the unit goes into lock The switch is able to handle up to 100 mA and can be used to turn on an SCR a relay or a lamp for indication of the lock condition Another feature of the 567 is its low power supply voltage 4 volts minimum making it ideal for battery operation However it is less input sensitive than the oth
179. es in the same way as that for player A If 2 o cagesee 00 o o E B ong p E eacceas o9 99 o TILLIT LLLI e o gl o 9o 80009808 386608 oo oo Do o o both players press their buttons at the same time the signals cancel each other After playing the game for some time the players reflexes will appear to have improved to the point where the game becomes a standoff In this event reduce the values of R4 and R6 to shortent2and t3 Resistors R26 and R31 should be reduced by the same percentage as R4 and R6 to reduce the possibility of confusion in the AND gates since the pulses at X and Y will be much shorter When one player has moved the lit LED to his end LED11 islit and diodes Df and D2 prevent any further action until the START button is operated The game can be made more excit ing by adding a circuit to provide an audible indication of which player has won The circuit is shown in Fig 4 Tone bursts are generated by C8 and ICJ Each half of C8 acts as a on2 shot which determines how long the as sociated half of C9 is activated The two halves of C9 are oscillators with outputs of different frequencies When a player wins a game the signal at A or B causes the appropriate cir cuit to provide a sound through the loudspeaker The simple power supply shown in Fig 5 can be used for the Tug of War 59 J Q4 oF h TPE Fiat Pg enn R Hg is mr fairey ey mag LESPE
180. es power supply moth erboard real time clock vectored interrupt ROM 5e cd system monitor 16k RAM serial port RS 232 or current loop motherboard 300 2400 baud cas 99 sette interface 16 line x 64 character video display output full ASCII plus 48 x 128 graphics modes keyboard in separate housing 9 in CRT monitor and system cabinet plus BASIC clock and PLOT functions Wide range of peripherals and software available Wired only With 16k 24k 32k memory uM M IUE 2300 2675 2875 CROMEMCO Z 1 Z BO MPU computer with front panel controls and indicators Uses selected high speed 2 80 MPU i af d i T A EA deje Mel ande sait seat i i aia i d f r a ame mom dfi m ip ditia e uC ed sanakin a dpi e cbr teta petat neirt a chip 21 slot motherboard PROM programmer with 8k capacity 2708 32 A power supply 8k RAM memory RS 232 serial interface 1k monitor Wired nc ce eee te A ae ala Lan eae A a 2495 zZ 2 Similar but without front panel Power on jump cir cuitry begins automatic program execution when power is turned on Rack mount design cabinet op tional with 60 A power supply for cards and other peripherals special 21 slot Blitz Bus motherboard design to reduce ground current noise Kit wired Mond res M LEE 595 995 CYBERSYSTEMS MICROCYBER 1000 6502 MPU system with built in hexadecimal key board and display 2k ROM operating system 1k
181. ess 6800 MPU chip 98 AM6G800PC PC board and documentation only 40 MULLEN EXTENDER BOARD Raises Altair bus boards above others in chassis for easier in circuit testing Includes TTL logic probe in dicating low and high level logic and pulses jump er links in power lines for current measurement and fusing of board under test Kit only 35 OPTO ISOLATOR RELAY CONTROL BOARD Interface board for device control Has eight reed relays rated 10 VA 20 200 V controllable by eight bit computer command eight opto isolators for feedback handshake I O port address switch selectable Kit Only suse adotta ee 117 NATIONAL MULTIPLEX 2510 R BOOTSTRAP ELIMINATOR Combination ROM monitor cassette and serial O board Connects terminal 20 mA RS 232 or TTL one or two digital or audio cassette units all neces sary routines in high speed fuse link ROMs includ ing tape start stop for audio cassette plus rewind and fast forward for digital tape units Includes word processing tape punching and reading rou tines Can be used for phase encoded Kansas 116 City MITS and IMSAI tapes Kit wired 160 190 PARASITIC CLOCK FIX KIT Temperature compensated non overlapping clock for Altair 8800 and 8800a ee 15 CONSTANT VOLTAGE KIT Constant voltage transformer high current rectifi ers and improved filtering to maintain Altair perfor mance with line voltage swings up
182. even deli cately controlling their firing patterns Paralyzed Muscles Retrained at Home People recovering from car diovascular accidents are often faced with the retraining of paralyzed limbs a long and tedious job Exper iments are revealing now that much of the work load can be taken off the pa tient and also speeded up if biofeed back techniques are applied An EMG monitor can sense minute muscle ac tivity and inform the patient of the ac tivities instantly Talking Muscles Help Scientists Design for Maximum Efficiency A group of researchers at Eastman Kodak Co known as the Human Fac tors Group is looking into the activity of muscles in industry Using the re sults of EMG data and performance tasks they are able to design steps for a job to provide the least muscle dis comfort while obtaining maximum productivity of body movements old the oscillator automatically shuts off The threshold is determined by the gain ofthe circuitand the value of R24 The turn on threshold is approxi mately 2 5 microvolts at the skin elec trodes with the sensitivity control set to maximum Reducing the sensitivity raises the threshold point The threshold was selected to make changes in muscle tension more ap Fig d The EMG feedback loop SKIN f ELECTRODES COMMON RECT AND INTEGRATOR EMG Signals Give Hams a Third Hand Many who are physically hand icapped are interested in amateur radio as
183. exclusive The only solderless breadboard sockets Sockets lock together snap apart With full fan out capabilities for micro a 2 sao ean e s to handle any circuit processors and other larger 0 6 DIP s m o AS GO a6 E e Snap together in a domino pattern Arrange EXPERIMENTOR CUTE Y TEN S Far ae FATS sockets to suit your circuit Expand or contract at will Sere ET Simple Mounting Vinyl insulated backing lets you mount EXPER Number in parentheses refers to total number of te points IMENTOR sockets anywhere without shorting Mount to any flat surface with 4 40 flat head screws or 6 32F self tapping screws for CALL OR WRITE behind the panel mounting FOR FULL LINE CATALOG e Accepts All Standard Components Sockets conform to 0 1 grid and are DIP compatible Accepts IC s diodes resistors capacitors AND THE NAME transistors etc OF YOUR CSC DEALER Use 22 30 solid AWG wire interconnections US Pat No D235 554 All Prices Shown are Manufacturer s Recommended List Prices and Specifications Subject to Change Without Notice 12 ELECTRONIC EXPERIMENTER S HANDBOOK TO READ THI Proto Boards with Built In Regulated Power Supplies For extra convenience and breadboarding speed Prata Board mo 203 PB 203 Same capacity and layout as PB 103 plus short proof fused 5VDC 1A regulated power supply Ripple and noise area low 10mV at 0 5A Has on off toggle switch and pilot light plus four
184. ey are mounted visible Needless to say a device that is a light source itself a lamp is infinitely more preferable and safer than a pas sive reflector Therefore we present in these pages two different types of lights that can make your night biking safer One is a headlight that com bines the advantages of both batteries and a generator The other is an attention getting blinking taillight amp PARTS LIST Bi 96 voit lantern battery C1 100 LF 25 volt electrolytic capacitor D1 D2 IN4002 diode 11 12 6 volt 0 l ampere bicycle light Q1 2N2102 transistor Q2 2N 3055 transistor Q3 2N2905 transistor R1 100 ohm 2 watt resistor R2 20 000 ohm 2 watt resistor S1 Spst switch Misc Suitable enclosure for circuit per forated board and push in solder clips suitable lensed housings for I1 and 12 hookup wire solder machine hard ware etc 1978 Edition PROJECTS ALWAYS ON BIKE LIGHTS BY CHARLES R CLINKENBEARD RADITIONALLY you powered the lights on your bike with bat teries or you opted for generator power Batteries deliver the same amount of power to the lamp whether the bike is moving or at a standstill However they are quickly depleted of their charges requiring periodic re placement Generators on the other hand hardly ever need replacement Their disadvantage is that variable power is delivered to the lamp de pending on the speed at which the
185. f microprocessors Read puter components This has encouraged the devel BYTE The Small Systems Journal that tells you opment of new low cost peripherals resulting in more everything you want to know about personal com hardware and software more applications than you puters including how to construct and program could imagine more opportunities for vou BYTE brings pour own computer over 30 000 BYTE readers itall to you Every issue is packed with stimulating and ave already built or bought their own systems timely articles by professionals computer scientists and and half of these have 8K bytes or more serious amateurs You ll find our tutorials on hardware and software BYTE editorials explore the fun of using and applying invaluable reading also our reports on home ap computers toward personally interesting problems such plications and evaluative reviews based on ex aselectronic music video games and control of systems periences with home computer products for alarms to private information systems practical affordable Large scale integration has Home computers Subscribe now to BYTE The Small Systems Journal mammam mum mum mu 04 09m Rm nd ee I Read your first copy of BYTE Subscriptions Dept P O Box 361 Arlington Mass 02174 U S A r BYTE if it s everything you 38Z Please enter my subscription for expected honor our in O One year U S 12 Two years U S 22 C Three years U S
186. for car van or truck no holes to dnll fast removal for hide away r car washing Strong magnet assures position Mylar pad guards yehicte finish Hermi coil Hermetically sealed coil L A special molding process provides a weather proof coil i environment Helps maintain the 1 characteristic antenna Impedance dii even in damp or salt water atmosphere Hermi coil also helps eliminate internal surface leakage Ribbed base Provides along leakage path used in high voltage insulators spark plugs etc La Specifications Electrical wave length amp Unity gain 27 MHz amp VSWH 131 orbetter Coil shunt fed hermicoil MODEL AV 727 Mobile Antenna System with 48 whip 17 coaxial cable with magnetic mount 40 channel 32 95 Avanti makes a complete line of high performance mobile CB antenna systems from 11 95 to 72 50 FREE 24 PAGE CATALOG avanti Avanti Research amp Development Inc Estabhshed 1964 340 Stewart Ave Addison IL 60101 USA creatars of the famous Copynght 1977 All rights reserved 94 CIRCLE NO 2 ON FREE INFORMATION CARD XTAL 3 58MHz R32 4701 R3I 4701 TO A6 PINI CLOCK IOK 5V T CIO 3530pF A RUN TPA TPB INT DMA OUT Sco SCI D DI D2 D3 D4 DS D6 D7 VIDEO OUT Fig 2 The crystal controlled clock A uses a conventional color TV erystal and drives the one chip graphies interface B
187. fore you begin digging e ELECTRONIC EXPERIMENTER S HANDBOOK BY JOHN F HOLLABAUGH onm ranges chews 500 uF to 100 volts full scale NT Doubles as ohmmeter down to 0 02 ohm Use fo measure current down to I0 nA Costs under 20 OW you can have a volt meter that measures from 500 microvolts to 100 volts full scale in 12 overlapping ranges costing less than 20 Designed for use on circuits where a little voltage makes a big dif ference the sensitive Minivolter is ideal for use on solid state equip ment In these low voltage circuits many conventional meters can t be used because of their relatively low input resistance The input resistance of the Minivolter is one megohm per volt drawing a current of one pA The Minivolter can also measure ac voltages if a 1 2 multiplier is used And it will serve to indicate r f levels in orienting TV antennas and to peak the low level stages of transmitters How It Works As shown in Fig 1 op amp C1 is used as a voltage fol lower and C2 as a linear rectifier Any voltage applied to the input of C2 is multiplied by the gain of the op amp and inverted The difference between the input pin 2 and the output pin 6 is high enough that the fixed voltage drop across D7 and D2 can be hidden by the drop across the series portion of R15 So the difference can be con sidered not to exist Also the diode barrier potential 0 7 volt does not place a lower limit
188. g the components be sure they are properly oriented with regard to ter minals and polarities Don t forget the single jumper on the component side Note that some pads onthe foil pattern have numbers Corresponding to those on the schematic The pc board and the two batteries preferably alkaline are installed in a Suitable metal enclosure Metal is used to keep 60 Hz interference to a minimum Mount the components on the front panel as shown in the photo graph The audio output jack is mounted on one sideofthe enclosure The SENSITIVITY control is marked for 10 uV in the full counterclockwise position 500 uV at the center and 10 WV at the other end Mark the 29 30 Cl e lpr ACTIVE REF D SI 3 Q Q ELECTRODES C2 lpr VI Q4 2N3565 Qi 2N3565 R3 47K R5 47K R2 IK R6 100K VI 5i 7 IN400 C8 OlpF vi RI5 OK oon RIT ERR tog 130K A RIB AUDI nop OUT 4 7K a fa 220n 2 7 P IC4 cco 555 3 be S NA M VI Fig 2 Sehematic of monitor circuit PARTS LIST B1 B2 9 volt battery C1 C2 0 uF 10 Mylar capacitor C3 C4 0 001 uF 10 Mylar capacitor CS5 C11 10 uF 10 V electrolytic capacitor C6 100 pF 10 silver mica capacitor C7 I1 uF 10 V electrolytic capacitor C8 to Ct0 0 0i uF 10 Mylar capacitor C12 C13 50 uF 10 V capacitor C 14 C 16 0 1 uF 10 Mylar capacitor C15 047 uF 10 Mylar capacitor D1 IN 4001 diode IC to IC3
189. ge accepted NEWMAN COMPUTER EXCHANGE 1250 N Main St Ann Arbor Mi 48104 313 994 3200 Dept EH CIRCLE NO 15 ON FREE INFORMATION CARD 107 TECHNICAL DESIGN LABS XITAN ALPHA 1 Z 80 MPU system with two serial I O ports RS 232 or 20 mA 1200 baud audio cassette interface 2k RAM 2k ROM monitor 8 A power supply operates on 110 120 V or 220 240 V a c power on clear and reset In cabinet with eight card slots six avail able for expansion front panel reset switch rear panel power switch to avoid accidental power off Kit wired 0 E ee ors soot 769 1039 XITAN ALPHA 2 As above plus one 16k memory board leaves five slots for system expansion for 18k total RAM one parallel I O port software including 8k BASIC Text Output Processor Zapple Text Editor and Relocat ing Macro Assembler Kit wired 1369 1749 TECHNICO SUPER STARTER SYSTEM Based on TI9900 16 bit MPU single board com puter with 1k PROM 512 bytes RAM EPROM pro grammer serial RS 232 20 mA VO on board Ex pandabie to 2k RAM 2k PROM 2k EPROM on board to 65k total memory with expansion boards Peripheral boards available include 32k byte memo ry expansion board video audio cassette interface keyboards floppy disk power supply interface board chassis with limited or full front panel CRT printers KIEPWITGO erc errare 299 399 TEXAS INSTRUMENTS TM990 100M Based on TMS9900 16 bit MPU Single board comput
190. ght reflector 1978 Edition nearest the front of the engine The number one cylinder on a V8 engineis also nearest the front but it could be either on the left or the right With the engine shut off remove the ignition lead to the number one cylinder and connect the timing light s plug lead to the plug Replace the ignition wire Before starting the engine it is ad visable to clean the flywheel and paint a thin white line over the timing mark so thatitis readily visible Then refer to the decal located in the front of the engine compartment of late model cars to determine the calibration of the timing scale and proper ignition timing specifications Remove the rubber hose connected to the vacuum diaphragm of the dis tributor and plug the hose opening with a pencil This disables the au tomatic vacuum advance built into the distributor Timing of an engine is al ways adjusted with the vacuum ad vance disabled If you neglect to do this you will set the timing incorrectly and the engine will not operate prop erly Connect the remaining two timing light cables to the car s battery ob serving the proper polarity Start the engine The light should now be flash ingatarate of 4to 5 times per second Aim the timing light at the flywheel to locate the timing mark The mark should appear to be stationary If tim ing is not correct loosen the bolt that clamps the distributor assembly to the engine and rotate the distribut
191. gnetics LED1 LED11 Green MV5253 Monsanto or similar LED to LEDIO Red MV5053 Monsanto or similar R 20 000 ohm 44 watt 10 resistor R2 680 000 ohm l watt 10 resistor R3 430 ohm A watt 10 resistor R4 R6 200 000 ohm V watt 10 resistor R5 R7 RIO R11 R22 R23 R27 R32 R34 2200 ohm watt t0 resistor R8 390 000 ohm V watt 10 resistor R9 R25 R30 22 000 ohm watt 10 re sistor R2 to R21 620 ohm watt 10 resistor R24 R29 2700 ohm V watt 10 resistor R26 R31 R38 R40 2000 ohm 4 watt 10 resistor R28 R33 510 ohm 44 watt 10 resistor R35 R36 130 000 ohm watt 10 resis tor R37 75 000 ohm V watt 10 resistor R39 1 20 000 ohm V4 watt 10 resistor Si S2 S3 Spst temporary contact pushbut ton switch Spkr 8 ohm speaker Ti 6 3 volt filament transformer Triad F 14X or similar Misc Suitable Cabinet line cord rubber grommets 11 press type mounting hard ware IC sockets 9 clip on heat sink for IC10 solder wire etc Note The following are available from Four Seasons Corporation P O Box 24 Los AI tos CA 94022 C package TW 204 con taining CI through ICIO for 19 75 etched and drilled pc board TW202 for 12 95 walnut case with metal top plate screened and drilled TW206 for 16 95 California residents add sales tax All prices include shipping in U S only 97 that this oscillator sinks current LEDI
192. gonal screen Front panel in cludes brightness focus on off contrast vertical hold size horizontal size reduce size Rear apron has horizontal size two video inputs int ext sync two ext Sync inputs 75 ohm termination Bandwidth to 15 MHz Linearity better than 296 overall Resolu tion greater than 1000 lines in central 8096 of screen s D T NE 325 HEATH H9 CRT TERMINAL Displays 12 lines of 80 characters on 12 in screen formattable to four columns of 12 lines x 20 charac ters cursor control batch transmit plot mode 110 9600 baud serial RS 232 20 mA and TTL in MONACO WI eerie Ie oes 530 H10 PAPER TAPE READER PUNCH Uses standard 1 in wide paper tape roll or fanfold reads at 50 char sec punches at 10 char sec punch and reader circuits are independent and may be operated simultaneously copy mode fortape du plication power supply parallel TTL interface Kit Ter nU mor Fe 350 ICOM FRUGAL FLOPPY Single drive diskette system with controller 256k byte IBM 3740 format less power supply cabinet and interface see interfaces below Assembled eee ce fe t t Rs saga 1195 Additional dive eerie trm eu exe CERE ERSTE 665 F03711 Similar in cabinet with power supply and room for second drive eee sienne 2350 Second drive for above sessses eee 710 100 interface for above systems Wired 300 MICROFLOPPY 73k byte single drive mini floppy system with con tr
193. h a motor ACH dH MI R26 1978 Edition unit and each motor unit may drive many hundreds of muscle cells For medium tension with Ag Ag Cl skin electrodes the EMG energy isata frequency between 200 and 2000 Hz and an amplitude between 500 uV and 1 mV It is noise like in appearance However at low tension levels indi vidual motor units may be differen tiated with pulse rates of 25 to 100 pps Amplitudes are between 5 and 25 yV depending on the physical distance be tween the motor units and the skin electrode c7 mena 4 Selon 7 ce ae d RI R2 R4 R3 c5 R20 n C4 C3 C8 E I T RRE cl2 TET BRACKET MOUNTING R25 CONNECTORS INTEGRATION control 5 ms on full CCW 250 ms at the center and 0 5 s for full CW Circuit Checkout and Use With fresh batteries installed connect both live inputs across a resistance of 1000 to 5000 ohms and insert an ear phone in J1 With the MODE Switch ON REF and SENSITIVITY and INTEGRATION controls maximum clockwise turn on the monitor The meter indication should be between 1 5 and 1 4 of full scale indicating the maximum noise being generated in the circuit There may be a slight delay about half a second before the meter deflects as the input stage stabilizes Put the MODE Switch on ACTIVE and note that the meter indication rises as the added noise of the resistor comes into play Note also that the vco r
194. h power on start to any 1k address boundary Kit wired MEE EEUU EN SOMMER t 89 129 FDI Minifloppy Interface kit for up to three drives with bootstrap ROM Kit wired 260 329 BKPL Eight slot Altair bus motherboard 35 BKPL E Same with edge connectors wired 109 VDRK Card rack and BKPL E Designed for card oe Cah a rad E MEE RE TAI 160 MITS MEMORIES 88 AMCS 4k static RAM Kit wired 167 310 88 S4K Synchronous 4k board relies solely on CPU for timing signals to avoid wait states Access time 200 300 nsec Kit wired 155 255 88 16MCS 16k static memory board 765 945 88 PMS PROM memory Card holds up to 2k bytes in 4702 1702A PROMESA S er Ae 85 125 INTERFACES 88 2SIO Serial interface board for two VO ports one port supplied each user selectable for 20 mA or RS 232 110 9600 baud Kit wired 150 185 SP Second serial port for above 38 50 88 4PIO Parallel I O board for up to four O ports one supplied 16 data lines per port allow each to be used for one I O two input e g reader or two output e g printer devices Kit wired 105 130 PP Additional parallel ports for above 43 55 88 ACR Audio cassette interface compatible with Altair software 300 baud Kit wired 124 148 88 VI RTC Vector interrupt real time clock Accepts interrupts from up to
195. he correct terminals than to start over or modify the pc board The terminals of S2 must be modified as shown in Fig 3 so that the switch will fit the pc board as shown in Fig 2 Now you are ready to assemble the Circuit on the main board as shown in Fig 2 The front panel is marked as shown in the photograph with the six switch positions identified Install SO and mount the LED s in small rubber grommets properly identified TI PRIMARY a ADDED SECONDARY 46T 34 ENAMEL CLIP OFF BEFORE AFTER SWITCH LUG DETAIL Fig 3 Add a winding and fermindls to the transformer aud alter switch lugs as shown Then mount the switch on the front panel Connect the larger board to it with spacers Note that the large board has a small spacer supporting it from the hole drilled near the center of the rotary switch board Drill three small holes for the colored test leads and put grommets in the holes The leads are terminated with color coded insulated alligator clips From the top of the panel the lowest test lead green is on a line from the emitter terminal on SO7 the center lead yellow is the base and the upper lead red is the collector Operation Connect the three color coded test leads to the un Known transistor in any order turn on the power and rotate S7 until one of the LED s illuminates Make sure that this only occurs at one position The position of the switch will then identify the
196. he same fre quency as the input The circuit is then locked so that the loop frequency varies exactly with the input fre quency Thus the loop has three states free running Capture and locked or tracking The capture state is highly complex Interestingly the capture range frequency band above and below the vco center frequency is not as wide as the locking range A closer look at the capture state will provide an explanation Figure 2 shows the waveform of the voltage at the output of the error correction am plifier As capture starts a small sine wave appears This is the beat be tween the vco and the input signal Note that the negative half of the waveform is slightly larger than the positive half Thisisthe dc component of the beat which drives the vco to ward lock Each successive cycle causes the vco to move closer to the input signal There are two results of this action which help the vco to lock First the closer the vco approaches the input signal the lower the beat frequency This allows the low pass filter to pass more of the beat frequency to the vco with a correspondingly larger portion of the dc component The vco is now skipping twosteps toward lock and one step back At the same time the closer the vco nears lock the longer it wants to stay there and the more reluctant it is to move away This extends the negative half of the cycle reduces the positive half and increases the dc componen
197. hen feed inverter buffer transistors which in turn will power the display s segments The truth table with the 7490 s DCBA output lines feeding the 8223 s AA A A address lines respectively would be A A A A A B B B E I D c w 050000000 g O0 00000 Oo 00 0010 o o O o OP X X X X X X X OKO OK Ow er OO O O OO o o 0c00 0 0 0 O O oO 2 m as OnO O O a O a l l O 2 2 C Q ooo 5QtnK o0oJjg X X X X X X X XX ox The DCBA in the heading represents the outputs from the 7490 while the gfedcba represents the display seg ments controlled The X s are don t care states since there is no input to the input nor output termi nation for the B output lines of the 8223 PROM 1978 Edition SI PUSH TO BURN 12 5V 5V Fig 2 In this programming setup both power supplies must be regulated Once PROM is programmed its memory ean be checked as described in the fet this one not so readily available to experimenters is the Nitron Com panys NC7010 EAROM This device can be erased electrically in one second lt can be erased and repro grammed up to a million times The NC7010 is organized as 512 words of two bits per word How to Program a PROM The 8223 PROM used in the applications described is shipped with all of its outputs at a logic O level This means that all of its on chip fuses are intact If a
198. her drills wheels and burrs to 44 shank diameter Kit includes 4 collets No 6275 Drill with 110V transformer Mo 6280 Drill with FA lighter plug amp CLIPPER CORPORATION ORIGINATORS OF PRACTICAL CORDLESS SOLDERING 2902 Locust Street Sterling Illinois 61081 815 625 6525 CIRCLE NO 25 ON FREE INFORMATION CARD WAHL Includes Functional Tilt Stand NEW EKO 270 3 DIGIT DMM KIT ONLY 79 The first ard only lab accuracy por table DMM Kit featuring MOS LSI IC economy and reliability Mea sures DC AC Volts Kilohms DC AC milliamps in 21 ranges Polarity indicators and overload protection are provided and 0 5 inch LED dis plays give easiest to read digital readout to 1999 The 270 features a basic 0 5 DC accuracy 10 Meg ohm input impedance low voltage drop in all current ranges and auto matically flashing overrange indi cator Assembled 109 95 FREE 78 EICO CATALOG Check reader service card or send 75 for first class mail See your local EICO Dealer or call 212 272 1134 9 00 a m 5 00 p m EST Major credit cards accepted p o EICO 283 Malta St Brooklyn N Y 11207 CIRCLE NO 8 ON FREE INFORMATION CARD 105 hex display of address and data audio cassette in terface 15 I O lines interval timer under software control Can be used as stand alone microcomputer requires 5 V e 1 2 A 12 V 100 mA or expand ed with modules below Assembled 245 KIM 2 4k static
199. hich case it is called a bipolar ROM It can also be made from metal oxide semicon ductor devices which makes it a MOS ROM Whichever type it is the FOM is a digital device that remem bers information on the standard bi nary format of 1 s and O s The logic levels remembered by the bipolar 20 ROM are the same as those used in TTL circuits whereas the levels re membered by the MOS ROM are de termined by the supply voltage re quired by the device itself Organization An important charac teristic of the ROM is its organization The ROM remembers quantities of bi nary bits that are organized into words Each word has a certain number of bits For example one type DECODER LOGIC GATES ADDRESS LINES ONE OF 256 CELLS Fig 1 Partia diagram shows only two of 258 memory cells available iv a 256 bit ROM BY ROBERT D PASCOE of ROM can remember 256 bits of in formation organized into 32 words of eight bits apiece 32 words x 8 bits 256 bits Some of the more commonly avail able ROM s can remember 256 1024 2048 or 4096 bits in a single IC chip With the various types of ROMS the manufacturer determines how the total number of bits is organized in the chip The organization of the bits deter 1I Bo Bj B2 B3 B4 85 Bg B7 OUTPUT LINES ELECTRONIC EXPERIMENTER S HANDBOOK SOME APPLICATIONS FOR PROM s Tere are countless applications for the ROM Some of the more traditio
200. housed in a Sturdy metal container ELECTRONIC EXPERIMENTER S HANDBOOK ate Re c f Speed ech ra de Xp Ere na Py ITH A PAIR of integrated circuit operational amplifiers and a handful of parts you can build a precision speed controller for HO gauge model railroads at minimal cost The solid state controller fea tures forward reverse stop in crease speed and decrease speed Switches for full control flexibility In addition optional lighted pushbutton switches can be used to provide a vis 1978 Edition Model Railroads Precision low cost device provides full control flexibility and simple speed indication option ual indication of how fast the train is moving on its tracks The faster the train moves the brighter the light from the lamps About the Circuit Operational am plifier C7 in conjunction with transis tors Q1 and Q2 see schematic dia gram forms a voltage regulator cir cuit The output voltage from inis cir cuitis determined by the voltage at the BY ROBERT D PASCOE wiper at potentiometer R2 and the dc voltage across capacitor C3 Op amp iC2 is connected in a voltage follower configuration The dc voltage across C3 the reference for the regulator isa product of the time a constant current is pumped into the capacitor The two current pumps in this system are made up of the Q3 and Q4 circuits with Q3 the negative and Q4 the posi tive pump 75 Eo Uer capere ea
201. ided they are evenly spaced e ELECTRONIC EXPERIMENTER S HANOBOOK FREE EATHKIT CATALOG a de ih a The world s largest catalog of easy to build money saving electronic kits now featuring our entire line Ves of exciting new Heathkit personal and hobby computer systems Self Instructional Electronics Courses e Color TV and Hi Fi Components e Experimenter Breadboard e Electronic Clocks and Weather Instruments e High Performance Frequency Counters e Amateur Radio Equipment e VTVM s VOM s and Oscilloscopes e Nearly 400 kits for the Electronic Hobbyist Heath Ccmpany Dept 110 340 Benton Harbor Michigan 49022 Every Heathkit product comes with a fully illustrated step by step instruction manual that tells you everything you need to know to make kitbuilding fun and easy Thousands of people have discovered the satisfaction and savings of handcrafting a fine piece of electronics equipment You can build it better let us show you how Schlumberger Please rush me my FREE Heathkit Catalog am not on your mailing list NAME aam ADDRESS mum x RH R Send for your FREE Catalog today Heath Company Dept 110 340 Benton Harbor Michigan 49022 CITY ncc STATE CL 636A ZIP EE NE NE NE NEN NE NE NE NE EN DNE DE DE DE NE DE DE UN CIRCLE NO 5 ON FREE INFORMATION CARD qn baa we eee m dd 1978 Edition WI x 55 Mum Tm rr erre
202. iety of control applications such as a security system electronic games time delay control sequential lighting tem perature sensing and so on The basic computer COSMAC ELF was originally introduced as a perforated board project last year in POPULAR ELECTRONICS followed by a series of articles that introduced new features Elf II presented here incorpo rates all these upgraded features plus new ones as follows Double sided PC board Hexadecimal keypad with associated logic An 86 line bus for system expansion Video graphics Seven segment LED readouts 256 bytes of RAM A c operation The Basic Elf The basic computer circuit shown in Fig 1 and the graphics interface shown in Fig 2 are essentially the same as the original EIf s 92 PERSONAL MICROCOMPUTER Whereas the original Elf used a pair of relatively expensive hexadecimal de coders latch readouts to monitor the data lines Elf II uses a pair of conven tional 7 segment LED displays to do the same thing Besides the saving in cost the only difference between the two ap proaches is that in the Elf I method lower case b and d are used instead of capital letters However these cannot be mistaken for any other alphanumeric character The new circuit is shown in Fig 3 Integrated circuits A8 and A12 accept the digital information from the data bus buffered by A7 and A11 and convert this data to drive the com mon cathode 7
203. igator or crocodile clips and the plug lead with a spring type plug to cable adapter Turn over the circuit board and carefully solder a 4 40 machine nut to the copper pads surrounding the mounting holes Make certain that the nuts are centered over the holes and that no solder flows into the threads ELECTRONIC EXPERIMENTER S HANOBOOK The flashtube mounts in the flashlight s reflector You can enlarge the standard lamp hole in the reflector with a rat tail file working carefully to avoid damaging the reflector or scratching its reflective coating The flashtube s fit should be reasonably close without binding Place the re flector assembly face down on a flat surface and insert the flashtube in the enlarged hole positioning it with its point against the glass lens and verti cal to the plane of the lens Run a bead of epoxy or Dow Corning Silastic cement between flashtube and reflec tor and allow the cement to set over night Be sure to maintain the flash tube vertical to the lens as the cement sets Fig 4 Once the cement has set you can complete final assembly Locate the negative woven electrode lead of the flashtube and connect it to the hole marked FT1 in the component placement guide in Fig 2 Then con nect the positive electrode lead it ex its the end of the flashtube opposite the negative electrode lead to the FT1 point on the board The only connection left to be made is the spark plug test lead
204. ilable for your favorite magazines Master Charge Interbank 4 numbers over your name Signature Print Name Address Chy Slate p Residents of Calif Col Fla Ith Mich Mo N Y State D C and Tex add applicable sales tax Ld 1978 ELECTRONIC EXPEPIMENTER S HANDBOOK is published annually by the Ziff Davis Publishing Company One Park Avenue New York N Y 10016 Also publishers of Stereo Review Popular Electronics Citizens Band Handbook Tape Recording and Buying Guide Stereo Di rectory and Buying Guide and Communications Handbook ELECTRONIC EXPERIMENTER S HANDBOOK SOLID STATE OMPONENTS CHART PLASTIC TO 92 TO 72 1 2 TRANSISTORS SYMBOL C C BIPOLAR B B SIGNAL pap IE NPN IE BIPOLAR POWER SAME SAME S 0 JUNCTION G FIELO EFFECT FET P CHANNEL N CHANNEL 0 MOS G FIELD EFFECT IGFET MOSFET J SINGLE DuAL GATE GATE TO 5 T0 16 T0 39 14 02 133 14 1142 TO 3 T0 66 CATHODE ENDS CATHOOE ANODE 1 2 4 3 GLASS CERAMIC ENVELOPE BEAD 77 90 199 3 4 CLEAR OR TINTED CATHODE 2 METAL TAB CHAMFER 7 TRANSISTORS SYMBOL CASE E EMITTER B BASE C COLLECTOR SOURCE G GATE NM ee t 2 D ORAIN A ANODE K CATHODE MTI MT2 MAIN TERMINAL 1 2 A CONTROLLED hr RECTIFIER x a 31 14 SCR TRIAC 5 4 SYMBOL CASE SWITCHING 13 03 4 3 4 ZENER 5146 LIS
205. ilar method that gives tight cou pling and accurately locates the center tap The tight coupling is es sential to keeping the voltage spikes across the transistors to an absolute minimum In this type of circuit the spikes can easily exceed ten times the supply voltage if a poorly designed transformer is used causing transistor failure By using a bifilar winding for the primary the voltage spikes across Q1 and Q2 are well below the 60 volt rating of the transistors The stepped up voltage from the secondary of 71 is again stepped up by the voltage doubler circuit consisting of D1 and D2 It is then passed into flashtube FT1 Construction Perhaps the most demanding part of the construction process is the winding of 77 Even so the job is not difficult only time consuming The transformer should be wound in the following manner Start by winding the feedback loop its leads are labelled 1 through 3 in Fig 1 on the bobbin supplied with the ferrite core Use No 30 enameled wire This winding consists of 10 turns of wire interrupted at the 5th turn fora center tap connection Connect and solder 5 in 12 7 cm lengths of stranded hookup wire to the ends and center tap of the winding Label the leads 1 at the first turn 2 at the center tap and 3 at the final turn Then wrap the winding with a layer of thin Mylar or plastic tape Next comes the bifilar wound pri mary winding This consists of 27 double turns of No
206. in deterring intruders than are mechanical timers Shown in Fig C is a system built around a PROM for turning on and off house lights in a certain sequence Suppose that there are eight lights located throughout the house The lights can be con trolled by individual triacs with the triacs controlled by the outputs from the PROM Assume that 10 light patterns are to be used in the evening hours Word one can be a basement and a living room lights on com mand word two can be a living room and a kitchen lights on command and so on The various patterns of lights words can be selected by chang ing the address inputs which are connected to a 7490 decade counter A 555 timer can be used to change the outputs of which there are a possible 10 of the 7490 This in turn changes the lighting sequence for the house With this arrangement various lights in the house can be changed every so often to give the appearance thatsomeone is home and moving from roomto room by the type of ROM The two major types of ROMS are the custom programmed and the field pro grammable ROM With custom programmed ROM s the manufacturer places the binary in formation links or no links into the memory as specified by the user Cus tom programming of ROMs can be very expensive when only small quan tities are ordered To reduce the high cost of small quantities of ROM s manufacturers offer the field pro grammable ROM or PROM The PROM is an ordi
207. include details on programming as well as how to animate a video display 1 Part 1 August 1976 This first arti cle covered the construction of the Elf discussed the 1802 fundamentals of memory addressing use of registers and an introduction to programming 2 Part 2 September 1976 The sec ond article covered the use of a photo cell or switch as a flag input how to ex pand the I O lines a method of control ling up to 16 outputs and further pro gramming details 3 Part 3 March 1977 This section covered operating systems how to hook up a keyboard and how to expand memory A few reader supplied pro grams were illustrated 4 Part 4 July 1977 This article cov ered the installation of a single chip graphics interface showed some graph ics programming and how to animate T j H1 ES y IE OE TR we UNWRA OK MACHINE amp TOOL CORPORATION 3488 CONNER STREET BRONX NEW YORK N Y 10475 U B A o PHONE 1212 994 8800 TELEX 125091 TELEX 232395 CIRCLE NO 16 ON FREE iNFORMATION CARD ELECTRONIC EXPERIMENTER S HANDBOOK Digital Electronics Microcomputers 5 PRODUCT DIRECTORY Uses Altair bus See Module Bourds and Peripher als sections for directly interfacing equipment lses SWTP 6800 bus See Module Boards and Peripherals sections for directly interfacing equip menti APPLE COMPUTER APPLE II 6502 MPU computer with built in keyboard 6k BA SIC and 2k monitor in ROM 4k 48k RAM i
208. ine and speaker level signals Outputs microphone and line level signals Kit wired 120 165 ELECTRONIC CONTROL TECH ECT 100 20 slot card cage and motherboard for standard 19 in rack mounting Kit wired 200 300 Without connectors and guides sss 100 8KM 8k static memory Kit wired 295 350 16k RAM 16k memory eesse 555 635 Also available with 4k 8k or 12k on board for fu ture expansion 2k ROM 2k RAM ROM RAM board less ROMS eM m C E ER S 120 200 PB 1 Prototyping board sese 28 EXT 100 Extender card r 24 MB 20 20 slot motherboard sssss 60 EXTENSYS 64k RAM BOARD Has provisions for bank switching for expansion beyond 64k using multiple boards and software se lection of memory banks Wired 1495 oda ro MET 1195 SAR will iion Coin borde t eser M ET UE 895 FORETHOUGHT KIMSI MOTHERBOARD Altair bus motherboard for KIM 1 computer allows use of Altair bus peripheral boards with KIM 1 6502 system can also be connected to other 6502 and 6800 systems can run on same system as KIM 4 motherboard Power supply regulators on board power supply extra Witn one 100 pin connector KI WARGO Go oe coser sire RN 125 165 KIMSI PLUS Power supply 12 A Kit wired 60 75 Additlonal 100 pin connectors Kit installed 5 8 PRINTED CIRCUIT KI
209. ine screw fiber washer at the top of the transformer and a 6 32 nut Do not overtighten the hardware or you will crack the core render ing it useless Note Capacitor C4 mounts onthe board atop C3 as shown in Fig 3 When the circuit board assembly is completely wired temporarily con nectto the appropriate points on it red and black hookup wires for the posi tive and negative battery leads Con nect the leads properly polarized to a 12 volt battery or other dc source If the board and transformer are prop erly assembled you should hear a high pitched tone when power is ap plied This is the vibration of the trans former core as the circuit oscillates A VOM connected across R4 should provide a 250 volt reading if the input potential to the circuit is set to 14 5 volts If the circuit does not oscillate the phasing of the feedback winding of T1 may be incorrect in which case you can transpose leads 1 and 3 and try again Remove the temporary leads The type of flashlight body best suited for your timing light is shown in the lead photo You will have to drill two mounting holes for the circuit board assembly A third hole that per mits color coded battery and plug leads to exit the flashlight body should be lined with a rubber grommet Pass the leads through this hole and con nect and solder them to the appro priate points on the board Terminate the positive and negative battery leads with insufation booted all
210. ion For your 4 convenience we ll try to have a representa tive contact you to answer your ques tions Mail the card coupon or your letter to CIE 1776 East 17th St i Cleveland OH 44114 2 aYod e 37 ALTERNATELY FLASHING TAILLIGHTS BY TERRY A WILLIAMSON HEADLAMP up front to light your way and let people know you re coming toward them is great to have for night cycling But it isnt enough if you leave your rear unpro tected from oncoming motorists For rear protection you want something that will attract attention like the flashing light system described here Two lamps alternately flash on and off at a rate of about once a second to draw attention You can build the biker s rear safety flasher system for less than 10 ex clusive of generator About the Circuit As shown in the schematic diagram power for the flashing light system is obtained from a standard bicycle generator The generator should be rated at 6 volts and be capable of delivering 3 3 watts or more to the load The circuit used to pulse lamps 7 and 2 is a relay K1 driven by 555 timer C1 at a frequency of about 0 9 Hz with the component values Shown Other rates can be obtained by man ipulatingthe values of C1 and R2 inthe formula F 1 5R2 x C1 Lamps 7 and 2 flash alternately be cause of the arrangement of K1 s con tacts When one lamp is on the other is off Then when the next pulse from iC1 energizes K1 its con
211. ion for the NSL 446 is the house sitter shown in Fig 1 The pho tocell is exposed to outdoor light and it automatically turns on a lamp circuit when the sun goes down Potentiometer R2 and relay K1 provide current limiting for the photocell Half wave rectification is provided by D1 and C1 prevents relay chatter During daylight hours the pho tocell s resistance is low and the relay is kept energized The lamp circuit is thus turned off When the resistance of the photocell rises with waning light to wards the end of the day the relay cells is demonstrated in this construction project 4 l 1 4 W NEON te LAMP GE NE 57 Solid State PHOTOCELLS HOBBYISTS How light sensitive semiconductors are used in practical circuits BY L GEORGELAWRENCE drops out and the lamp circuit is ener gized The neon pilot light indicates that the unit is on and ready to operate Choppers When the circuit shown in Fig 2 called a photoelectric chopper is used with a conventional ac type oscillo Scope the latter can be used to display dc signals The photoceil PC1 is opti cally coupled to a watt neon lamp 1 Since the cell is gated on and off by the neon lamp s flicker frequency of 60 Hz a dc signal applied to the input of the cir cuit is chopped and appears as ac across R2 High dc input provides an analog increase in the amplitude of the ac output This arrangement works well in many non critical a
212. ional I O Includes data and status control ports hardware generated O strobes to simplify software Kit wired 70 80 MICROMATION JUMP START RAM board 4k with automatic jump to any preset memory byte on power up or reset has Switchable WAIT state for systems faster than 2 MHz protect both switches on top of board for easy access Pro vision for battery backup Kit wired 145 190 UNIVERSAL DISK CONTROLLER For hard or soft sectored standard or mini floppy single or double density On board memory pro vides RAM buffers PROM software storage In cludes RS 232 and 20 mA interface for terminal Controls up to three drives Kit wired 229 299 TYPEAWA Y Interfaces IBM I O Selectrics Model 731 735 to ELECTRONIC EXPERIMENTER S HANDBOOK Altair bus computers Includes solenoid drivers in put ports PROM software 70 W power supply all necessary cables and connectors Will interface 24 V or 48 V solenoids Kit wired 225 275 MICRONICS BETTER BUG TRAP Debugging board with four hardware breakpoint ad dress registers and a 16 bit clock Can detect ad dresses generate time intervals for real time clock interval timer single step etc With 8080A gener ates CALL instruction to any memory location when interrupting Occupies 16 bytes of memory Func tions include master reset wait on address inter rupt on address timed interrupt Compatible with vectored interrupt boards Wi
213. ircuit When pushbutton switch S2 is de pressed a negative going trigger pulse is applied to pin 2 of C1 sending the output at pin 3 to the high state This in turn energizes K1 and turns on the en larger lamp plugged into SO2 The initia tion of the expose trigger also opens up the IC s discharge circuit at pin 7 allow ing the C3 C4 or C5 whichever is switched into the circuit via S3 voltage to rise through LDH 1 as a function of the reflected light level seen by the LDR The voltage continues to rise at pin 6 where it is compared with an intrinsic control voltage that appearing at pin 5 of IC1 equal to 0 667 the supply volt 1978 Edition age When the rising voltage at pin 6 equals the fixed control voltage at pin 5 the flip flop in C1 changes state and discharges the paper speed capacitor through R3 and de energizes K1 As a result the enlarger lamp at SO2 extin guishes and the safe light plugged into SO1 if any comes on VARIABLE PAPER SPEED control H7 provides smaller changes in time as op posed to the rough changes provided by C3 C4 and C5 through S3 Control R7 multiplies the fixed values introduced by the fixed paper speed capacitors by a factor of 2 It should be a linear potenti ometer for easy calibration see lead photo after circuit is assembled Fig 2 Foil pattern for pe board is at right component layout shown at left A simple OR circuit D3 and D4 is provided for
214. irs or hobbies For that household item that needs repairing a radio TV model train jewelry appliances minor electrical repairs plumbing etc Save money repair it yourself Soldering with Kester is a simple inexpensive way to permanently join two metals When you Solder go First Class use Kester Solder For valuable soldering information send self addressed stamped envelope to Kester for a FREE Copy of Soldering Simplified LH KESTER SOLDER Litton 4201 WRIGHTWOOD AVENUE CHICAGO CIRCLE NO ILLINOIS 60639 13 ON FREE INFORMATION CARD 115 once by a single eight bit output byte Wired 235 PPCB Prototyping board AEE NORTE 45 WWB Wire wrapping prototyping board 20 EXC Extender board kit 5 46 MORROW S MICRO STUFF I O CASSETTE INTERFACE Single board O system with serial port RS 232 or 20 mA parallel port interface for three audio cas sette machines On board 512 byte PROM con tains all I O routines including cassette formatting deformatting and error checking and bootstrap loader Unused 1 O can be used for device control Requires 1k memory locations specify starting ad dress when ordering Kit wired oes 120 165 MOTOROLA The following boards are ail for Motorola Mi cromodule EXORciser MEK60002 or other com patible systems MICROMODULE SERIES M68MMO03 32 32 I O module Four parallel input and four output ports re
215. irst stage in the inverter is a low distortion sine wave oscillator C14A whose frequency can be adjusted by R1 The output of the oscillator is amplified and isolated from the load by a combination of an op amp and 67 amod o SON HOT ALLN puo ZH oot pun oc UAadatjog Aouanbad fiup jo oaa JUIS sjjoa LTT Duitootjop S40 81841 4 420t0d Bry TIS adiap 02 pasn sj 401njposo oipup duco do aqs v c1 big 85 89 FETE oe s r Liva Jo c NOI1 SOd 394 vVH2 NI NMOHS IS ind ats d QV ZII lOS m gt D N 1X31 33S E e Ak 4H 2i idl 11v8Q Yoi E LJ DiS 7 dii ag L2 29v MOG EE Pr Ola IOOP NI 60 1 8 3AiHa F 60 2 i0v09 8vIt NI d Cy Cao L 3 fo V JANO C i WO iQ OIG oy du OZY E Fi D3H MOG IH 8g ario fatio 4000 NOZI HEFTE 210 I 15 Sia on OID 19 39HvHO UO22 E HE ROLY 389 eed 2a UOZz2 Sid F eH wis NO 618 37200 C9 XB SIJES ppe sjuapisoi MdSauuO Zupuey pue sBeysod OO 7Z ppe siapio wed ayeredas oo pg je peog od oo ZI ie sowisuen GSOENZ paysew Xis GOC J sJoyxvaIq NDS LOC Ps i LIA 391211 LOLZE JB 1S 00 PG 1B LL Huno SUEN JOALIP c6L7 We CL 1SunuoJsugn ind mo iag Aporeiedos aqupear osiy Suipueig pue sdeisod Qo e snid 66 69 1 YUIS 1 amp 2 pue oseo Surpnjout yy aajdwo 9 90 LO PIORUN M N TOZ RD PA PISUSOI T cec pry noudojoAa pue uoigeosoy suog N WO4 ajqP ieAe BIE Zumo 2I 2J10N S10je nsuit Yopuels ee 3urs j22u 10 uinuiunie
216. is mounting ac receptacle T1 24 volt ac center tapped power trans former Misc 5 x4 x3 metal chassis box spade lugs printed circuit poard or perforated phe nolic board with clips three wire line cord with plug rubber grommet two conductor shielded cable for cell assembly hookup wire solder etc I 7TVAC OH S02 P ENLARGER Ta LAMP img D4 03 COMPOSE FOOTSWITCH LORI XI x2 BRACKET R7 PAPER HOUSING 500 1 SPEED R2 SEE Ji TEXT Qi MPFIO2 Fig 1 Light dependent sensor element changes circuit values to control enlarger 40 ELECTRONIC EXPERIMENTER S HANDBOOK 20S IOS 20S 10S system to color printing and multi con trast paper It is mounted on the edge of the easel where it looks down at the photographic paper and picks up the re flected light from a large area of the pro jected image the moment EXPOSE push button switch S2 is depressed A certain resistance value for a given light level is then established by LDR1 This re sistance coupled with C3 determines the on time of the enlarger lamp plugged into SO2 to extinguish Field effect transistor Q1 increases the input resistance at pin 6 of C 1 al lowing larger resistance swings for LDH1 with smaller capacitance values for C3 C4 and C5 This eliminates the need of inherently leaky electrolytics for these capacitors but requires that low leakage Mylar units be used in the fixed paper speed c
217. istor HEPS9100 2N 5308 Q2 Q5 Q7 Transistor HEPS0001 2N 5550 Q3 Transistor HEPS3021 MPSU03 Q4 Transistor HEP710 2N5400 z HEP 0001 es Q2 HEP SOOO 2D Xu uu A PLA JA a7on amp Transistor HEP241 2N5069 HEP Soo Resistors All 2 watt 10 tolerance un HS less otherwise noted R1 R2 3300 ohm l TR ON PC R3 R8 R 10 1000 ohm sore zi C2 je BOARD R4 R6 10 000 ohm indi pur R7 470 ohm l watt i k RI1 0 3 ohm L ij R12 Meter shunt see text R13 270 000 ohm R14 470 ohm R 15 10 000 ohm 10 turn potentiometer R16 10 000 ohm carbon potentiometer R17 10 ohm wirewound potentiometer S1 Spst switch SINK Ion JO mer i ECUR LIMIT Q l Sii a HEP 241 ie RII E zaron 270K Fig 2 The 50 volt supply is all d IL transistor and also has current ofl RI and voltage limiting f N L JI tcz o 50v4 J2 4 NOTE DO NOT USE CHASSIS AS COMMON SE SEE TEXT COM ue for the form Of course shunts can be purchased for most high quality meters but it is possible to wind the shunts for less expensive models The ammeter shunts should be mounted directly from the ammeter terminals to the shunt switch termi nals The 0 3 ohm resistors R17 and R13 can be mounted on the bases of the transistor sockets RECTI MDA920A3 RECT 2 MDAS 20A3 II VAC CHASSIS 16 Fig 3 The thre
218. istration stations throughout the United States transmit weather infor mation valuable to travelers and others on the ground Continuously repeated transcribed broadcasts on the FAA channels give wind speed and direction ceiling visibility temperature dew point and barometric pressure for airports and air travel routes the latter often corre sponding to highway routes PARTS LIST B 9 volt transistor battery C1 360 pF ceramic capacitor C2 5 pF ceramic capacitor C3 C8 C9 100 pF ceramic capacitor C4 C5 C10 C21 0 01 pF 16 volt ceramic capacitor C6 C7 C11 CI2 C19 0 1I pF ramic capacitor C13 C17 1 pF 16 volt electrolytic capaci tor C14 C16 C20 100 pF capacitor C15 220 pF ceramic capacitor C18 0 001 uF ceramic capacitor IC 1 Ferranti ZN414 IC2 MC 1306P Motorola integrated circuit J1 Phono jack L1 Transistor radio antenna coil Philmore No FF 15 or similar approximately 480 uH QI MPF 121 Motorola or MEM 621 Gen eral Instrument Corp dual gate MOSFET Q2 Q3 2N5172 transistor RI RI3 1 megohm V watt resistor R2 R9 R10 100 000 ohm watt resistor R3 8200 ohm watt resistor R4 82 000 ohm watt resistor R5 560 ohm watt resistor R6 100 000 ohm miniature potentiometer R7 33 000 ohm watt resistor R8 56 000 ohm watt resistor R11 10 000 ohm watt resistor R12 680 ohm V watt resistor R14 R16 1000 ohm
219. it Wires Amen AONE Uno CRE ne AEN AR rea Neate 89 119 ALS 8 ROM Resident assembly language operating system Stores assembles restores and links assembly language programs with line numbers ROM set requires GPM 268 ee a 159 ALS 8 on CUTS cassette paper tape 35 45 SIM 1 AND TXT 2 ROM Interpretive simulator allows pre testing of 8080 programs without crashing system TXT 2 adds au tomatic line numbering to ALS 8 also allows inser tion deletion and rearrangement of single charac ters lines or portions of lines ALS 8 and GPM re dauired BOM d sree Pe ee 60 4KRA 4k static RAM Kit wired 159 195 8KRA Bk static RAM Kit wired 295 375 16KRA 16k dynamic RAM wired enee 529 2KRO 2k EPROM 1702A module Kit wired 65 89 3P S I O MODULE Two eight bit parallel I O ports plus one control port one seria I O port 35 9600 baud Kit wired ent dU E BRU LS PO ME cde ere 149 199 VDM 1 Video display module Displays 16 64 character lines upper and lowercase Multiple programma ble cursors reverse characters blinking With soft ware on paper tape for interfacing with machine lan guage or BASIC programs Kit wired 199 295 CUTS CASSETTE INTERFACE Operates 300 baud Kansas City standard and 1200 baud CUTS Kit wired 87 119 SUBSYSTEM 8 Combines all basics necessary for practical use of
220. k additional PROM Us able as stand alone computer with suitable power Supply Ki Wired c A ceananie 0450 9600 RADIO SHACK TRS 80 MICROCOMPUTER Z 80 MPU computer in compact keyboard hous ing basic system includes 4k ROM with monitor and Level BASIC with string variables video graphics and cassette save and load 4k RAM in ternally expandable to 12k ROM plus 16k RAM to tal memory capability 62k includes cassette O and video output interfaces TRS 80 expansion bus for future peripherals has cursor control automatic scrolling and ruboUL t eco c oe duds 400 With 12 1n CRT monitor 16 lines 64 char 300 baud cassette recorder and backgammon black jack software cassette s s 600 RCA COSMAC MICROTUTOR 1801 MPU compact system with power supply 256 bytes of RAM two digit LED hex display and binary input switches Expansion connector for I O or memory Wired 349 EVALUATION KIT 1802 MPU single board computer 256 byte mem Ory expandable on board to 4k 512 byte ROM monitor Space provided for additional ROM serial 20 mA or RS 232 interface binary LED display battery backup option made possible by CMOS cir cuitry One eight bit parallel I O port Continuous and single step operation Wired 249 Microterminal For COSMAC Evaluation Kit Hex in put ues and eight digit LED hex ae Wired deos 140 SOUTHWEST TECH PRODUCTS 6800 Based on Motoroia 6800 MPU and i
221. l plate The battery can be sand wiched between the spacer and the wall of the utility box to keep it firmly in place Tune Up Initial tune up of the receiver is accomplished as follows Clip a short antenna to point A in Fig 1 Set sensitiv ity control R6 to minimum and adjust the slugs in T3 and then T2 for max imum sound output from the speaker on the desired FAA weather channel You may hear some air navigation stations in addition to the weather broadcast Connect the antenna to J1 Then set R6 to maximum sensitivity or as high as needed to hear the station Adjust L1 and T1 for maximum signal while reduc ing the sensitivity Remove the external antenna and readjust L 1 and T1 through T3 for best results with only the built in ferrite antenna The antenna coil is di rectional so rotate the receiver for best results ELECTRONIC EXPERIMENTER S HANDBOOK EMOTE control systems have al ways been popular as step energy and time savers Invalids find them eminently practical for control ling electrical appliances lights and radio and TV receivers Depending on the specific applica tion and the degree of contro desired a remote contro system can be ex pensively elaborate or very simple in design Perhaps the most practical in economy and design is the simple light activated system of the type de scribed in this article This system should cost roughly 19 for all parts It is virtually foolproof to operat
222. lays 16 lines x 32 characters uppercase can be wired for 16 x 64 with 10 MHz video monitor Occupies 1k memory space Text scrolling and cur sor software generated Adjustable density and left hand margin Assembled seseee 249 GHOST 8K EPROM BOARD Uses 2708 EPROMs Can be addressed to any 8k memory boundary including E000 to replace MIK BC Wired d d et dta e uds 119 Ghost Extender Board esses 25 GODBOUT 4K ECONOROM Comes with editor assembler and monitor routines for BOBO KI 4 odo oh eet nan emt rem cere Ee eI E 265 8k EconoRAM II Addressable in separate 4k blocks Kir obeseder eur eoo Cru tede 164 10 slot motherboard ccc ee HH 85 18 slot motherboard with connectors 118 Terminator Board Adds active terminations to bus to minimize noise Overshoot and other interference Plugs into one Slot M UD SEN 30 HEURISTICS SpeechL ab l Voice input for computers with microphone and software Requires 64 bytes of storage per spoken word Kitiwired ederet a iens 249 299 HOMESTEAD TECHNOLOGIES HTC B8P BREADBOARD MODULE Altair bus module board with built in breadboard sockets for circuit development 138 New compact 24 piece kit of electronic tools for engineers scientists technicians students executives Includes 7 sizes screwdrivers adjustable wrench 2 pair pli ers wire stripper knife 2 alignment tools
223. leads and the LED will indicate the type If the transistor being tested is not good either open shorted or leaky neither indicator may come on or one or both may light at more than one switch setting The Identometer will not check FET s nor will it work in circuit When checking power transistors particularly germanium types there may be some unpredictable results due to the high leakage current associated with these transistors 1978 Edition Put more punch in your work With a Greenlee Chassis Punch you can punch clean true holes in seconds Round square key or D In 16 ga metal hard rubber plastic or epoxy Available at radio and electronics parts dealers Write for catalog E 730 Greenlee Tool Co Rockford Ill 61101 GREENLEE TOOL CO a subsidiary of Ex Cell O Corporation CIRCLE NO 10 ON FREE INFORMATION CARD 4977 ciTIZENS BAND K HANDBOO CITIZENS BAND HANDBOOK by the editors of POPULAR ELECTRONICS has it all all the authoritative infor mation you need on CB two way radios to make an in telligent buying decision for transceivers antennas and accessories Here s a partial look at what the experts have packed into one volume B You ll have over 500 CB models at your fingertips fully described with technical specifications features latest prices and photographs B The latest 40 channel CB transceivers antennas and accessories are covered in detail B A
224. lel Interface a an 150 H11 Computer with LSI 11 16 bit MPU accepting PDP 11 software 4k x 16 dynamic RAM expand able to 20k backplane power supply with switching regulators and full circuit protection I O interface DEC software package with editor PAL 11 assem Thousands of copies of our in novative book on microprocessors are in use by hobbyists engineers and designers worldwide Now MICROCOMPUTER DESIGN is avail able for only 14 95 at your nearby computer store or direct from the publisher Over 400 pages packed with hard to find details like these e 8080 circuits theory of operation e Vectored interrupts for all 8 bit central processing units e Efficient bus structure design e Interfacing to timers A D con verters keyboards digits and other O devices e Plus much more martin research 3336 Commercial Avenue Northbrook IL 60062 312 498 5060 I 0 Please send capies of MICROCOMPUTER DESIGN at 14 95 20 outside USA O Enclosed is Residents of l Hlinows add 5 sales tax O CHARGE 0 BankAmericard O Master Charge Account Exp Date i Master Charge Interbank 4 numbers over vour name Signature u Print Name r Address City State Zip cuu ceca 102 bler linker on line debugger I O executive BASIC and FOCAL kit with assembled MPU 1295 4k 16 static RAM ooo cee ceccccecenceenersnes
225. loopy until we couid giv3 you a 3epe 1de ble dual system at he right price The MF 68 is a complate top cuality mifloppy for your SWTPCZ Cornauter he kit has controller chassis cover pcwer 500 Terninal W onitor memory 100 4K or 250 8K supply cables assembly instructions wo The CT 61 terminal kt offers thee Other SWTPC peripherals include hichly reliable Shugart dives and a premium features 64 chavacter ires 250 PR 40 Alphanumeric Line Printer diskette with the Floppy Disk Opxratra Loper lower case leters switchable cn i Muha ei A E m matrix System FDOS and disk 3ASIC A flappy trol character pnr inc wo d highdighting 75 line minute speed compatible with is no better than its operating sys em end full curso cont ol 110 12CC Baud serial our 6800 computer e MITS IMSAI the MF 68 has one of the best a a lao e Riera and many others seperately 79 50 AC 30 Cassette Interface System An optional 850 MF 6X kit excer ds t2 the CT 64 is 325 the 12 Mdz C VM writes reads Kansas C y standard tapes system to four drives monitor 175 controls two recorders Usable with other Mud LL MEN c cc c rc aE computers and other peripherals now Enclosed is 250 for the PF 40 ine P inter and to come 1 990 for the ful system shown accva 79 50 for Z C 30 Cassette Inferece MF 68 Miniflop y CT 64 Termine with Addtional k memory boards al S 0 CT VM Monitor Add tional amp mem
226. ly 1 3 volts the level recommended by Ferran ti If you wish once the pot has been set to provide the proper voltage you can remove it from the circuit and replace it with an appropriate value resistor More ideas By letting your imagina tion run free you can visualize many other applications for the ZN414 For ex ample how about using the IC as a fix ed tuned i f amplifier on 1 75 MHz and a AUDIO OUTPUT 8 Fig 3 Receiver performance is improved with voltage regulation and agc isolation precede it with a simple 2 to 54 MHz converter for shortwave listening Or how about deliberately introducing some r f feedback that would allow the IC to oscillate for demodulating SSB trans missions You might even try replacing the LC resonant circuit ahead of the IC with a series resonant crystal to obtain selectivity suitable for CW reception You can see that the ZN414 IC is one of the most unique and versatile building blocks offered to the experimenter n re cent years We predict that readers will find dozens of interesting applications for this versatile device once they be come acquainted with it 2 PIN OUTPUT gt gt gt perro PIN S degree of automatic gain control agc And the best is yet to come the ZN414 can deliver a power gain of 110 dB While Ferranti specifies the ZN414 s fre quency range as being 150 kHz to 3 MHz the IC has been operated successfully at a frequency as high as 7 MH
227. ly compatible with EXORciser system Choice of three configurations card cage or rack mount chassis various support boards and peripherals M68MMCCOS Five card cage aiee 168 M68MMCC10 10 Card cage sinri 198 M68MMLC1 10 card chassis with power supply and lanes re s o p AA LR o 635 M68MM01 MM1 Monoboard Microcomputer 1 with 6800 MPU sockets for 4k ROM 1k RAM six paral 2 MAS T elei ctore ces ONE SRM ees 485 M68MMO1A Monoboard Microcomputer iA as above but with four parallel I O ports one RS 232 senahpo rio cord NE ee c DE 495 M68MMO02 MPU module MPU clock power on re Start timing and control and refresh signals 350 EXORCISER 6800 MPU system designed for emulation of any M6800 microcomputer configuration MPU Debug and Baud Rate modules supplied can accommo date up to 12 other modules With cabinet and pow BOSD IY dede ient E DARE cetus 2600 M amp R GEMINI 68 Single board computer with 6800 MPU bus expand able via double sided 22 pin connectors Includes MIKBUG monitor ROM RS 232 and 20 mA serial I O 128 or 384 bytes RAM Baud rates selectable 110 or 300 Computer requires 5 V 1 5 A addi tional 12 V 150 mA total for RS 232 Wired and tested CPU board with 128 bytes RAM secen 260 CPU board with 384 bytes RAM 280 8k RAM Board pin for pin compatible 270 8k EPROM Board yo ences eg oe n i cYv HER 90 NATIONAL SEMICONDUCTOR SC MP Uses SC
228. memory power supply interfaces for audio cas NOTICE TO READERS We consider it a valuable service to our readers to continue as wehave in previous editions of this guide to print the price set by the manufacturer or distributor for each item described as available at presstime However almost all manufacturers and dis tributors provide that prices are subject to change without notice We would like to call our readers attention to the fact that during recent years the Fed eral Trade Commission of the U S Gov ernment has conducted investigations of the practices of certain industries in fixing and advertising list prices It is the position of the Federal Trade Commission that it is deceptive to the public and against the law for list prices of any product to be specified or advertised in a trade area if the majority of sales of that product in that trade area are made at less than the list prices It is obvious that our publication cannot quote the saies price applicable to each trading area in the United States Accord ingly prices are listed as furnished tous by the manufacturer or distributor It may be possible to purchase some items in your trading area at a price that differs from the price that is reported in this edition The Publisher 100 sette TTY RS 232 and two parallel I O ports Memory or I O expansion capability within cabinet expansion chassis available Wired 525 4k RAM
229. memory chip being accessed KUE at Ore UE 100 CP Control panel with 48 LED binary indicators for ad dress data status I O and state control switches include single step and hardware breakpoint Kit M M Mom LM T 190 LIF Line printer interface for Okidata parallel printer with full ASCII character and control capability Kit PEE CERES 200 EXT Extender board eeemm 25 CANADA CL2400 REAL TIME CLOCK Keeps time in 24 hour format hr min sec direct output to processor time automatically updated without using processor time generates periodic in terrupts at programmable rates Can be used as clock event software timer computer use log real time control system Usable with assembly lan guage or BASIC Requires 300 mA 8 V 50 mA 16 V KIE WITBd eos is ey 98 135 POWER CONTROL SYSTEM Interface board for power control of external de vices double isolated for safety Low voltage on board switching controls external power Switching unit Controllable by BASIC or assembly state ments Consists of PC3216 Control logic interface board 16 indepen dently addressable control channels accessed through a single user selectable peripheral ad dress Requires 8 V 270 mA 16 V 170 250 mA Kil WirBd oe ee eee d 189 240 ELECTRONIC EXPERIMENTER S HANDBOOK PC3202 Power control unit Single outlet remote power control unit switches 120 V a c loads up to 400 W c
230. mmands possible with serial interface IMB 01 System Motherboard Holds five interface boards one connector board with buffers and status LEDs Additional motherboards may be daisy chained to connector board Kit wired 28 38 IFB 02 Power Relay Board Controls four a c or d c circuits up to 300 W each 250 V max Kit wired Dr S E MT NC MM t 58 68 IFB 03 Prototyping Board seessssnes 15 IFB 04 Reed Relay Board Controls low level Signals can also dial phones Uses four reed relays Kit WILOO ce octo A a E N EN 36 46 IFB 05 Remote Driver Board Controller for four remote interface boards connects to remote boards through 5 V circuit Kit wired 29 37 IRB 01 Remote interface Remote switching board Switches 115 V a c 300 W with 5 V control signal from IFB 05 Kit wired ees 17 25 ISB 01 Serial interface Allows control of XPRES sys tem through serial ASCII port 20 mA RS 232 or dr ity WOO T S oe stat etico 48 58 ICB 01 Cabinet for XPRES system 38 CROMEMCO CGI TV DAZZLER Graphics interface 128 x 128 64 x 64 or 32 x 32 element resolution software selectable output in color eight colors available or black and white 16 gray scale intensities Alphanumeric output also available Requires RF converter or direct video in 1978 Edition put Uses two bus slots draws 1 4 A 8 V 50 mA 18 V Kit wired
231. monitoring LED s can also be mounted in rubber grommets on the front panel An on off switch can be used in the primary of 77 or the com pander power supply can be plugged into a switched receptacle on the preamplifier System Hookup The compander will work with any amplifier that deliv ers two watts or more of output If you have a separate preamplifier power amplifier setup use the hookup shown in Fig 3A Use shielded audio cables to interconnect the three de vices Be sure the hot side of the amplifier output is fed back to the compander If you have an integrated unit use the hookup shown in Fig 3B Connect a shielded audio cable from the tape output jack of the amplifier to J5 of the compander and another shielded cable from J2 on the compander to PREAMP J3 INTEGRATED AMP TAPE TAPE MON OUT the tape monitor jack on the amplifier By switching the amplifier s tape monitor to in the compander will be put into the circuit Checkout With the system properly connected be sure not to confuse the channels and operating adjust each channel s calibrate control R70 and R11 until the front panel monitor is just illuminated Proper adjustment here provides the best linearity and channel balance Working with one channel at a time place S7 in the EXPAND position the sensitivity control R7 at minimum and the depth control R6 at max imum Turn up the volume on your sys tem to the most comfor
232. mple which a moderately lengthy program the assembler translates into the equivalent binary codes Machine code and assembly lan guage programming both require that you learn to do things the computer s way To add 2 and 2 for instance you might tel the computer to load 2 into one register to load the other 2 into another register to add the two figures together and store the result and then to output that result some place where you can see it It would be simpler if you could just say PRINT 2 2 and get results High level languages such as BASIC the most common language in hobby computing APL COBOL FORTRAN and so on let you do just that they feed the computer whole binary instruction chains in response to a single symbol or English word of instruction Also where machine code and assembly language programs will only work on the MPUs THE WORLD OF HOME AND Wed SMALL BUSINESS COMPUTING MONTH AFTER MONTH LOOK TO INTERFACE AGE MAGAZINE FOR THE LATEST fi INFORMATION ON THE DYNAMIC WORLD OF PERSONAL COMPUTING Use your personal computer for auto repair work bench controller teaching machine central informa tion bank and design test center Control your small business with your own real time accounting and inventory control system Set your computer to turn sprinklers on and off manage a household security system even feed your dog Establish a recipe bank to plan daily meals and generate i
233. mplete module boards MTX 816 Video RAM for eight lines 16 characters uppercase ASCII 128 bytes ssss 179 MTX 1632 512 byte VRAM 16 lines x 32 charac ters upper lowercase ASCII Drives up to 25 TV WiOMMonSe ue cu m cx een 225 MTX 1632SL Externally synchronized version al lows output to be mixed with or superimposed on Diner IMAGES Sic ons d tS e 225 MTX 2480 24 lines x 80 characters upper and lowercase half intensity blink inverse video low ercase requires long persistence CRT phosphor a E E Ee MS MM M I a 395 MTX 256 2 Graphics board 256 x 256 individually addressable dots Color or grey scale available Light pen cursor plot point plot alphanumerics and ROM screen patterns may be implemented On PC board with 44 pin edge connector 630 ALT 2480 Altair bus compatible board with MTX 2480 4k video RAM providing 24 lines x 80 upper lowercase ASCII strappable for two pages of 40 characters per line allowing use of low band wich onto code et ene eT es ees 295 ALT 256 2 Altair bus compatible board with MTX 256 2 graphics VRAM two may be combined for grey scale or color operation 395 Character fonts 1632 and 2480 may be supplied with upper lowercase ASCII uppercase ASCII Greek General European and French character fonts at no extra charge Japanese Kata Kana British German math symbols etc available for 150 per order Custom design
234. mponents as shown Mount the probe tip in the board s end slot as follows First place the tip in the slot and secure it with a couple of turns of bare solid hookup wire passing the wire through the four holes provided Heat sink the cathode end of D1 Then liberally apply solder along both sides of the tip where it joins the foil pattern Prepare the ends of two 5 in lengths of stranded hookup wire Sol der these wires to the holes shown Then prepare one end of the coaxial cable and solder the inner conductor to the hole on the board and the shield to the hole Carefully spot on the body of the penlight flashlight the three holes for the LED s using the board assembly to guide you The exit hole for the coa HOW IT WORKS The memory probe Fig 1 is powered by the circuit under test Diode D2 pro tects the probe should the wrong hookup be made to the power line The combination of D and A provides over voltage protection Diode Df buf fers C1 froin excessively high inputs and insures a high input impedance bet ter than 75 000 ohms with a high input Transistor Q1 provides a high input impedance and serves as a buffer for the input of A1 in C1 When the probe tip is not terminated pin 11 of C1 is low and pin 1 goes high Inverting through A3 and double inverting through A1 and A2 LED1 and LED extinguish With a low input 0 8 volt or less pin 1 of A1 goes low Then by double inversion through
235. n der 10 used f 2 8 normal motion CRT BREAK CATHODE LEAD AND INSERT Inve THIS NETWORK ION TO SCOPE CIRCUITRY opening smallest f number Use a 50 watt lamp to illuminate the test pat tern and position the lamp unti an image appears on the screen Adjust the distance between the image sen sor and thelens by varying the spacers until the test pattern is in the sharpost focus Then secure the pc board tn place To adjust tne bias lamps darken the room so that no ambient light reaches the image sensor Make sure that R1 is at maximum resistance lamps out Adjust the scope s brightness control until the dot pattern can just be seen and then increase the brightness of the bias lamps until the scope pattern just starts to get brighter This is the correct setting of R1 Place the cover on the chassis so that no ambient light reaches the image sensor Cyclops is now ready for use Al though the resolution may seem to be on the low side for observing fine de tails you will note that the appar ent resolution seems to increase when viewing a ive scene especially one with motion 91 BY MARTIN MEYER Build a FOR 100 HE COSMAC 1802 microprocessor can serve as the heart of a relatively inexpensive about 100 microcomput er trainer that also features powerful ap plication and expansion capabilities The microprocessor circultry here can also serve admirably as the basis for a var
236. n expert evaluates new 40 channel CB radio power and performance B Manufacturers specifications are decoded so any one can read a spec sheet B What to look for when buying a transceiver Mobile antenna types and performance judgments How to sound like a CB pro when you re transmitting Tips on eliminating ignition interference B How to prevent CB theft This packed with information Handbook is the CB publi cation you ve been waiting for Only 1 95 aS a a Siam SS Se CITIZEN S BAND HANDBOOK Consumer Service Division 595 Broadway N Y N Y 10012 EEH 78 Please send the 1977 CITIZENS BAND HANDBOOK I m enclosing 2 50 1 95 plus 55c for postage and han dling Outside U S A 3 postpaid Print Name Address City State Zip Residents of CA CO FL IL MI MO NY STATE DC and TX add applicable sales tax Postage and handling charges non taxable 79 Protects Food Investment BY FRANKLIN C WILLOUGHBY F YOU have a home freezer unit you probably have a sizable investment in stored food All that food can be lost if for some reason the temperature inside the freezer rises to the thaw point For about 15 you can build a thaw alarm to warn you of rising temperature long be fore the thaw point is reached The thaw alarm is adjustable over a temperature range of 0 F to room tem perature By adjusting it to trip at 10 F the freezer can be opened to put in or take out fo
237. n this and other publications you may have trouble understanding at first just what s going on But once it s all ex plained the terms at least become easy to understand What is a Computer Basically a computer is a collection of electronic hardware that accepts data from the out side world makes logical decisions based on this data and its stored instruc tions manipulates the resulting data and then outputs the results in a form that can be understood A computer system usually includes the computer itself and several periph erals used to communicate or store data and programs The computer itself usually consists of the five hardware ele ments shown in Fig 1 the micro processor memory O input output ports clock and power supply all in terconnected by an electro mechanical bus structure But keep in mind that although this article is hardware orient 82 a eae See in A EL BY LES SOLOMON ed the best computer in the world can not add 2 and 2 without suitable pro grams of software just as the best software in the world is nothing but a piece of paper without the hardware to run it Microprocessor Sometimes called an MPU microprocessing unit or a CPU centra processing unit this inte grated circuit is the brains of the com puter There are many types of processors with the 8080 6800 and 6502 which were early starters and thus have lots of sof
238. nal ones use the ROM as lookup table trigonometry logarithms etc memories in calculators as micro instruction sys tems in computers and character generators for displaying al phanumerics on a CRT screen The following are examples of what you can do with an 8223 PROM Character Generator A seven segmentdisplay device can be used to create the numerals 0 through 9 a number of upper and lower case letters of the alphabet and some mathematical punctuation all with a single 8223 PROM chip Because the dis play has only seven segments it cannot form all 52 upper and lower case or even all 26 upper or lower case letters In Fig A is shown the logic diagram for an alphanumeric punctuation generator Beside it is the truth table we used for generating the 32 possible characters Note that the entire memory storage capability is used up in this truth table This truth table COMMON CATHODE LED DISPLAY U SEGMENT Fig A Once PROM ts programianed according to truth table at right it can generate numbers letters ete on 7 segment display device assumes a buffering transistor between the outputs of the 8223 and segments of the display The display can be either an RCA 2100 incandescent or common anode LED display For common cathode LED displays all B through B logic levels must be re versed All eight output lines from the 8223 PROM are used with one Output assigned to each segment of the display an
239. nary ROM that has all of its on chip fuses intact A 256 bit PROM would have 256 of these fuses one for each bit of memory The user can program information into the PROM simply by blowing selected on chip fuses The fuses are blown 22 open by passing a specific amount of current through them for a specified period of time The Signetics 8223 is an example of a 256 bit PROM It is readily available from a number of surplus parts suppliers for about 3 00 This PROM is organized into 32 words of eight bits per word Erasable PROM s ROM s are usu ally thought of as having permanent binary information programmed into their memories Once information is programmed into an ordinary ROM it cannot be altered Recently however a new type of PROM the erasable PROM has become available This type of PROM permits information stored semi permanently to be erased and new information to be repro grammed in One type of erasable PROM the 2048 bit MM5203 is made by National Semiconductor Corp It can be erased by concentrated shortwave ultraviolet light It is available surplus for about 9 00 The MM5203 is housed in a 16 pin dual in line package DIP with a quartz top that s transparent to shortwave UV light The 2048 bits are organized as either 256 words of eight bits per word or 512 words of four bits per word The advantage of the erasable PROM asopposed to the nonerasable PROM is that it can be used over and o
240. natigmn ot both WIES s ooo e qa oes 90 CT P Power supply Kit sees 16 MP L Interface for SWTP 6800 computer 35 Joystick potentiometer digitizer 40 Slide potentiometer digitizer sssssesss 36 PR 40 ALPHANUMERIC PRINTER Alphanumeric printer with 64 uppercase characters 40 characters per line 75 lines per minute Uses standard 3 in adding machine paper Has internal 40 character line buffer memory printing takes place at carriage return or when line buffer memory is filled 5 x 7 dot matrix impact printing Accepts data up to one character per microsecond or slower seven parallel data lines are TTL compatible and 112 enabled by data ready signal Used with any com puter having eight bit parallel interface including 8080 and 6800 machines Internal power supply Size 8Y4 H x 1012 D x 956 W Kit 250 PR AL Extra ribbon 5 eee ee er rene eoe eoo 5 MP L Interface for SWTP 6800 computer 35 SYLVANHILLS LAB X Y PLOTTER Plotter and interface kit mechanics assembled for interface to any eight bit TTL parallel port Pen hold er accepts any writing instrument or stylus 7 11 mm diameter encoded for 0 01 in pulse but 0 005 in optional Pen travel speed 2 5 in sec max with 24 V supply 4 25 in sec with 36 V Includes control of pen lift X and Y motion start and stop Drawing surface and
241. nd 35e Stamp lor 1977A Catalog California Residents Add 8 Saies Tax Dealer Information Available Aag RES ISIE 1 ames ELECTRONICS 1021 A HOWARD AVE SAN CARLOS CA 94070 PHONE ORDERS WELCOME 415 592 8097 All Advertised Prices Good Thru October 11 CIRCLE NO ON FREE INFORMATION CARD WIRE WRAP CENTER HOBBY WRAP TOOL BW 630 a Battery Operated Size C e Weighs ONLY 11 Ounces e Wraps 30 AWG Wire onto Standard DIP Sockets 025 inch Complete with built in bit and sieeve WIRE WRAP KIT WK 2 W WRAP e STRIP UNWRAP i e Tooi for 30 AWG Wire e e Roll of 50 Ft White or Blue 30 AWG Wire e 50 pcs amp ach1 2 3 amp 4 m 34 95 itatenes nor nriuded pre stripped wire 11 95 a WIRE WRAP TDDL WSU 30 WRAP e STRIP UNWRAP 5 95 WIRE WRAP WIRE 30 AWG 25ft min 1 25 SOtt 1 95 100f 2 95 1000ft 15 00 SPECIFY COLOR White Yellow Red Green Blue Black WIRE DISPENSER WD 30 e 50 ft roll 30 AWG KYNAR wire wrap wire 3 45 ea e Cuts wire to desired length e Strips 1 of insulation Specify Blue Yellow White Red New 31 Digit Portable DMM e Overload Protected e 3 high LED Display e Battery or AC operation a Auto Zeroing e imv t a D 1 abm resolution e Overange reading e iG meg input impendence DC Accuracy 1 typical Ranges OC Vonage 0 T000V AC Voltag
242. nditions the only power reaching headlight 7 and tail light 2 would come from the battery Now let us assume that the generator is delivering an output When the lead of the generator con nected to the anode of D7 is positive the generators output is ac rather than dc current flows through D7 to 1 and 2 Simultaneously the current also flows through D2 and charges C1 When the potential across C7 comes within 0 6 volt of the battery potential Q3 is cut off cutting off Q2 as well and isolating B1 from the now generator powered lamp circuit Transistors Q2 and Q3 will now remain off for aslong as the generator is delivering power As the bike is slowing to stop and the output of the generator falls off the potential across C7 will decay When it falls to more than 0 6 volt below B s potential Q2 and Q1 will switch on and pass power to the lamps from the battery Construction Little need be said with reference to construction aside from the fact that the components should be housed in a metal or other suitable utility box 39 Selects the proper exposure time and cuts down on photo paper waste AUTOMATIC PHOTO ENLARGER CONTROLLER F youre presently making photo graphic enlargements using a light meter a gray scale test strips or some other such device you d probably wel come a simple pushbutton device that automatically selects the correct expo sure and exposes your print for precisely the
243. nter faces for cassette 1500 char sec color video text graphics or mixed and video game paddies or joysticks Video output 40 characters x 24 lines uppercase normal inverse or flashing full cursor control Graphics 40 x 48 resolution 40 x 40 with four lines text in 15 colors high resolution graphics requires 12k memory 280 x 192 280 x 160 with four lines text in black white and two colors Apple BASIC has special color graphics and game com mands Assembled in case Weight 10 Ib With 4k 8k 16k 48k 1298 1398 1698 2638 Apple li Board Same less case power supply and id cab With 4k 8k 16k 48k oer ccu uc ee 598 698 978 1938 BYTE BYT 8 Altair bus mainframe with 8080 MPU 10 slot moth erboard 10 amp power supply real time clock MPa E ios E E rte van front panel with power and reset controls Kit 349 Chassis only less MP oes coos crcceeeaansnnne 229 BYT 8 CP Control pane with 48 indicators of ad dress data status I O and state control switches including single step and hardware breakpoint pec tte cites E m M 190 CENTRAL DATA 2650 COMPUTER SYSTEM BOARD 2650 MPU computer including 80 character 16 line video output 300 baud Kansas City standard cassette interface 1024 byte PROM supervisor with breakpoint and cassette routines PROM ex pandable cn board to 4096 bytes Includes 64 cha racter uppercase character generator space for ad ditional 64
244. ntific is the ideal personal computer complete with BASIC in ROM and plenty of RAM 4K for programs in BASIC Complete with an audio cassette interface the Chal lenger IIP uses a full computer keyboard not a calcu lator keyboard In addition the Challenger IIP comes complete with a full 64 character wide video display not a 40 character display The user simply connects a video monitor or home TV set via an RF converter not supplied and optionally a cassette recorder for program storage The Challenger IIP comes complete with a 4 slot backplane and case for only 598 00 Fully Assembled The Model 500 is a fully populated 8 x 10 P C Board with 8K BASIC in ROM 4K RAM serial port and Ohio Scientific Bus compatibility for instant ex pansion All you need is a small power supply 45 at 2 amps and 9 at 500 MA and an ASCII terminal to be up and running in BASIC And all for only 298 00 Super Kit The Super Kit is a 3 board set with a 500 board like the Model 500 without the serial interface The ROMs are configured for use with the in cluded fully assembled 440 video board to provide a full BASIC computer and terminal The Super Kit also includes a fully assembled 8 slot backplane board which gives you 6 open slots for expansion To be up and running in BASIC simply plug the boards together supply power 45 at 3 amps and 9 at 600 MA add an ASCII parallel keyboard plus a video monitor or TV set via an RF conv
245. od without triggering a false alarm The alarm s circuit see schematic is simple Thermistor probe TH formed from two Fenwall Electronics GA41P2 10 kilohm thermistors in series avail able from Allied Electronics as stock No GA41P2 for 3 95 each goes into the freezer and serves as the temperature sensor The temperature at which the alarm trips is governed by the setting of H1 Resistor R2 is a gate current limiter for SCR1 the tripping device while ca pacitor C1 prevents transients from trip ping the SCR when reset switch S1 is operated A Mallory No SC628 Sona lert is the beeper Power for the circuit is provided by an 80 ordinary 9 volt battery B1 Since cur rent drain when the alarm is on standby is only 30 pA BT s service life should be essentially the same as its shelf life Even when the alarm trips current con sumption is still only 4 mA To provide Thermistor probe inside freezer changes resistance with temperature to trigger SCR how continuous reliable protection ever it is recommended that B1 be re placed every six months or so Temperature adjustment via H1 is made only after the probe TH1 has been in the freezer for a half hour or so Rotate R1 s knob slowly just to the point at which the Sonalert starts to beep SEE TEXT Sounds alarm when freezer temperature rises above safe preset value Then back off just a bit until the alarm no longer sounds when
246. oint C is grounded This negative step is integrat ed to a pulse by C1 and C2 triggering IC1 When C1 is on the tone is heard from C2 in the form of a 4 second beep Construction Batter Up has been configured as three separate enclo sures a pitcher s mound a batter s box and a playing field Each enclosure is a standard Bakelite box Printed curcuit construction makes assembly easy but 1978 Edition the components could also be mounted on a perforated board If you choose perf board you can use the components placement diagram as a guide The playing field box is 734 x 43 x 238 19 7 x 11 1 x 6 cm The top plate is drilled in accordance with the photo of the prototype All lettering can be trans fer type while linework and figures can be made with an indelible ink felt tip pen Once the marking is completed a light coat of spray varnish will protect it from marring All LED s can be mounted directly on the main pc board Suitable etching and drilling and component placement guides are shown in Fig 3 The pc board is mounted in the box on machine screw standoffs so that the LED s protrude about Vv amp 3 2 mm above the top plate The battery holder is mounted under the pc board and the power switch on the side of the case Two holes are drilled one on each of the short sides of the case for the wires going to the Batters Box and Pitcher s Mound PI Vt l 4 e R35 e e cice Z e C3 e e
247. oller and Altair bus interface power supply cabi net all cables and connectors and software includ ing DOS and BASIC Controller can handle up to three drives Assembled sssss 1095 Additional drives sssssessess eee 649 IMSAI BBC 5 INTELLIGENT BREADBOARD Circuit development breadboard interfacing to IM SAI 8080 or other Altair bus computers Requires PIO6 6 interface Kit wired 435 635 BBC 3 Smaller breadboard expandable to BBC 5 Requires PI06 3 I O Kit wired 325 532 Key 1 ASCII keyboard upper lowercase for paral leh Ore oe OT e cele Re M cio EM 199 INTERNATIONAL DATA SYSTEMS TSM TEMPERATURE SENSING MODULE Self contained in minibox Requires only three wire connection parallel I O to computer system Also interfaces with IDS 88 UFC Frequency Counter Module see Module Boards Battery powered may be turned on and off by computer uses ther mistor probe which may be mounted up to 20 feet from TSM Measures 0 120 F 18 to 49 C resolution better than 0 1 C All needed software in cluded Kil WIIBO ee esr J a ee 24 44 DAC 8 DIGITAL TO ANALOG CONVERTER Self contained in minibox requires one eight bit output port Designed for applications requiring gen eration of audio frequencies 0 20 kHz and ap plications requiring eight bits of resolution for ana log voltage control Powered by internal 9 V battery With software
248. ompatible with PC3216 control board Kit WOO ccd aint oM SM 40 52 CGRS MICROTECH 6502 MPU 6502 microprocessor board for Altair bus with pow er up restart Level I Includes 256 bytes RAM Kit wired TU a M EMO T NN INE 100 130 Level ti With 2k RAM 4k PROM 2708 Kit wired M n nM n m 130 180 Prototype board 55 65 FRONT PANEL Address data reset memory protect and single Step switches data and address displays With motherboard for Altair bus MPUS also available without motherboard for use with Motorola EXORci sor boards Level I Binary displays Kit wired 90 100 Level Il Hex displays Kit wired 120 180 COMPUTALKER CT 1SPEECH SYNTHESIZER Voice generator board producing English speech from acoustic phonetic parameters transmitted on the computer data bus requires 900 bytes per sec ond of speech With 8080 driver software Direct Control Synthesis software address select switch Requires 8 V 170 mA 16 V 85 mA Wired 395 CSR1 Synthesis by rule software for 8080 35 CRC ENGINEERING XPRES DEVICE CONTROL SYSTEM Complete system interface package allowing con trol of up to 128 separate devices through one eight bit port and one strobed enable line System is mod ular and expandable in size System consists of motherboard and interface boards detailed below Serial interface to computer optional high level lan guage co
249. on the value being 1978 Edition measured since any practical value of voltage applied to the input causes some current to flow through the meter circuit If a positive voltage is applied to pin 2 of C2 current flows through D2 controlled by S3 PROBE the meter and part of R75 If a negative voltage is applied to pin 2 of C2 the current flow is from the positive out put and through D7 back to the input The current is actually from the input source since no current can be taken from the input terminal of the op amp This current is between two and three times the meter rating for full scale deflection In the prototype the cur rent was 2 8 times the 50 LA meter current or 140 pA The sensitivity of the meter has been reduced from 30 000 ohms volt to 6800 ohms volt but we have gotten around the diode barrier drop For a full scale indica tion of 500 microvolts the input re sistance of C2 now looks like 3 6 ohms 500 140 which is not very good for a voltmeter Thus it is neces sary to use C7 as a voltage follower The voltage follower has a high input impedance and low output im pedance due to the high open loop gain of the 741 op amp This makes it easy to match the high input impe dance required of a voltmeter to the low impedance required by the linear rectifier Some compromises have been made in the design of the range selec tion circuit due to the high offset cur rent of the 741 op amp A voltage
250. onics of this oscillator can be used in receiver alignment For example the second harmonic which falls at 456 kHz can be used for i f alignment A short wire antenna will serve to inject this signal into the radio being checked For dial calibration the upper harmonics 1978 Edition 71 Bl Fig 1 Simple audio generator can also 3 be used as a code Q practice oscillator RR or audio transistor R tester by substitution 3 11 Misc perf board and clips mounting hardware Fig 3 Three transistor audio amplifier can have either audio J2 or r f J1 inputs C1 47 wF capacitor Spst sy itch Miniature audio output transformer PARTS LIST 5 volt C or D cell hono connector optional 2N 170 transistor 2N 107 transistor 1S00 ohm watt resistor IO0 ohm w att resistor Battery holder transistor socket 2 dracone CT PARTS LIST B 1 9 volt battery C1 1500 pF mica capacitor C2 500 pF mica capacitor I1 Binding post Qi 2N2712 transistor RI 390 0 ohm resistor R2 3300 ohm resistor S1 Spst switch XTAL 228 kHz crystal Mise mounting hardware PROBE TIP PARTS LIST Q AUDIO OUTPUT Fig 2 This crystal oscillator can be used as a BCB i f aligner with harmonics usable across the whole broadcast band Battery holder and connector transis tor socket crystal socket PC or perf board R6 10 000 ohm miniature potentiometer B 3 volt
251. onnections made to this bus must be buffered if a CMOS device is not used The use of this bus not present in the original Elf design will allow easy sys tem expansion for added memory I O ports cassette or printer interface ROM operating system or an alphanumeric keyboard ELECTRONIC EXPERIMENTER S HANDBOOK N2 LOAD MRE AD MP TPA Sci sc RUN LOAD N2 DMA IN DMA OUT INTERRUPT R19 25 47K T 5VwV T5V R2 470N GNO TO CLOCK AND BUS il TPB A1 IC2 27 N Fig 1 The basic Elf circuit 1s modified as shown here Note that the IC s are now A prefixed and the passive components are renumbered PARTS LIST Al A2 2101 256x4 static RAM A3 A4 4026 quad bilateral switch AS 4023 triple 3 input NAND gate A6 1802 COSMAC microprocessor RCA A7 A11 4050 non inverting hex buffer A8 A12 9368 7 segment decoder driver latch Fairchild A9 743C173 latch AI0 74C922 keyboard decoder with 2 key rollover A13 4049 inverting hex buffer Al4 1861 video TV chip RCA A15 74L00 quad 2 input NAND gate Al6 7474 dual D flip flop A17 4013 dual D flip flop A18 7805 5 volt regulator CI 10O p F 16 volt electrolytic capacitor C2 1000 4 F 16 volt electrolytic capacitor C3 2 2 pF 16 volt electrolytic capacitor C4 C9 15 AF Mylar capacitor C5 C7 C8 25 pF i6 volt electrolytic capa cHor C6 not used C10 330 pF disc cap
252. or in the direction that yields the proper indica tion Tighten the bolt and recheck the timing to make sure it has not changed Stop the engine Remove the timing light and replace the hose to the distributor s vacuum advance dia phragm The timing of the engine is now correctly set It need not be checked again until the points are re placed e 49 HASE LOCKED loop circuitry has been popularized by its cur rent use in high quality FM stereo tun ers and by publicity accompanying the Dorren Quadraplex system of discrete 4 channel FM a quadraphonic FM broadcasting contender Though the advantages of PLL in FM reception have been used for many years in sophisticated military and space applications integrated cir cuit versions werent introduced un tit 1970 Lowered costs have spurred applications in many consumer elec tronics areas The phase locked loop is anaio gous to a servo system in the FM range Its behavior as a servo permits it to find and lock on signals tracking them 6 dB under the noise level As an electronic filter it can present a 1 passband to any frequency from 0 1 Hz to the r f region with excellent sta bility Using programmable dividers in its oscillator loop the PLL be comes a frequency synthesizer that can reproduce practically any fre quency from only one crystal This throws the door open to digital tuning of receivers and transmitters These are only a few of the areas where PLL is u
253. or the needs of service technicians a Stable instrument operated at a high degree of dependabil ity a trouble free performer Formerly RCA Inst Model 825 Easy to assemble wo modern printed circuit boards to reduce point to point winng Combined simple instructions and operat ing manual included Frequency response from 3 Hz to 5 MHz 1 5 dB The response at 3 58 MHz color TV carrier is 2 2 dB Special features include two preset adjustments to facilitate instantane ous oscillator lock in for TV vertical and horizontal Sweep circuits Test communication equipment including CB s Hi Fi s Radios and TV s Order your Scope Was 118 95 Now only 69 95 New Jersey Residents add 5 sales tax Inquire about other products ETI Products Dept 2640 107 Technical Home Study Schools Little Falls N J 07424 Enclosed is my check for 69 95 Send me Oscilloscope Kit postpaid Name TEE I ER Please print Address City slate r7p O Mastercharge 3 Carte Blanche O Visa BankAmericard 3 American Express Card Number inter bank Expiration CIRCLE NO 9 ON FREE INFORMATION CARD 111 pikes pM uq SK 3 Includes controller for 110 or 300 baud serial 1 0 RS 232 interface plus parallel O port for pa per tape reader punch Has option for uppercase only data Break ESC and LF sensing one ii BERTA o urere e erneuern pore onc ach EPR neces 389 FLOPPY DISK KI
254. ory boards at 25 I M Sou hwest Technical 995 for the Duel Minifloppy _ OrEAC Exp Date Products Corp ____ 325 for the CT 54 Terr inal Or UC _ Exp Date 219 W Rhapsody San Antonio Texas 78216 175 for the CT M Mor itor Name Address o London Southwest Technical roducts Co Ltd 395 for the 4K 6800 Computer Cty m Sate Zp 1 Tokyo Southwest Technical Products Corp Japan t 1 CIRCLE MO 23 CM RREE NFORMA ION CARD Chances are someone you know just bought a professional 312 digit DMM kit for less than 570 Fleet THOM RAGE Oooo eel ie l Chip Ter rr LIE Hun 10 AC WHT ABP GH i ril D Thousands of people have already bought the Sabtronics Model 2000 for two main reasons First its incredible accuracy range and professional features And second the incredibly low price of 69 95 People everywhere appreciate this bench portable multi meter They depend on its basic DCV accuracy of 0 1 1 digit its readings to 1999 and its five functions giving 28 ranges overload protection and 10096 overrange The 2000 is automatically appealing to hobbyist and professional alike With automatic overrange indication automatic polarity even automatic zeroing Best of all it s easy to assemble All the parts you ll need including the high impact case come right along with the clear step by step instructions The result is a professional quality 3v digit DMM
255. particu lar attention to the polarities of the diodes rectifier assembly and elec trolytic capacitor C7 and the lead orientations of the transistors and SCR Resistor R9 and diode D7 mount to the board by only one lead each The lead that goes to the board con nection for D7 is the cathode The anode of D7 and the free lead from R9 get soldered together to complete the circuit Trim off excesslead lengths on the foil side of the board Trim the leads of the photocells to 3 in 9 53 mm Solder the leads of LDR1 and LDR2 to the board s con ductors in the appropriate locations Let the photocells extend as far from the surface of the board as their trimmed leads will allow Fashion a pair of flat black tubes each about an inch long and just large enough in diameter to fit over the cases of the photocells These tubes they can be made from heavy con struction paper but not metal serve as light shields to prevent erratic opera tion of the system where ambient light ing is variable Select an enclosure that will com fortably accommodate the circuit board assembly The pc board layout shown in Fig 2 is designed for a two wire power System Hence the case should be all plastic or all Bakelite If you elect to go to a safer three wire system you can use a metal case but make absolutely certain that all three wires from the power cord socket and 77 the latter mounted on the case instead of the board assembly are
256. per line For transformer isolated sets only HCVM 1 Same for sets without power transformers 0 924 VECTOR 8800V MICROPROCESSOR PLUGBOARD Epoxy glass prototyping board with ground ard power busses provision for two heat sinks one supplied will hold two 40 pin eight 24 pin and 36 14 or 16 pin DIPs or other combinations 20 VECTOR GRAPHIC PROM RAM BOARD 1k RAM fcr stack storage no need to relocate when adding memory Room for 2k PROMs 17024 for monitor leader and utility routines Jump on reset to any desired memory address Without PROMs Kit wired aano a M 89 129 XYBEK PFAMMER PROM programmer for 1702A EPROMSs with 2k on board memory 256 bytes RAM 1792 bytes mro JM sce m 189 Extension cord with zero insertion force socket for programming PROMs outside the computer 15 HOBBY WRAP Model BW 630 Battery wire wrapping tool ONLY 24 5 pene COMPLETE WITH BIT AND SLEEVE OK MACHINE amp TOOL CORPORATION 3455 Conner St Bronx N Y 10475 1978 Edition 212 994 6600 Telex 125091 CIRCLE NO 18 ON FREE INFORMATION CARD 117 Get updated keep updated with BUTE personal computer field paan m vee ES BUTE Pasay I HN PE CH aav je TETIT The personal computer age is here Join Byte s 100 000 sub scribers and catch up on slashed prices of central the latest developments processors and other com in the Eo ETE field o
257. power supply keyboard and cabinet Kit wired 595 795 VT 4800 MAX As above but includes CRT med M NM D M 795 995 WINTEK B R B VIDEO TERMINAL Keyboard terminal available with or without TV monitor 53 key keyboard outputs all Teletype characters 64 character ASCII lowercase set Low ercase characters received are automatically dis played as uppercase 16 rows x 80 characters non blinking solid cursor 110 9600 baud serial in terface RS 232 standard 20 mA optional Less montre re ID MI CM T eee 695 With 9 in TV monitor eeeseeeceeeeeen 875 With 12 in monitor eeessseseeseeeeeeeeee 995 OEM board less keyboard and case 429 Same less power supply ssseeem 395 20 mA Current Loop Option sseeeseeeeee 39 COMPUTER MODULE BOARDS Boards listed below are adaptable for use with more than one company s microcomputer products Boards intended for use with only one company s computers are listed with that company s products in the Computer section Items marked with a single asterisk are for use with the Altair bus items marked with double asterisks for use with the SWTP 6800 bus ADVANCED MICROCOMPUTER LOGOS I Bk static memory 500 nsec Kit wired 248 298 LOGOS I Z 8k 250 nsec Kit 295 LOGOS iHX Same less RAMS Kit 130 LOGOS 16 16k static memor
258. pplications The excitation current can be derived from the scope s power supply LIGHT TIGHT _ _B X DC INPUT Po scm II IR CS120 Iw O v ee 117 VAC Fig 2 Photoelectric chopper for converting dc to amplitude variable ac for oscilloscope 1978 Edition 73 House Sitter stops conducting at night making relay drop out and turn on lamp The ac processing of a photocell s dc signal is desirable in many applications where the inherent drift of straight dc amplifiers including low cost IC s can not be condoned In the setup shown in Fig 3 for instance a motor driven wheel chops the light to the photocell The frequency of the electromechanical chopper is determined by the number of apertures in the wheel and the speed of rotation If for example the wheel is driven by a synchronous motor at 1800 MOTOR DRIVEN 4 CHOPPER WHEEL MACHINED APERTURES OPTICS S GAIN CONTROL JUI METER RECTIFIERS EXCITATION BATTERY le SINGLE SERIES STRING OF PHOTOVOLTAIC CELLS SECONDARY BATTERY FOR HIGH POWER DEMANDS 7 ANTENNA FERRITE I ROD ANT H MILLER 2001 1 5 BATTERY Tm EARTH GROUND Fig 6 Sun powered emergency radio receiver 74 PHOTOCONDUCTIVE CELL Z2N409 OR EQUIV SOLAR CELL B2M IR rpm and has 4 holes the effective chop ping frequency is 1800 60 x 4 120 Hz The chopped dc actually a square w
259. pply fan keyboard 9 in TV monitor and casselte recorder with 11k BASIC and assembler software on cassette 2250 System 6 Same in kit form less TM monitor and CasSSelle recorder ooo tetro Dd 4575 System 12 Same as System 16 less TV monitor cassette recorder and memory Wired 1175 System 2 System 12 in kit form less keyboard and fan wm E 735 Cabinet With five slot backplane and power supply power and reset switches Kit wired 235 355 Printer Interface Card Fits Poly 88 only RS 232 or 20 mA Kit wired X 65 80 Cassette Interface Fits Poly 88 oniy Kansas City standard 300 or 600 baud or Poly Phase 1200 or 2400 baud Kit wired a aa sss 65 85 PROCESSOR TECHNOLOGY SOL 20 TERMINAL COMPUTER 8080 MPU computer system in housing with built in keyboard Includes 16 line 64 character video in terface 1k RAM 1k ROM monitor 85 key keyboard with upper and lowercase cursor keys and arith metic keypad 1200 bit second CUTS cassette in terface two parallel and one serial I O ports 8 8 A power supply fan room for five expansion module boards With BASIC 5k and two video game pro grams on cassette SOLOS or SOLED personality module see below in ROM Kit wired aaa 1095 1495 Sol 10 Same but with 70 key keyboard 15 key arithmetic pad optional smaller power Supply 1k RAM one module board Slot Kit wired 895 1295 Sol PC As abov
260. pply rectifiers were mounted on their own small board under the bottom plate In the prototype a two sided PC board was used for the elec tronics of all three supplies The board was mounted in an 18 pin double readout card connector It might be preferable to assemble each regulator on a separate board for ease of con 1978 Edition RI R4 IK Ds C2 ON PC Ol OR PERF HEPS9IOO pF BOARD RIO l OO TEDE Gee eee E vm EI R15 LIMET ION CUR LIMIT mr 1 HEAT RI3 SINK 30 i Q4 l i HEP7O03 l AJ l Ee emu ee ee zi 9 SI MI RI4 A CO A C5 Msee TEXT 20pF J2QOCcOm 4 OJI struction installation and future maintenance The rear panel heat sink should be made of aluminum at least Ve thick and perferably The output transis tor for the high voltage supply was mounted on a separate heat sink at PARTS LIST C 1 I0 LuF 20 volt electrolytic capacitor C 4 0 01 HF ceramic capacitor C3 100 pF ceramic capacitor C4 4 uF 20 volt electrolytic capacitor C 5 20 pF 20 volt electrolytic capacitor 11 28 volt 40 mA lamp Dialco 507 3917 1471 600 or similar ICI IC voltage regulator 723 J1 J2 5 way connector red black MI 100 mA meter Monarch PMC7 or similar M2 0 18 volt meter Monarch PMC IIS or similar QI Transistor HEP715 2N5367 Q2 Transistor HEP709 2N 5249 Q3 Transistor HEPS9100 2N 5308 Q4 Transistor HEP70
261. properly connected to avoid shock hazard Before mounting the circuit board assembly in place drill holes through the case directly in line with the photocells Slide the light shields over the photocells and mount the board in place Operation The only device needed to trigger the remote control system is an ordinary flashlight Use a table lamp to check out the system While it is still plugged into the wall outlet turn on the lamp Then without switching it off unplug the lamp s cord from the outlet and plug it into SO7 Plug the line cord from the remote control sys tem into the wall outlet Shine the beam of the flashlightinto first one then the other photocell hole The lamp should come on and extinguish in step with the movement of the beam from one hole to the other The range of the remote control sys tem is directly related to the distance between the photocells The flashlight beam must be able to illuminate only one photocell at a time If you desire greater range than the pc assembly setup allows you can separate the photocells even more In this case use shielded cable between them and the circuit board e ELECTRONIC EXPERIMENTER S HANDBOOK 44 AMPING OUT whether it be in one of the new modern campers a trailer a tent or even a boat is one of today s most popular ways of getting away from it all There always comes a time however when we miss some of the creature comforts that w
262. puter that has vision For example the Cyclops Altair combination with 256 independentinputs outputs could be the basis for a robot that could be programmed to do a number of things while also being able to see its envi ronment and make any necessary cor rections in its actions Circuit Operation The Cyclops logic diagram is shown in Fig 1 Apart of C2 is used as a 1 MHz timing oscil lator One output of the oscillator drives the vertical scan counter which drives the horizontal scan counter The binary outputs of the scan coun ters are used to address the rows and columns of the MOS array As each of the 1024 elements is ad dressed two events occur within a period of less than two microseconds First the outputs of the vertical and horizontal scan counters are proc essed by a ladder type digital to analog D A converter then amplified by Q4 and Q5 respectively to produce the scope vertical and horizontal sweep This creates the raster on the CRT The second event occurs when the video information on the image sensor is read out amplified and used to vary the brightness of each of the 1024 dots that make up the raster and produce the intensity modulated image on the CRT Since both sweeps H and V and the video brightness information are in step at all times each of the 1024 elements on the sen sor has a corresponding point on the raster and the charge on each ele ment determines the brightnes
263. quivalent to an exclusive OR logic device which has an output only when the two inputs are at different levels The high or low signal requirements are provided by the transistor being tested and the instantaneous polarity of the ac line at the moment The combination is one polarity for npn transistors and the opposite polarity for pnp types 71 T Di IN4OO01 GREEN RED D2 IN4001 CU EE ONE PE ENEMIES S NES X This distinction provides the type identification With the correct phasing of the 3 4 secondary of T1 the exclusive OR signals are accepted by the LED driver that can react to a compatible signal during its half cycle of the ac Diodes D3 and D4 prevent slight differences in the voltage levels from turning on the drivers Construction To duplicate the pro 78 totype and use the pc boards shown in Fig 2 certain mechanical modifi cations must be made to two of the components Transformer T1 must have its four terminals cut to a size that can fit into the pc board As shown in Fig 3 two more tabs must be added to terminate a new winding The molded plastic form of this transformer allows adding the two new terminals 3 and 4 on the schematic The six terminals will DI D3 LEDI LED2 Light emitting diode Calec PARTS LISTS D2 1N4001 diode gt D4 1N914 diode tro K4 559 or similar QI HEP736 transistor Q2 H EP715 transistor R1 R3 1000 ohm V2 watt resis
264. r uses a slow 110 baud rate where an electronic CRT terminal can go up to 19 200 baud There are two types of serial O one is called a current loop because data flow makes and breaks a current usual ly 20 mA flow between the port and the terminal usually a teletypewriter the other called RS 232 uses a voltage that swings between a positive 1 level and a negative 0 level A parallel port looks at the entire 8 bit data byte at one time and delivers or accepts data in full bytes at a speed determined by the computer A special handshake signal keeps this port in step with the computer Obviously this approach is far faster than even the high baud rates used for serial data Parallel ports are commonly used for keyboards and for paper tape readers or punches A newcomer is the A D analog to digital converter port This approach is used to interface analog linearly chang ing signals with the high speed digital computer The most popular use by the hobbyist is for joystick controls for moving patterns around a CRT monitor as in game playing Clock Because a computer uses lots of digital circuits some means must be found to keep all of them in step to avoid chaos This is the purpose of the clock usually a crystal controlled oscillator The clock signal is passed down the bus to all elements but the power supply Power Supply Usually this is a well regulated conventional d c power source that
265. r H7 is mounted on the foil side of the board So that the two lamps can be adjusted when the pc board is mounted in place The purpose of 7 and 2 is to bias the image sensor with a dim un iform background light Although this is not absolutely necessary the bias light improves the low light level sen sitivity and provides better picture contrast Note that many resistors are mounted on end to conserve space on the board The power supply circuit is Shown in Fig 4 This supply is wired point to point using a terminal strip and can be mounted anywhere within the selected chassis The pc board is mounted on 34 ad justable standoffs behind the front of the chassis Mount the board tem porarily and mark a spot on the front panel that is directly in line with the center of the image sensor C7 Remove the board and drill or cut a hole just large enough to accommo date the selected lens Before mount ing the board permanently make sure that the distance between it and the lens can be adjusted slightly to permit focussing Connect the ground 8 volt and 17 volt lines from the power supply to the board Connect the four leads from the board ground vertical hori zontal and intensity to their respec tive color coded jacks on the rear panel The power switch S7 is also mounted on the rear panel and the line cord goes through a grommeted hole in the same panel Either one of two image sensors ELECTRONIC EX
266. r circuit was never used in AM re ceivers itattracted the attention of FM receiver designers who were looking for a method of stabilizing the mixer oscillator at 100 MHz The FM re ceiver already had a form of phase dis criminator to demodulate the i f signal By connecting the de component of Ihe discriminator output to a Miller tfect tube across the local oscillator the lat ter could be forced to lock in 10 7 MHz above the incoming signal to produce an exact 10 7 MHz i f The system was called automatic frequency control The budding TV recoiver industry looking for a way of locking the horizon tal oscillator developed several phase locked circuits notably the Syncro Guide and Synera Lock By the mid 1940 s phase lock was being used in military microwave and radar receivers When NASA fired the first space capsule its 10 milliwatt 108 MHz transmitter signals were ra ceived by a phase locked receiver whose ability to follow a signal below the noise level was considered pheno menal 3i FREF Thedifferential output pins 6 and 7 is useful in frequency shift keying This is a method of reproducing digital pulses by shifting the frequency of the input signal generally 1 kHz for a zero state and 2 kHz for a one state By connecting a voltage comparator across pins 6 and 7 the output pulses are cleaned and shaped They can then be interfaced with the following digital circuitry The 565 has two outputs
267. r e JOHN J CORTON Aav Sales LINDA BLUM Aav Service Manager e EDGAR W HOPPER Publishing Director LECTRONIC 14 20 24 28 32 38 39 40 43 45 47 50 56 61 63 65 6 71 73 75 77 82 87 92 p d LI 60Hz CRYSTAL TIME BASE POPULAR ELECTRONICS 19783 ELECTRONIC EXPERIMENTER S HANDBOOK Radio Hut Money back guarantee NO COD S Texas residents add 5 6 sales tax Add 596 of order f etc for postage and handling Orders under 15 00 Ideal for car CAm PEE vang DOR f add 75 cents Foreign orders add 10 for 60Hz output with an accuracy Oo postage 0059e typ Low power consump tion 2 5 mA typ Small size will fit most any enclosure Single MOS IC oscillator divider chip 5 15 volts DC operation This kit enables a MOS clock circuit to operate from a DC power source For your convenience call your BankAmericard or Master Charge orders in on our Toll Free Watts Line 1 800 527 2304 Texas residents call col ZIFF DAVIS PUBLISHING COMPANY lect 1 214 271 8423 PO Hershel B Sarbin Box 38323E SUNF HERIPAPE ONLY 5 95 each President under hew Philip B Korsant 2 for 10 00 Executive Vice President Furman Hebb SOCKETS Executive Vice President 14 pin low profile 16 pin iow profile 18 pin iow profile 74LS00 74L 145 28 pin low profile 74L802 74L 151 40 pin tow profile 74LS032 74LS153 74LS04 74LS155 74 805 74LS 156 Ls RESISTORS OVER
268. r games graphics and similar applications For use with Cro memco D 7A or similar analog interfaces Joys tick console Kit wired 65 95 CYBERNETIC MICRO SYSTEMS MODEL 34 SUPER PRINTER Dot matrix impact printer 34 column makes multi ple copies Full 96 character upper lowercase AS Cll font expanded print available two color red blue printing selectable Highspeed 120 LPM Re quires parallel interface Wired 995 THE DIGITAL GROUP KEYBOARD Keyboard with 76 keys including 128 character AS Cll numeric pad lighted uppercase key cursor controls two key rollover Requires 5 V KEY 1 Keyboard with interface cable 150 KEY amp CB With cabinet Kit wired 180 205 PT96 COMP PRINTER Impact printer 96 column 120 character second 12 characters per inch six inches inc Character set and pitch variable under software control Uses 8 5 in roll fanfold or cut paper Requires parallel I O With cabinet power supply and cabinet Also available separately Kit wired 595 675 ECONOMY TERMINALS ETI Displays 24 lines of BO characters upper case AS CII transmits upper and lower on 12 in CRT RS 232 and 20 mA interfaces 63 key keyboard scroll and page modes 16 selectable baud rates to 19 200 blinking underline cursor addressable au tomatic repeat on all keys tab fixed every eight characters Wired esti
269. r system Kit less diodes 50 CRT 1 TERMINAL 24 line x 80 characters full ASCH upper lower case Parallel interface Scrolling and paging with MSI PROM monitor for 68C0 see Module Boards Can use PIA 1 see above Includes controller board keyboard cabinet CRT power supply Kit Aum MM DEUS M 825 MCRT E TVT ENCLOSURES Holds terminal keyboard and CRT as used in CRT 1 terminal Removable keyboard mounting routed to accept SWTP KBD 5 keyboard 90 TVTE TVT ENCLOSURE Designed for SWTP CT 1024 TV typewriter Key board plate routed for SWTP KBD 5 keyboard with space at right for additional control keys or number pad space on top for setting CRT monitor 55 KDE TVT ENCLOSURE Designed for CT 1024 or similar terminals lower keyboard enclosure plus upper section to house 12 i PA NOUMIONIILO mE Ee IEEE 95 Keyboard or CRT enclosure Each 50 780 HIGH SPEED PRINTER Dot matrix impact printer five copies max 80 char line six lines in 60 char sec Sprocket fed paper up to 9 4 in wide Buffered input Full al phanumeric uppercase normal and elongated characters Less interface s sss 1495 PROM PROGRAMMER VERIFIER Programs PROMs directly from computer memory via parallel port Reads and compares PROM after writing to verify contents displays discrepancies and error message on terminal PR 1 For 1702A PROMS Wir
270. rcuits with CSC Proto Boards Sockets are already mounted on sturdy metal ground baseplates with non marring feet They re great for a wide variety of audio and digital projects and you save money by using components over and over again PB 101 940 solderless tie points ten 14 pin DIP PB 100 Kit 760 solderless tie points ten 14 pin DIP capacity 140 capacity 140 five point terminals plus 8 bus lines TE five point terminals plus 2 bus lines of 30 tie points each Comes cf 20 tle points each 4 5 W x 5 8 L x 1 4 H 114 x with pre assembled sockets two 5 way binding posts base plate 147 x 35mm 9 oz 26 Kg Price 29 95 all hardware 4 5 W x 6 L x 1 4 H 114 x 152 x 35mm 7 5 oz 21 Kg Price 19 95 EXTRA LARGE CAPACITY FOR MORE COMPLEX CIRCUITS PB 103 2250 solderless tie points twenty four 14 pin DIP capacity 354 five point terminals plus 14 bus lines of 50 tie points each plus 2 bus lines of 40 points 6 W x 9 L x 1 4 H 152 x 229 x 35mm 1 25 Ib 57 Kg Price 59 95 PB 102 1240 solderless tie points twelve 14 pin DIP capacity 188 five point terminals plus 6 bus lines of 40 tie points each and 2 bus lines of 30 points 4 5 W x 7 L x 1 4 H 114 x 178 x 35mm 10 oz 31 Kg Price 39 95 PB 6 Kit 630 solderless tie points six 14 pin DIP capacity Economical way to get Proto Board speed and convenience 94 five point terminals plus 4 bus lines of 40 tie points Comes with pre assembled socke
271. rd of sensitivity readings and in a period of a week you should see some sign of improvement e 31 IC DIGITAL LOGIC MEMORY PROBE Indicates logic state of circuit and detects pulses as short as 50 ns NE of the more vexing problems facing today s experimenter is finding a way to check the 5 volt logic devices that dominate the hobby con struction scene Lacking a high speed triggered sweep oscilloscope the ex perimenter is left defenseless in cop ing with the frequent 50 ns pulses that are more than long enough to trigger IC logic devices To cope with the problem without a scope however you can build the digital logic memory probe described here It is designed to indicate the logic state of a circuit providing detection capabilities for pulse durations as short as 50 ns The circuitry of the probe is housed in a penlight tube and derives its power from the 5 volt line and signal ground of the circuit under test The indicator system consists of three light emitting diodes LED s mounted in line at the end of the probe tube The top LED lights up for a logic 1 while the bottom LED illuminates for a logic 0 2 4 or more volts and less than 0 8 volts respectively The center LED comes on to indicate a positive or negative going transition as short in duration as 50 ns and remains on for 200 ms without regard to the time du ration of the pulse being observed This stretching feature provides ample time to observe
272. rding system in cluded Wide range clock 200 nsec 5 sec allows operation speed to be reduced for visual tracing of program action Includes power supply 1595 MARTIN RESEARCH MIKE 8 MODULAR MICRO Z 80 MPU modular computer Includes calculator type keypad and display PROM RAM board and monitor CPU other options 872 Includes 512 bytes RAM expandabie on board to 1k space for 1k PROM plus 1k PROM monitor mc MM MU E rey 495 880 Same but with 1k RAM expandable to 4k 2708 programmer with space for two PROMS 1k RISQUE STEM 675 881 Same with extra 1k PROM 4k RAM 795 ELECTRONIC EXPERIMENTER S HANDBOOK MIKE 3 MODULAR MICRO 8080 MPU version of MIKE 8 813 Equipped as 872 but with 256 byte monitor DI E MR MM ae 395 814 As above with added Debug PROM including 32 channel scope display output and display 495 822 As 882 but with 8080 power supply 5 V 3 A 12 V 0 8 A each plus debugging as 814 aboguBe c uL tC tear SCTE T 995 AT423 1 PROM RAM board Space for 2k PROM 1702 and 1k RAM aerer 78 AT424 4 Serial interface Two serial I O ports ES 232 20 MA oer eee a E E ER 179 AT423 PROM RAM board Space for 8k PROM 2708 and TK RAM era 119 AT424 4 Serial interface Two serial I O ports RS 232 and 20 MA eee eve rre 179 AT 405 4 4k RAM board seeeessss 179 KT9009 I O Kit Two pairs of I O ports one memory mapped one standard
273. re has a unique address code it and only it can be turned on by the selected address and control signals and told what to do with the incoming data For example if the selected device is a block of memo ry then it will either store or read the data If it is an 1 O input output port then it will prepare the data for use by the pertinent terminal or receive data and instructions from that terminal Memory When we speak of memory we usually mean the solid state memory devices that can be connected directly to the computer bus Mass storage memory devices such as floppy disks and cassettes will be discussed under Peripherals Since all digital data consists of com binations of binary 1 s and O s such data can be stored within groups of flip flops ELECTRONIC EXPERIMENTER S HANDBOOK al Matt which have two stable states called in terestingly enough 1 and O Each discrete 1 or O is called a bit and data within a hobby computer is usually in words 8 bits or 1 byte long although there are also hobby computers using 12 bit and 4 bit words A computer word though is much shorter than a human ane since it takes at least 7 bits to store a letter of the alphabet Even a 12 bit word can store only a single al phabetic letter Most hobby ccmputers can use a total of up to 65 536 bytes usually abbreviated tc 65k These 65k bytes can be made up of two types of memory RAM and ROM in any de
274. red only 180 MIDWEST SCIENTIFIC MEMORIES RAM 68 Bk RAM for SWTP 6800 Has battery back up provision Kit without with sockets PP MN OPEM OR e 249 299 EPR 8 8k EPROM Holds eight 2708s Comes with instructions on modifications for use of EPROM board restart vector MIKBUG start up routine Without with sockets cce 95 110 PRR 68 4k PROM RAM board holds 15 156 byte pages of 1702A PROM 3840 bytes total plus one page RAM Comes with modification instructions for use as restart vector in place of MIKBUG start up routine Without with sockets 95 120 Monitor In 1702A PROMs Replaces MIKBUG re tains full compatibility with all MIKBUG software plus additional and user features including CRT handler for CRT 1 see Peripherals Requires PERMET Ee nd d e eum E 275 Extender Card For SWTP 6800 50 pin bus Kit p v tac cM Een halo ps o 25 MINITERM ASSOCIATES MERLIN VIDEO INTERFACE O Combination alphanumeric graphics interface with I O and ROM facilities Alphanumerics 40 charac ters by 20 lines uppercase ASCII plus inverted video control characters cursors may be inverted blanked or normal under software control carriage returns may be displayed or may terminate display line ASCII and graphics may be mixed Graphics Normally software selectable for sparse 80 x 100 or dense 160 x 100 resolution super dense op tion 320 x 200 can replace
275. ro Hockey and Tennis games Easy hook up on any B W or Color TV Factory warranty 0811 Tic Tac Toe Shooting Gallery 0819 Orag strip 1 or 2 players Quadra doodle Doodle 0815 Spacewar 2 players 0820 Maze 2 players 0812 Desert Fox Shooting Gallery 0818 Magic Numbers computer logic 0822 Baseball 2 players T237 While w bracelat 22 96 T236 Yellow w braceiet 25 95 LED T325 White w strap 1324 Yellow w strap 0813 Blackjack 1 or 2 players 0814 Spittire 1 or 2 players 125 dia dam aqait 190 dia C209 Red 19 1 o Red yr xC 208 Green 451 xC111 Green 4 Orange 451 S S ACT Yellow 4 1 Yos vios 4 D C R ETE L E D C11 range 1 1 200 dia 185 dia 200 dia 085 dia xC22 Hed 10 51 xC526 Red 541 70556 Ren 2 MVbO0 Red 6 1 C22 bieen 451 40526 Green 4 1 05h Green C22 Yellow 451 xC526 Yenow 4 ST XC556 Yellow i INFRA RED LED xC22 Orange 4t X526 Orange ET 6556 Dange 451 SE EE ssl 22 AT 43 xC526 Clear 4 555 Cleat si Pat 1 00 MA DISPLAY LEDS P TYPE POLARITY HT TYPE PDLARITY HT MAN 1 Conn on Snore 20 235 MAGN dna Carmon phone orange in 0 75 MAN 2 5x Dor Matris 390 487 MAN 47 71 f nt nior nnde He1 ind 135 MAN 4 Common limp fe 125 3 1 00 DL Ot Common Anode red 300 99 MAN 4 amman Catra RF 19A NL 704 Common Cathode 300 85 MAN 7 Lanuron Anode XQ 1 25 non Lom nnn Apnd o
276. ro oe M Sr 269 369 8KSCZ Faster version for Z 80 Kit wired ome Tp 295 395 4KROM 4k read onlyp memory takes 1702A or 5203 EPROMs Address switch Kit wired 119 179 aauc Battery backup card for 8k memory Holds and au tomatically recharges Ni Cad batteries to protect memories when power is off Less batteries Kit WILGO nc Dele adopts vost Fu do caa eee 55 68 ELECTRONIC EXPERIMENTER S HANDBOOK SMOKE SIGNAL M 16 16K MEMORY BOARD 16k static RAM board for SWTP 6800 bus Allows Expansion to 32k without modifying computer ex pansion to 48k with simple modification to MPU board Requires 8 V 1 8 A from computer Wired ee ee 595 P 38 PROM BOARDS Holds up to 8k type 2708 EPROMS or pin compati ble ROM or PROM Switch selectable address can accommodate MIKBUG or MINIBUG II ROMs with interrupt vectors Switchable between MIKBUG and user PROM Requires modification to computer s 12 V power supply or PS 1 power supply below Wired 179 P 38 I Same with additional interface for Oliver Tape reader and Smoke Signal Broadcasting EPROM programmer includes tape loader soft NV CE seente Mediam omi mano uer EE 229 P 38 FF Same as P 38 I with addition of plug in in terface for ICOM Frugal Floppy see Peripherals includes one 2708 with ICOM bootstrap software ee manae E c utt SE EO 299 PS 1 Power supply 16 V 22 A will operate up to I d a RTL RR RR n RN 25
277. rogrammable interval timers Has vectored priority interrupts Baud rates software selectable 110 76 800 baud Requires 1A 2 8 V 80 mA 18 V 40 mA 18 V Kit wired oe cc it ect do iav 195 295 TRT CBL Cable for coupling TU ART ports to EIA D 25 inputs up to four required 14 4 MH2z Z 80 CPU CARD Extra high speed 2 80 microprocessor card using Z 80 specially selected for 4 MHz clock rate opera tion Clock switchable 2 or 4 MHz Automatically jumps to any desired 4k memory boundary when turned on no front panel required Monitor program supplied in paper tape available in ROM for 50 more Kit wired aseeseensa 295 395 DAJEN UCRI Universal cassette recorder interface Switch aono vn selectable baud rates from 520 to 41 000 baud maximum usable typically 5000 baud on cassette 12 000 baud on 7 2 ips tape switch selectable Tar bell Kansas City or other format Independent Switch selection of transmit and receive data inver sion for use with different recorders Level indicator light Relay option for independent control of two re corders independent latched input port for key board or other use Kit wired 135 175 Relay option a sae ours ono D tei edet E a 16 CR LB Cassette recorder interface Switch selectable baud rate 800 6000 baud and address independently switchable transmit and receive data inversion SYNC and level indicator lights inputs for l
278. s 175 Serlal interface 0 cccccccccccccses cece eceeeeteneneees 95 Parallel interface esee 95 IASIS ia7301 8080 MPU single board computer with built in hex keyboard and display 1k PROM monitor space for EE HO Gh c x 2k 1k RAM two I O ports plus audio cassette in terface LEDs signal end of tape read or write oper ations Requires 5 V 12 V only 5 V derived internally power supply optional Computer is built into a 500 page looseleaf programming manual computer board has plexiglass cover with cutout for Keys Wired uc edn re alee ae 495 IMSAI 8080 SYSTEM MPU board includes 8080A clock tri state bus driv ers and control signa timing Front panel control board plugs into one slot features large paddle handie address data switches and LED masks Has eight LEDs program controlled Power supply delivers up to 20A at 8V and 3A for 16V Heavy guage aluminum cabinet has room for up to 22 cards six slot motherboard standard four slot ex pansions and 22 slot motherboard optional Memo ry expandable up to 65k bytes or up to 1 M with In telligent Memory Manager option Rack mounted System is 20 00 more Many mechanical options fan connectors cables available Many hardware options including memory RAM PROM EPROM multiprocessors and shared memory I O inter faces disk drives video display and keyboard ter minais printers software including bootstrap
279. s of its raster dot A novel coding scheme is used for the video information Thirty com pletely new frames are displayed on the scope each second with each frame made up of 16 separate and complete scans of the image sensor The first of these 16 scans is used to reset the 1024 photoelements with 89 CI 5X AuF 15 valt electrolytic capacitor C2 C3i 2000 nF 15 volt electrolytic capacitar D1 D2 I NAM diode E d t amp l J ri IN 40 m BV E amp GND PARTS LIST F1 1 ampere fuse and holder SI Spst switch Ti 12 6 VCT filament Triad F 25X or similari transformer Fig 4 Power sippl y for canera can Be wired potnt ta potat qud mounted anywhere iH chasais the reset pulses generated by C7 C8 and C9 On subsequent scans the video information is read out When a particular photoelement is illuminated by a bright light from the image being sensed a video output pulse is developed each time that ele ment is addressed The video output pulses are amplified by Q7 and after gating by Q2 and Q3 to produce the scope intensity Z axis signal If there is no light on a particular element no video pulse is generated when that element is addressed For grey por tions of the picture the number of video pulses generated for each frame is determined by the intensity of the grey in the original image Several inputs and outputs are pro vided on th
280. s that the output voltage levels of the PROM are converted to the proper voltages and currents needed to move or position the track switches The PROM must be programmed with the appropriate binary codes The words w through w can then be the various track patterns that the train can have The one shot muitivibrator s out put is coupled to the CE input of the PROM so that the switches do TRACK ELECTRONIC 20 y 16 Sgt 6 l a e P ue v e ie me am e m ee e ka ELECTRONIC L pee SWITCH Fig B n model railroad system PROM would be programmed to control all possible combinations of switches on track 555 TRIAC FL LIGHT TIMER ws 8 LIGHT I PATTERN TIMER 8 er dd A 6 D Ao O i 2 goes 45v 5 io a PROM 4 6 8 sE 3 l ah 0 Co R AHE 555 TIMER DAY NIGHT TIMER Fig C Clocked by timer circuit 7490 counter delivers a 4 bit input to PROM which controls triacs to turn lights on and off not have voltage across their coils continuously With the PROM remembering the various track positions for the eight switches you need only select the pattern you wish and push a button to initiate the selection of that pattern Intruder Deterrent When you go away from home for a day or longer you probably use mechanical timers to turn on and off house lights to make it appear that Someone is home A PROM can be used for this purpose and is much more effective
281. se polarity and over voltage protection Price 44 95 HIGHLIGHTS e HI and LO LEDs blink on and off tracking 1 states at square wave frequencies up to 100Hz e PULSE LED blinks on for 4 second during pulse trains With square waves of up to 100KHz both HI and LOLEDS will be activated PULSE LED will blink continuously at 3Hz rate to indicate level transitions With duty cycles of less than 30 LO LED will light in addition to PULSE LED blinking at 3Hz With duty cycles of more than 70 HI LED will light in adaition to PULSE LED blinking at 3Hz Input Impedance is 100 000 ohms for minimum circuit loading Maximum input signal frequency is 10MHz 1978 Edition and O MEET MAX 100 CSC s 100 MHz 8 digit Audio CB RF Digital counter At 134 95 nothing else does so much for so little MAXimum frequency range 20Hz 100MHz MAXimum CB performance ideal for CB applications MAXimum visibility big bright 0 6 8 digit LED display MAXimum accuracy crystal controlled timebase MAXimum operating ease automatic no controls to set MAXimum range of applications use for audio through ultrasonic through RF AM FM and digital MAXimum portability completely self contained MAXimum versatility use with clip lead cable in line tap mini whip antenna etc MAXimum flexibility choice of four power sources MAX 100 is a portable high precision frequency counter that sets ne
282. seful There are in addi tion frequency shift keying for RTTY motor control FM generators touch tone telephone and stereo and four channel decoding Now that the price of PLL IC s has dropped below 5 00 the hobbyist and experimenter can add the PLL to their store of basic building blocks PLL Basics The PLL is a feedback system comprised of four basic ele ments Fig 1 a phase detector or comparator an external low pass fil ter an error correction ampiifier and a voltage controlled oscillator vco The vco is a free running form of multivibrator whose center frequency is determined by an external timing capacitor and resistor The vco output is presented to the phase comparator where it is compared to the incoming signal The result is an error correc tion voltage whose magnitude is a function of the phase and frequency differences of the two signals This signal is then filtered in an ex ternal low pass filter and amplified in the error correction amplifier The output of the latter is fed back to the voltage control input of the vco to complete the loop and cause the oscil lator frequency to approach more closely the frequency of the input Once the vco starts to change fre 90 HOW PHASE KCODKE DS WORK Theory and applications of an old circuit revitalized and refined by IC technology quency it is in the capture state and it continues to change frequency until its output is exactly t
283. segment LED readouts forming DIS1 Besides the data informa tion this circuit also accepts the strobe signal coming from A5 of Fig 1 the orig inal IC10 pin 9 The original EIf used eight discrete toggle switches to insert data In con trast Elf Il incorporates a calculator type hexadecimal keypad which is much simpler to work with As shown in Fig 4 the calculator type hex keypad contains normally open momentary close spst switches in the matrix The keypad is decoded by A10 which features a 2 key rollover The out put of A10 is used to drive data bus driv er A3 and at the same time also drive A9 The latter drives data bus driver A4 Keyboard decoder A10 contains its own internal oscillator used to sample the keys its frequency is determined by the external passive components The front panel circuit is shown in Fig 5 The RUN S4 LOAD S3 and MEMORY PROTECT S2 switches can be locked in either the on down or off up positions To use these switches simply depress to turn on and depress again to unlock and turn off Bus The Elf has been provided with an 86 line twin 43 bus structure to car ry the signals shown in Fig 6 Note that at this time only the even numbered connections are used excepting pins 1 and 3 which carry the 5 volt supply All of the 1802 signals are present on this bus which includes the system 5 volts ground and the 3 58 MHz signal from the video clock Any c
284. settings of the FIX ED and vARIABLE PAPER SPEED controls for the types of paper you are using Place the LDR bracket to look at an area of interest avoiding hot spots and sim ply make a small enlargement at differ ent settings of the controls Use low numbers for lighter and high numbers for darker areas Record the best setting on your package of paper This setting is now always used for that paper regard less of the magnification and film density or filter A new setting will be required for other grades of paper If Kodak Polycontrast paper is used the controller will automatically adjust for filters and the inherent paper speed change using only one setting and will also compensate for filter pack changes when printing color o ELECTRONIC EXPERIMENTER S HANDBOOK An easy to build locator that detects buried metal objects at depths of 6 inches BY JOE A ROLF OST inexpensive metal loca tors are heterodyne types where the output frequencies of a fixed and variable oscillator beat The fixed frequency oscillator serves as a reference while the other oscil lator has a sensing loop that changes its frequency when brought near met al The resulting heterodyne differ ence frequency between the two oscil lator signals is amplified and fed to a speaker or meter The low cost metal locator de scribed here is a heterodyne unit But it is less expensive and easier to build than most because it can
285. sssssss 17 Text File Editor and manual sssssoeee 10 I O drivers on cassette BASIC patches 10 SCOPE DATA SERIES 200 PRINTERS Non impact printers using electro sensitive paper Up to 80 char line 120 char sec optional 240 char sec Prints 96 character set uppercase forms in two sizes 10 char in 6 lines in Has print densi ty control paper out alarm uses 8 2 in wide paper on 300 ft roll Interfaces to RS 232 20 mA and TTL serial ports or parallel TTL 200 RO Receive only version n 1595 200 KSR Keyboard send receive version 1895 256 character FIFO buffer option for 1200 baud 364 Expanded character set option 0 00 295 300 baud acoustic coupler option 00 275 Compressed character option 132 char line 16 5 chance n C eee 150 SHARP amp ASSOCIATES SELECTRIC CONVERSION KITS Converts IBM Selectric or Selectric I typewriter for use as I O terminal unit remains usable as type writer Includes solenoids and opto electronic key sensors SK 1 Conversion hardware and manual requires 10 parallel 1 O lines for interface 12 V power supply rrr ME PRIM 148 SK 2 Same with 12 V supply and TTL compatibility BUILD YOUR 2 6 Ww TROUBLE x FREE LOSCOPE Engineered by Heath Co and Manufactured for use by RCA Institutes Ideal and inexpensive for Professional Service Technicians Students and Experimenters A five inch scope designed f
286. sulated stand offs The metal chassis must be floating not connected to input or output The emitter resistors for transistors Q5 through Q70 are made of 14 inch lengths of 22 wire It is important that the lengths of the resistors be as nearly the same as possible sothat the transistors share equal amounts of the current The secondary of 72 is at 117 volts ac so use care in routing the leads Dress leads away from the heat sink and use wire rated at 105 C The leads from the inverter to the battery through the rear of the case may carry as much as 18 amperes so use heavy gauge wire or lengths of line cord with both leads in parallel for each side If the connection is very long use four parallel wires for each side to keep the voltage drop in the leads to less than 0 5 volt When assembly is complete check again to make sure thereis no connec tion between the case and the input or output Testing With the cover off set Hi and R71 to their mid positions Con nect the battery leads to a high current 12 volt source vehicle bat tery Turn the inverter on and note that the meter indicates less than 2 A drain If this is not the case im mediately turn off the unit and deter mine the reason 69 e R4 9 e R2 9 Ci e eca e RI4 e e R e e R3 e9 1 e R5 e9 et RIS ey I e ICi e D2 e C9 ob3 e ca ea M v
287. supplies the various operat ing voltages at the required currents to all devices coupled to the bus Bus Structure Essentially the bus consists of a number of conductors POWER SUPPLY APPLICABLE AN usually copper traces on a large PC board with plug in connectors at tached at intervals This allows various additional module boards to be plugged in anywhere along the bus Although quite a few computers have their own bus system the most common one is the Altair bus invented by MITS for use in the original Altair computer some manufacturers call it the S 100 bus because there are 100 pins on each bus connector There are current ly available over 150 modules from about 40 manufacturers that can plug directly into this bus The Motorola EX ORcisor and SWTP 6800 busses are also supported by products of more than one manufacturer but not to the same degree Modules and Expansion The great advantage of a bus system is that many devices can be designed to plug into the bus and thus expand the comput ers versatility Most of these plug in modules are RAM and ROM memory boards of all sizes and speeds Among the many dozens of plug ins currently available you will find such useful ones as cassette interfaces video display modules multi port boards and even a vocal input that enables the user to speak to h s computer Cassette interfaces generate audio tones usually one frequency for each
288. t in the assembly is the construction of the heat sink To keep the operating temperature below 100 C the heat sink must have more than 500 square inches of area Details of the construc tion are shown in Fig 2 Note that there are nine sections of 1 32 thick aluminum in the heat sink with holes drilled to mount the six power transis tors After drilling the holes for the trans istors remove the burrs The transis tors share common mounting holes with three transistors on one side of the sink and three on the other Use silicone grease under the transistors to insure intimate thermal contact with the heat sink The transistor cases are not insulated from the sink as all collectors are connected in parallel The heat sink is insulated from the metal case by four insulated stand offs Do not try to use a smaller heat sink or you will run the risk of damaging the transistors The remainder of the circuit is mounted on a pc board Fig 3 Note that the cases of diodes D10 and D11 are actually thermally bonded to the heat sink The cutout in the board al lows the diodes to contact the heat sink with silicone grease to insure the contact Transistors Q3 and Q4 are also mounted so they touch the heat sink Their collectors are at the same potential as those of the power trans istors Drill suitable holes to attach the pc board to the lips on one end of the heat sink After selecting a chassis mount the heat sink on four in
289. t A which are applied to pin 4 of iC5 This causes C5 to count down two steps The BCD to decimal de coder C4 takes the output of C5 and causes the lit LED to move two posi tions toward the A end If player A is not quite as fast and pushes his button during period 13 the output of C2C and the pulse at Fig 5 Power supply delivers two different voltages for the project 3 e 1C7C fp i A Fig 3 Player circuits are identical Outputs of one shot circuits are compared with timing pulses on X Y and Z V C24 47 pF B SPKR C26 A 47pF CI9 c27 C235 C22 ur uF ur Oly F Fig 4 Optional sound output circuit is two gated tone burst generators each having a different frequency to create separate sounds for players ELECTRONIC EXPERIMENTER S HANDBOOK Fig 6 Foil patterns for the double sided pe hoard are shown at right and below point X are applied to AND gate C3B Then only one pulse appears at point A and the lit LED advances only one position toward A When player A tries to anticipate the GO light and presses his button too 1978 Edition e o O 00O o 0 E Qo ooacoe 90000000088 oo O O amp E O o9 ecceces 000 o 909000086 ie e TUG OF WAR 900806 o o soon the pulses from C2C and point Z are applied to AND gate C7B and the output at point B causes the counter to go in the other direction The circuit for player B operat
290. t levels Regulation can be observed by using various values of load resistors on the supplies The low voltage supplies should regulate to within about 0 2 or better from zero to full load The current limiting circuit will hoid the output current to the preadjusted level regardless of the value of the load ELECTRONIC EXPERIMENTER S HANDBOOK re gt br f tae g aie Y INCOME OR A CAREER Career opportunities are opening up fast for the man trained in communications The field of communications is bursting out al over In Citi zens Band alone class D licenses grew from 1 to over 2 6 million in 1975 and the FCC projects about 15 million U S CB ers by 1979 That means a lot of service and maintenance jobs and NRI can train you at home to fill one of the countless career jobs available in design instal lation and maintenance of communications equipment otart training now the NRI Way to get your all important FCC Radiotelephone License and qualify for one of these Openings Learn on your own 400 channel digitally synthe sized VHF transceiver The NRI Complete Communi cations Course teaches you at home to service and adjust all types of two way radio equip ment including CB using the one unit that is best equipped to train you fo CB Commer cial and Amateur communica t ons a digitally synthesized 400 channel VHF transceiver 1978 Edition and AC power supply This 2 meter
291. t of the toy or novelty class Alternatively by adding a few more components you can use the same chip to tune in the WWV or CHU time signal Stations In fact there are dozens of specialized radio applications in which this new IC can be used Simplest AM Receiver Perhaps the simplest application for the ZN414 is the AM receiver shown schematically in Fig 1 With a circuit as simple as this it is al most impossible for anything to go wrong In fact a prototype receiver worked beautifully the first crack out of the barrel Local stations came in with superb clarity and adequate volume through the headphone Because of the outstanding action of the C s built in age circuit tuning the re ceiver was a bit unusual You expect to hear a jumble of stations But when you tune to the frequency of any one station the station s carrier affects the agc so to 1978 Edition PROJECTS BY CARL C DRUMELIER tal sensitivity drops enough to eliminate off frequency stations Time Signal Receiver With only a few more parts than needed for the AM receiver you can build a 2 5 MHz time signal only receiver to pick up WWV The schematic for the receiver is shown in Fig 2 With this circuit a 15 ft length of wire serving as the antenna provided good reception of the WWV signal Coils L2 and and L4 are standard 30 wH units with adjustable ferrite cores For L2 the coil must be tapped 10 turns from the bottom to provide a tie on point
292. t supply Bat Charging 12 14hr Size HWD 1 75 x 5 63 x 775 4 45 x 14 30x 19 69cm Weight Less than 1 51b 0 68 Kg w batteries CONTINENTAL SPECIALTIES CORPORATION 70 Fulton Terrace Box 1942 New Haven CT 06509 203 624 3103 TWX 710 465 1227 West Coast 351 California St San Francisco CA 94104 415 421 8872 TWX 910 372 7992 CIRCLE NO 4 ON FREE INFORMATION CARD 13 ERE IS a power supply package incorporating a number of fea tures which make tt not only unique but extremely useful First of all the package includes three separate power supplies Two of these are iden tical and are designed to supply inde pendent operating voltages for trans istor and integrated circuits one can be used as the positive supply the other negative Each has an output capability of up to 15 volts at 0 75 am pere and the adjustable output vol tage is regulated to 0 1 or better These two supplies are completely iso lated from one another which makes it possible to stack them for higher output voltage or to operate them at different ground levels Parallel oper ation of the two supplies is not re commended since the very least vol tage difference between them causes undesirable interaction between the two The supplies are generously over rated and can be operated at maximum capacity on a continuous basis without overheating The third supply is similar to the other two except that it has a higher Output voltage and curr
293. t to speed up the process The vco finally locks and the beat fre quency is zero The low pass filter is an important factor in controlling the capture range If the vco is too far away from the signal the beat frequency will be too high to pass through the filter and the signal is out of the capture band Once lock has been achieved the filter no longer restricts the PLL It can track a signal well past the capture band being restricted only by the out put range of the phase comparator However the filter does limit the speed at which the PLL can track If the signal frequency changes too rapidly the PLL can become un locked The low pass filter is an engineering trade off On one hand it restricts the capture band and reduces tracking speed but without it the PLL would have great difficulty locking The filter supplies the PLL with a short term memory of where it was with re spect to the signal providing a sort of fly wheel effect It also memorizes the rate of change of the signal fre quency Even if the signal should drop intoa noise level for several cycles the filter will continue to shift the vco at the same rate until it picks up the signal again This produces a high noise immunity and locking stability The 560 Family The most popular family of PLL IC s is the Signetics 560 series The table lists the important specifications for various units in the series The first three are high frequency devic
294. t wired TRE dune BEAD PaaS PERSCI 1070 DISKETTE INTELLIGENT CONTROLLER Diskette drive controller with 8080 MPU intelli gence built in Communicates by file name as sumes all housekeeping functions usually per formed by the computer s MPU allows data transfer between diskette and MPU interface or optional RS 232 interface ROM options allow copy data transfer between diskettes Requires interface Wired with Model 70 single drive 1195 Wired with Model 270 dual drive 00 1575 PROCESSOR TECHNOLOGY HELIOS li DISK SYSTEM Dual drive diskette system with DOS power supply Altair bus controller board case cables documen tation system diskette with DOS and FOCAL inter preter on disk Capacity 386k bytes per diskette Over 750k per system capacity can be raised to 1 5 M bytes with additional dual drive Kit wired m een aM S 1895 92295 BASIC on diskette 0 cccccceccescceccesecceess n 50 PROKOTRONICS PTR IIPAPER TAPE READER High speed optical tape reader no moving parts tape is fed hand over hand Requires parallel in terface user supplied light source Kit wired MORE ee TEET E 54 68 PTR M Motorized version of above low voltage mo tor can be controlled by computer allowing start stop and reverse feed under software control user supplied light source required Wired 115 RADIO SHACK ARCHER KEYBOARD ENCO
295. table one shot mode Basically a E 1 trigger input causes an output pulse ZAA BOG whose width is determined by the value of a timing resistor and capacitor ti o 99 b o di e t e o 9 How E PARTS LIST ac ee 1 B1 B4 1 2 volt C cells hd mE v gt 9 C1 C14 C16 C22 C24 C28 0 1 pF 25 V S d s disc capacitor eo e 9 6 o C15 C23 0 0 pF 25 V disc capacitor z D IC 1 C9 NES55V IC timer or equiv o n LEDI LEDI5 TIL 32 LED or equiv u QI Q2 2N5129 or equiv Ed The following resistors are 4 W 10 toler ance unless otherwise noted R R3 R5 R7 R20 R22 R24 R26 c S R28 100 000 ohm H o R2 R4 R6 R8 470 000 ohm e R9 R 12 R30 R34 220 ohm E e e T S Y ee RI3 R19 10 000 ohm gt S R21 86 000 ohm 255 i G v 9 R23 R25 390 000 ohm o T e y 32 R27 68 000 ohm o e m m 3 g R29 220 000 ohm one eg E a os a R35 2 megohm 2 W linear taper pot 764 9 baa 2 a e e ars SI S p s t momentary pushbutton switch 52 e E S v normally open o i ON 3 d T m S 3 S2 S3 S p 3 section 12 pos rotary switch T eo v REV o3 S4 S5 S6 Momentary pushbutton switch A o CAD es S P 3 5 c o rau open Poly Paks 92CU1749 spec it 4 7 eno 2 E S7 S p s t switch a e 9 d p J1 Miniature phone jack if Sound Option is gt E a e Z e EI e e used O Cj e 3 Misc 4 x 2V4 x 24
296. table listening level Then advance the sensitivity control until LED starts to flicker Avoid bright peaks on the LED The music should sound more accented with a greater dynamic range Operate the depth control to obtain the desired amount of expansion To be sure ev erything is working turn off the com pander and note how much flatter the music sounds To check compression place S7 on COMPRESS and the sensitivity and depth controls to maximum Turn up the volume You should note that the audio output does not rise above the preset level Adjust both controls to obtain the best output At some low listening levels there may not be quite enough signal to drive the compander properly This produces a breathing effect which can be remedied by turning up the lis tening level or turning down the depth control This effect may also occur if the calibration controls are not set high enough There is no such thing as the op timum amount of expansion Some recordings require less than others However most will benefit from the extended dynamic range Fig 3 If you have separate preamp and power amplifier use hookup at A For integrated amplifier use B Both are for one channel only 25 26 Circuits happen Faster and E with Super Strip s s J as 9 P ae j i a q As little as 49 m Now whenever you d like to give a circuit a try you can build it up nearly
297. tacts close In the opposite direction powering the second lamp and extinguishing the first Dc power for driving the circuit is obtained by rectifying the ac coming from the generator actually an alter nator through D1 and filtering it with C3 Since the output of the generator R2 100K 38 often contains spikes with amplitudes in the 15 to 20 volt range zener diode D2 is used to protect C1 from over voltage damage Diode D3 connected across the winding of K1 protects C1 from the inductive kick back emf that re sults when power is removed sud denly from the relay s coil The circuit does not use or need a power switch Power is applied and removed from the circuit simply by engaging and disengaging the generator Construction Since the circuit is very simple it can be assembled ona printed circuit or a perforated board Parts placement is not critical whichever method of assembly you choose Relay K1 should be a6 volt unit with a coil resistance of about 500 ohms Its contacts should be rated for at least 1 ampere at 6 volts Bolt the relay di rectly to the circuit board Then after making all necessary connections to its coil and contacts use silicone rub ber cement to anchor its plastic cover to the board The two 63 auto backup lights used for 1 and 2 should be housed in 2Vo in 6 35 cm diameter red lensed holders such as the Pathfinder 667 red taillight assemblies The lights
298. ted and on the board components PARTS LIST B1 9 volt transistor battery C 1 500 pF ceramic capacitor C2 365 pF miniature variable capacitor C 3 47 pF ceramic capacitor C4 120 pF ceramic capacitor J Phono jack See text P Phono plug QI 2N3819 or HEP 802 Motorola field effect transistor S1 Spst slide or toggle switch Misc 3 4 x 214 x 158 utility box per forated phenolic board and solder clips No 32 enameled wire for L1 24 outer diameter aluminum tubing or broom handle cut to 36 length coil form for L see text 36 Belden No 8411 mi crophone cable control knob 6 machine hardware spacers battery holder phone jack and plug for sensing coil cable optional solder solder lug etc 43 GROUND LUG SI Fig 3 Photo of prototype showing how the boards and components go in to the chassis Drill two Ve in diameter holes and mount the bottom half of the utility box to the handle you plan to use for your metal locator For the handle you can use either 4 in outer diameter aluminum tubing or an old broom handle Whichever you choose cut it to a length of 36 in and wrap the top with several layers of electrical tape to provide a comfortable grip Then mount the bottom half of the utility box to the aluminum tubing with sheet metal screws wood screws if you are using a broom handle as shown in Fig 4 An 8 in by 6 in lid for a plastic freezer contain
299. th 16 key hex keypad six digit hex LED display 8k RAM memory expandable to 64k 25 A power supply ROM monitor editor and I O TTY RS 232 and Kansas City standard cassette interfaces In fan cooled cabinet with 13 slot motherboard also accepts Motorola EXORci sor cards Available with extra I O and bus connec tions at front panel M68b Wired 1878 MICRO 68 6800 MPU with hex keypad and display 128 bytes of RAM 512 byte ROM monitor editor power sup ELECTRONIC EXPERIMENTER S HANDBOOK ply one I O port In wood plexiglass cabinet with room for 640 words additional ROM other options below M68C Wired 495 X68C Expanded version with 8k RAM 3 5 A power supply additional ROM for TTY TTY RS 232 and cassette interface expansion cabinet 1186 RAMB8K 8k static memory 390 RAMAK 4k static memory 290 R6810 Additional 128 byte RAM for Micro 68 6 PEB1 16k PROM board for 7641 3624 PROMs 240 PROM512 512 byte PROM for above programming available 24 PEB2 512 byte PROM board for Micro 68 18 PROM256 256 byte PROM for above programming available 10 MB6830L7 MIK bug ROM for TTY 29 TTy4 TTY PROM 24 GP1 General purpose prototyping board 30 TCC3 O for Byte standard cassette RS 232 termi nal and TTY irequires TTY4 or MIK bug ROM 129 TVA 1 Video interface and TV adapter for 29 line 30 character display Includes keyboard input and HS 232 interface For X68c
300. that you could have paid a lot more than 69 95 for possibly receiving a lot less But this one s from Sabtronics specialists in digital technology Maybe you should order yours before you turn the page ponant a Made in U S A sabtronics INTERNATIONAL INC e PO Box 64683 Dalias Texas 75206 214 369 7310 GUARANTEE Ue Ola rane UE UE To Sabtronics International Inc EH78 l DMM kit for 10 days If you re not satisfied PO Box 64683 Dallas TX 75206 j return it unassembled for a full refund of i purchase price Please send me ___ Sabtronics Model 2000 DMM kit s at 69 95 each m subtotal SPECIFICATIONS DC volts in 5 ranges 100uV to 1000V Shipping and handling 5 00 per unit subtotal AC volts in 5 ranges 100uV to 1000V Texas Residents Add Sales Tax___ o o DC current in 6 ranges 100nA to 2A TOTAL enclosed CO AC current in 6 ranges 100nA to 2A l umet u l Resistance 0 192 to 2OMQ in 6 ranges i AC frequency response 40Hz to 50KHz Street Aadress NEN 9mm 36 LED display i Input impedance 10M0 City ___ __ Cid size E W x 6 5 D x 3 H i 1 203W x 165D x 76H mm State lip i USA only Canada 6 50 Ail other countries 10 00 surface mail Power requirements 4 C cells not included ku msc u e ss ee ee e e L m a a dd 1978 Edition CIRCLE NO 22 ON FREE INFORMATION
301. the tracks to increase Conversely de pressing S2 causes the output voltage to decrease And pressing stop switch S3 causes the output voltage to im mediately drop to zero A visual indication of the speed at which the train is moving is obtained by observing how bright the light is from lamps 1 3 One of these lamps is optionally inside each pushbutton switch The greater the track voltage the faster the train is moving on the tracks and the brighter the lamps The three diode current limiter composed of D5 D7 holds the current being fed to the tracks to approxi mately 1 ampere Hence the circuit is protected in the event the train tracks should accidentally be shorted to each other Construction Owing to the simplic ity of the circuit the entire controller except for T1 and the switches can be mounted on a piece of perforated board with the aid of push in solder 76 terminals and sockets for C1 and C2 Series pass transistor Q7 must be mounted in an aluminum heat sink with about 9 sq in 58 sq cm of radiat ing area You can mount the circuit board as sembly and transformer in any suita ble enclosure The control switches and potentiometer are best mounted on the top of the enclosure while out put jacks J7 and J2 are more conve niently located on the rear of the en closure as is the exit hole strain re lieved or rubber grommet lined for the line cord In Use The upper voltage limit to th
302. the more important factors that affect economy is engine timing In addition proper timing is required on all automobile engines so that exhaust emissions do not exceed allowable limits Timing changes for a variety of reasons As the parts of an engine wear the timing tends to become re tarded If ignition points are replaced timing is also disturbed Furthermore itis virtuallyimpossible to set the point gap exactly the same as it was when the timing was last set Using a dwell meter is a far more accurate method of setting point gap than using a feeler gauge but even this will not guarantee proper ignition timing The fact is the best way to check ignition timing is with a timing light The timing light described here can be built for only a few dollars Yet it is designed to perform as well as a commercial unit costing 25 or more Its light output is bright enough to use 1978 Edition BY ANTHONY CARISTI under conditions of bright daylight and it is battery powered from the car s battery to make it independent of the ac line About the Circuit The heart of the timing light s circuit Fig 1 is dc to dc converter transformer TI It alternately switches current between transistors Q1 and Q2 while stepping up the bat tery potential to about 125 volts A fer rite pot core was chosen for this cir cuit to keep down project size and cost The primary winding of T1 wound around the pot core is done by the bif
303. the screen Using the same tech nique that was used to load the flashing LED program load Program 2 the video test software Once loaded depress the RUN Switch and note that the CRT moni tor should synchronize to the ElIf I sync signals and display a stable raster with a cloud like display near the top of the raster This cloud like layer is actually the program you just inserted The 1 s appear as bright boxes while the O s are represented as dark boxes Refer to POPULAR ELECTRONICS July 1977 issue for further details on video pro gramming including how to animate the display Adjust the CRT monitor brightness and contrast controls for the best pic ture If the sync appears to be unstable or there does not seem to be enough contrast one or two resistors in the EIf 1I might require a different value to in crease or decrease the sync level For instance resistor H34 s value can be changed To make changes in the video level H35 can be altered Neither resis tor affects circuit operation just the level of its associated signal source Programming Although learning to program the 1802 is not very difficult training and practice are required The reader is urged to purchase the COS MAC User s Manual which is available from your local RCA Distributor or from the source listed in the Parts List The reader is also urged to read the four Build the COSMAC Elf articles that ap peared in POPULAR ELECTRONICS They
304. tibn operaror and VAL AND STR functions e convert between strings cnd numbers Extended ALTAIR BASIC cliows integer single and double precision viables automatis line numbering and rehumbering user defined string functions PRINT USING for for matted output and a powerful ECI com mand fcr editing program fies during or atter entry Bended statemenss and commoanics include IF THEN zLSE LIST ana DELETE progran lines SWAP varichbes and tace On and Off for debugging Disk AL AIR BASIC has cli the features of Extended BASIC with the cdditionc capa bility to maintain sequential and rancom access disk files Utilities are provided for fermatting disks and priming directer es ir all versions of ALTAIR BASIC you get the ease ord efficiency of BASIC for the solution ot real world problems eei feo il an assembly larguage develop ment system for the Altar 8800b ircludes system monitor text editor assembler and debug Afford ability Prices for the Stair 88006 start at 840 00 for a dt and 4100 20 for an assembled ur tidi documentation included for a complete listing of prices ali Altair prodascte and a free bro chure contac MITS Inc t 2450 Alamo SE Albuquerque f M 87106 505 243 7824 LAT ae H I g fo w TU Clockwise from top left Impact Printer CPU 9 Video Monitor Cassette Storage System with Four Drives Ke
305. to do this with the sensing loop far away from any metal objects Now sweep the sens ing loop near to a metal object the tone should re occur Thesensing lo p described above is most useful for general purpose work but other sensing coil configurations Fig 5 The sensing coil is wound on plastic free zer container lid that is stiffened with Bakelite or phenolic Phono jack is used to connect loop to oscillator cable ese aie Ron SU oss Fig 4 Attach bottom half of box to handle and mount the top half as shown can be built for specific applications A round 6 in diameter plastic con tainer lid with 25 turns of enameled wire can be used for exploring smaller areas while a ferrite antenna coil de signed for use in transistor radios in side a length of plastic tubing will pro vide a wand type sensor that is useful for locating ducts studs and pipes in walls Whichever sensor you plan to use it is important that the cable be tween loop and utility box be less than 36 in long While using the metal locator you will discover that the audible indica tion you get is proportional to the size of the object being sensed its depth below the surface of the soil and soil condition An object the size of a soup canatadepth of 6in is easily detected in dry soil but at a lesser depth in wet soil With practice it is possible to de termine the size and depth of an object a good thing to know be
306. to drive the phase lock The 565 provides a method of limit ing the locking range A tap on an in ternal voltage divider is used as a ref erence output pin 6 This voltage is the same as the output voltage pin 7 when F is equal to the incoming signal Connecting a resistor between pins 6 and 7 differentially loads the Output without changing the dc level or shifting the vco A resistance change from 25 000 ohms to zero be tween these points will shift the lock ing range from 60 to 20 Since the output is loaded one can expect a corresponding decrease in the level of the output signal 51 1000 INPUT MILLIVOLTS p p NORMALIZED LOCK RANGE HISTORY OF PHASE LOCKED LOOPS In 1932 a group of British physicists Was Working on a new method af radio reception to compete with the superheteradyne system This new ap proach would require only ona tuned circuit and would have greater fidelity and selectivity thanthe superhat circuit The theory was deceptively simpia When an r f oscillator and an incaming signal are mixed at the same phase and frequency the output product will be perfect audio reproduction of tha transmitted modulation An adjacent carrier 20 kHz away will be demod ulated as a 20 kHz signa and could cas ily be filtered out of tne desired audio The system was constructed using a simple untuned r f amplifier to feed the mixer The results were as tonishing perfect receplian with no adja
307. to the IC Whenever this signal is supplied to the IC it sends a signal to the base of O3 which turns on limiting indicator 7 Instead of an IC the high voltage supply uses transistors throughout Fig 2 The voltage reference is pro vided by zener diode D2 Comparison of the reference to the output level from R15 is made by Q2 The current output is monitored by Q4 with feed back determined by R17 lf 04 is turned on Q5 is turned on to change the output through Q3 and also to e 1 Vata amp Li irr wi Wh 1 Ade ELECTRONIC EXPERIMENTER S HANDBOOK Cl vy L C3 IOOpF QI HEPTIS R7 IK Q2 HEP7O9 fy js 22K R9 l IK pae cL M MM D RI Ri2 250K IM VOLT LIMIT Rt RI 7 4700 IOK OUTPUT VOLTAGE LEVEL NOTE DO NOT USE CHASSIS AS COMMON turn on Q6 and energize the indicator light Voltage output is monitored by Q7 with feedback from R16 When Q7 turns on Q4 turns on as for current limiting Conventional transformer and full wave rectifier circuits are used to power each supply as shown in Fig 3 The individual transformers provide complete isolation between the supplies Note that each supply is in dependent and their commons are not connected to chassis ground Construction Any type of enclosure can be used for the three way supply In this case a Bud CU 7127 cabinet was used and the bottom plate was constructed of s aluminum drilled for the three large capacitors The power su
308. to the same points in Figs 1 and 2 The X marks in the receiver schematics indicate that with the modifications in place the phones power switches and battery must be disconnected ABOUT THE ZN414 Imagine an iC that has a very high input impedance three r f amplifiers and tran sistor detector stage all in one tiny TO 18 package with only three leads See ilius tration What we have just described is a versatile linear IC called the ZN414 made by Ferranti Electronic Components Divi sion in Britain Now available in the U S this IC offers the hobbyist and experiment er a new approach to radio experimenta tion The ZN414 is housed in just about the smallest package you are likely to see for transistors let alone IC s its three iead format makes the device a cinch to work with Those three leads are for the input Output and a ground that is common to both Although the circuit configuration is unknown to us we do know that it contains 10 transistors A list of its technical specifications re veals just how versatile is the ZN414 The circuit is designed to amplify incoming sig nals ranging in frequency from 150 kHz to 3 MHz Its detector responds to AM Signals within that range The IC has a remarkable 62 PHONES Just about any silicon transistor npn variety can be used in the voltage regulator circuit in Fig 3 Use the poten tiometer to adjust the voltage between pins 1 and 3 of the ZN414 to rough
309. tor R4 18 000 ohm 2 watt resistor gi S1 Spst switch a S2 3 pole 6 position rotary switch Mal lory 3236J or similar SO1 Molded transistor socket T1 12 volt 300 mA filament transformer Radio Shack 273 1385 modified per text Misc Plastic case Radio Shack 270 231 Insulated miniature alligator clips red green and yellow Radio Shack 270 378 knob with pointer line cord mounting hardware press on type etc Fig 1 Transistor being tested is plugged into SOI or connected to color coded alligator clips o or o NS ee then be spaced three on each side on 38 in centers Wind 46 turns of 34 enamelled wire around the original core There is enough room to do this although it will take a little patience Be sure that the new winding is wound in the same direction as the 12 volt winding already on the transformer to ensure correct phasing Don t scrape the enamel off the wire If you should wind the new secondary the wrong AC LINE 1 AC LINE RED _ 2 Y e SI amp 9 4 YEL 2 x e 2 3 GRN 2 2 3 2 LED 2 K LEDI A Jr Jr 02 9 w 01 9 D3 RI Fig 2 Foil pattern for S2 main pe board is at left GS Pa with component layout rE c RRE R E o Oe i at right Foil pattern Q2 he B al above is for rotary switch Ce ELECTRONIC EXPERIMENTER S HANDBOOK way It is easier to route the ends to t
310. tput Few computers have all of these facili ties built in but all computers allow the use of peripheral equipment for these and other purposes Terminals The easiest way to com municate with a computer is via a type writer like keyboard with the computer s output visible on a CRT screen or on pa per If the computer has a video inter face built in a separate keyboard is the only thing which need be added If not it takes a CRT terminal or printing terminal Teletypes are popular for this contain ing keyboard and output CRT terminals are faster quieter and don t waste pa per printing terminals leave a perma nent record which is helpful in debug ging programs and in using the comput ers output Elaborate systems may have both a CRT terminal for quick com munication between operator and com puter and a separate printer which can be switched in when required Mass Storage Long programs like assemblers and BASIC interpreters can be entered from the keyboard but since it can take about 6000 keystrokes to load an assembler and 24 000 strokes to enter an interpreter plus the time needed to search back and find where the inevitable errors crept in this is hardly practical especially for programs which are used frequently Most such programs are therefore delivered on either punched paper tape audio cas settes or magnetic floppy disks which can be read into the machine in minutes or seconds But to read them
311. transceiver gives you Power On training Then we help you get your FCC Ama teur License with special instructions so that you can go on the air More know how for your dollar The complete program includes 48 lessons 9 special reference texts and 10 training kits Included are your own elec tronics Discovery Lab a new Antenna Applications Lab an Optical Transmission System CMOS Digital Frequency Counter and TVOM The course covers AM and FM Transmission Systems Radar Principles Marine Aircraft and Digital Electronics and Mobile Communications You must earn your first class radio telephone FCC hcense Or you get your money back CB Specialist Course also available NRI offers a specialized course in CB Servicing You get 37 lessons 8 reference texts your own CB transceiver AC power supply and multimeter for hands on training Also included are 14 coaching units to make it easy to get your commercial radiotele phone FCC license enabl Ing you to test install and service com munications equipment Widest choice of courses with Quadraphonic Audio and Color TV Servicing NRI offers five TV Audio ser vicing courses as well as career courses in Digital Com puter Electronics Marine and Aircraft Electronics Mobile Communications and more Over a Million have enrolled with NRI send for the free NRI catalog and discover why more than a mil ion people like yourself have
312. ts four 5 way binding posts base plate all hardware 10 minute assembly with pliers and screwdriver points 8 W x 9 8 L x 1 4 H 6 L x 4 W x 1 4 H 152 x 102 x 34mm 203 x 248 x 35mm 1 75 Ib 7 oz 20 Kg Price 15 95 79 Kg Price 79 95 PB 104 3060 solderless tie points thirty two 14 pin DIP capacity 472 five point termi nals plus 14 bus lines of 50 tie Now breadboard in any direction With EXPERIMENTOR sockets the breadboarding system that gives you more flexibility for less dollars EXPERIMENTOR 300 Arrange EXPERIMENTOR AC gocce wade Thaan f il DIP f sockets to suit your circuit t eere dup DRESD instead of rearranging your peripheral Top View circuit to fit the breadboard microprocessor IC s 6 0 x 2 1 overall Discover the ease and convenience of SA f solderless breadboarding CSC EXPERIMENTOR 600 9 i EXPERIMENTOR sockets let you 6 centers perfect p design assemble and modify circuits as fast as you can push in or pull out for microprocessors clock chips RAM s ROM s and PROM s Bottom View us put H 6 o X 2 4 overall Se Just 10 95 Large Capacity Large sockets have d c ctl 550 solderless tie points 94 five point SPECIFICATIONS TIE POINTS terminals plus two 40 point bus Strips Center 5 Tie Points Bus Model Length Width Channei Terminalst Stripst Price 300 60 p 3 94 470 2 80 9 95 e Full Fan Out A CSC
313. ts family of sup port devices Chassis motherboard memory card with 4k bytes of eight bit static RAM serial 20 mA TTY RS 232 interface card power supply crystal controlled clock for baud rates from 110 to 1200 6820 peripheral interface adapter PIA ROM stored mini operating system features tape ioad dump routine memory and register examine and or change function and execute users program command Documentation package includes Moto OMPUTER Sum 6800 Ei rola 6800 Programming Manual plus SWTP 200 page notebook diagnostic and game programs and application to join Motorola 6800 User Group All boards are plug in type and contain on board voltage regulators Any combination of up to seven serial parallei interface boards may be plugged in Kit Sone DOSS MP M 4k memory board with 2k esc 65 2k expansion kit for MP M da S35 MP 8M 8k memory e eroe Praet T YN 250 MP L General purpose parallel interface 35 MP S General purpose serial interface 35 MP T Interrupt ttmerboard s 40 STM SYSTEMS BABY 1 6502 MPU portable system supplied in attache case Includes 62 key keyboard 1200 baud cas sette interface programmable to simulate any of the interfaces presently on the market with stand ard and reverse polarity cables video interface dis playing 16 lines by 32 characters displays ASCII 128 character upper and lowercase plus low
314. ts own shopping list Evaluate the stock market set up gambling and probability programs EXPLORE INTERFACE AGE MAGAZINE READ INTERFACE AGE FOR THE LATEST ON NEW PRODUCT INFORMATIO ANC TECHNICAL BREAKTHROUGHS May s issue included inside the FLOPPY Rom a vinyl record which is played on a conventional phonograph to enter this month s program in your computer En E es NND NND NND NND ND ED a eee ee ee ee O8 ORDER YOUR SUBSCRIPTION NOW 12 Monthly Issues 14 U S 16 Canada Mexico 24 International Name Address _ City Acct No ARTICLES RANGE FROM THE FUNDAMENTALS OF COMPUTERS TO LANGUAGES AND SYSTEM DESIGN APPLICATIONS INCLUDE BOTH PROFESSIONAL AND NON woes 1978 Edition Signature Check or M o U s funds drawn on U S bank State zs pe 3 Visa Card M C Exp Date Make checks payable to INTERFACE AGE Magazine P O Box 1234 Cerritos CA 90701 85 they were written for BASIC and other high level language programs can run on any machine programmed with that language Minor changes may be nec essary since there are several slightly different versions of BASIC but these changes are easily learned Peripherals To use such languages a computer must have a means of en tering long assembler and high level language programs storing them when its power is off a means of entering and storing the user s own programs and a means of seeing the computer s ou
315. tstrap loader All buffering CPU dependencies and housekeeping circuitry Input Output Card Four 8 bit parallel input ports Four 8 bit parallel output ports Motherboard Prices for standard systems including the above features start at 475 for Z 80 425 for 8080 or 6800 375 for 6500 More Many options peripherals expansion capabilities and accessories are already available They include rapid computer controlled cas sette drives for mass storage printers color graphics interfaces memory I O monitors prom boards multiple power supplies prototyping cards and others Software packages include BASICs Assemblers Disassemblers Text Editors games ham radio applications software training cassettes system packages and more even biorhythm Sounds neat now what Now that you know a little about who we are and what we re doing we need to know more about you n order for us to get more information to you please take a few seconds and fill in our mailing list coupon We think you ll be pleased with what you get back CIRCLE NO 7 QN FREE INFORMATION CARD
316. tware support among the most pop ular Each processor has some advan tages over all the others or there wouldn t be so many The power of a processor is in its built in instruction set The more instruc tions and the more each can do the more powerful the processor The in struction set of each processor is unique to that particular type and a machine language program written for one type will not work on another as their instruc tion sets are not the same About the only exceptions are the 8080 and Z 80 The 8080 has 78 in structions The newer Z 80 uses the 8080 s 78 instructions plus 80 more So most 8080 software will run on a Z 80 but because of the extra instructions compatibility only goes one way a ie NUNT h ay S sate panei MIU ee en eee n a M z ie t aa stat nh m M Qu suena o a Sa DS Aer TEN MER viri Soe ae J x us m e Rn n ME Cre IE e e Ist P ATI IET Coco NA A basic microprocessor is shown in Fig 2 This single IC contains a variety of specialized circuits too complex to cover in this article but they follow the logic shown in Fig 2 Essentially the MPU accepts the in coming data processes it in accordance with the software selected portions of the built in instruction set then passes the resulting data down the data bus along with the pertinent address require ments and control sometimes called handshake signals Since each item connected to the bus structu
317. uF GND cured to a pair of wood side supports us ing suitable wood screws passed through the two holes on each of the narrow sides of the board Once the board has been mounted and all the passive components and IC sockets are in place the IC s have to be installed As many of the IC s are CMOS types extra care must be taken in both han dling and installing them Hold the IC s by the case edges not the pins Keep one hand on the board foil pattern when installing the IC s to prevent static build up then install the IC s in their proper places using the component placement guide of Fig 8 Make sure that you ob serve all pin 1 designators Other than installing bus connectors the EIf I1 should now be assembled and ready for testing However before turn ing on the power recheck the board for correct installation of all components Then check to see if there are short cir 96 RI OPTIONAL EE A18 7805 5V Fig 7 The power supply except for e the transformer IOuF is mounted on the Elf II pc board GND cuits between any closely spaced pc foil traces Testing There are two tests that can be made to check Elf Il operation The first uses the flashing of the Q1 LED to check computer operation while the second test checks out video operation Program 1 listed in an accompanying table is the computer test Before en tering this program the Elf ll must be powered To do this connect
318. ude you already have just put your hands and your head to work with a CIE Electronics career course You learn by doing The CIE method of instruction is the refinement of over 40 years of Electronics independent home study experience It works And you don t need any prior electronics experience CIE career course can take you from ground zero right up to training in Lasers Microminiaturization Radar Analog Computers and various applications in Communications In some CIE courses you ll perform hands on experiments and tests with your own CIE Experimental Electronics Laboratory And if TV technology and dig ital Electronics are your main interest you can select from several courses that involve working with and 34 troubleshooting a TV And the TV is yours to keep too This combi nation of head and hands learning locks in your understanding of the crucial principles you ll use on the job in your new career But don t kid yourself Electronics is not an easy science and CIE courses are not snaps Subject matter is technical thorough and challenging It has to be We re training you for a career So the pre sentation of ideas is logical written in easy to understand language you progress step by step at your own pace CIE Education by mail There is no need to go back to the classroom with CIE Because you learn at home or wherever else is convenient You keep your present job
319. uing surveys nearly 4 out of 5 CIE graduates who take the exams get their FCC Licenses No wonder the people who know us best think of us as the FCC License school 1978 Edition CIE independent study courses combine the necessary FCC License preparation with a thorough education in electronics technology In fact one course FCC License and Communications includes that in depth instruction plus intensive training in the specific career skills needed to maintain and repair two way FM radio equipment In addition CIE offers five other career courses which include FCC License preparation Some even provide valuable hands on training with profes sional equipment such as a solid state oscilloscope a Zenith color TV and a color bar generator Learning New Skills Is No Picnic But don t kid yourself You really have to want success if you re going to build your skills properly CIE independent training is no snap even with our Auto Programmed Lessons It takes work and it takes time But when you make it the rewards can be worth it all So if communications troubleshooting looks like the career field you want and want it enough to roll up your sleeves and work for it let us know Send for CIE s FREE School Catalog Mail the card or coupon or write and mention the name and date of this magazine We ll send you a copy or GIE sEREE school catalog plus a V complete package of independent home study informat
320. ulator inputs to the accumulator from the I O device and Slow executes program at about 5 Hz for debugging Front panel MPU inter face via two 34 conductor ribbon cables connected to new front pane interface board Heavy duty pow er supply has 8 V at 18 A 18 V 2 A 18 V 2 A Kil assembled ute etant 750 995 Peripherals and Options The Altair bus is supported by a wide variety of plug in module boards from MITS and over 30 other manufacturers ALTAIR 680b Second generation Altair 680 New version features a 256 byte PROM monitor so that paper tape can be loaded immediately and an Asynchronous Com munication Interface Adapter ACIA that allows the machine to transmit and receive a character at a time rather than one bit The MPU is a Motorola M6800 an 8 bit parallel processor with 16 bit ad dress bus can address 65k bytes of memory has 72 basic instructions Measures 11 in wide 11 in deep 5 in high Comes with power supply front panel control board MPU board with 1k RAM provi sions for 768 bytes of additional PROM or ROM and built in 1 0 that can be configured for RS 232 or TTY A five level baudot interface option is avail able as is a turnkey model without the front panel switches or lights Three additional circuit boards can be plugged inside the case Kit assembled M MM E EE I E 395 495 Altair 680bT Turnkey model with no front panel con trols except halt run and reset Kit wired
321. umber of bits used per word in the memory s organization In our ex ample the ROM would have eight Output pins The address lines for a ROM are usually denoted by the legends A A A etc while the output lines would 1978 Edition be denoted by B B B etc For a five address line input and eight line output ROM the address pins would be labelled A A A A and A and the output pins would be labeled B B B By B B B and B Illustrated in Fig is a basic 256 bit 32 word by eight bit bipolar ROM The address lines are fed to logic gates that decode the 32 possible combinations of 1 s and O s that ap pear on the five address lines These 32 word lines are denoted by the legends wi through wl For the par ticular ROM shown there are eight output transistors whose collectors are labelled B through B The mem ory cells are denoted by the legends T and T There are 256 of these basic memory cells for a 256 bit ROM The output lines from the ROM would be either high logic 1 or low logic 0 depending on whether or not a conduction path exists between the memory cell and the output transistor in each line As an example if aO is to be stored at B in word 32 the T re sistance link fuse symbol must be present If on the other hand a 1 is to be stored at B of word 32 the fuse must be electrically removed blown from the circuit Most ROM s have a pin labelled CE for chip enable
322. user created characters 750 bytes user available RAM Requires 5 V 1 7 5 3 A according to PROM population Wired sss 325 S 100 Bus Motherboard Expansion board for 2650 computer accepts Altair bus memory or I O boards PERENNE 110 Software Editor assembler and BASIC on cassette AG race sarc ML A ee 20 CGRS MICROTECH 4 PUTER 6000 6502 MPU computer consisting of Altair bus MPU board with power up restart front panel Six slot motherboard and power supply al available sepa rately Cabinet available Level II System MPU with 2k RAM 4k PROM 2708 front panel with hexadecimal displays 12 A power 1978 Edition COMPUTERS supply Kit wired erreren 345 425 Level System Same except 256 byte RAM no ROM front panel with binary displays Kit wired huc M aR te ge 265 315 Front Panel Address data reset memory protect and single step switches data and address displays For m Puter 6000 but also plug compatible with Motorola EXORcisor boards Motherboard available for Al tair bus module boards and peripherals Requires 5V 1A Level II Hex display Kit wired 120 180 Level I Binary display Kit wired 90 100 CHILD ODYSSEY MiCOE MACHINE 1802 MPU computer built on two Vectorboards for flexibility in prototyping or education Includes 5 V i 41 x f a 3 aug ie Dum 1i a mS m era E Se 2 use ui fox p x j r T
323. ver again for different programs The unwanted information is simply erased by directing UV light through the IC s quartz window and repro gramming as desired Another type of erasable PROM ELECTRONIC EXPERIMENTER S HANDBOOK PREPARING A PROGRAMMING AND ADDRESSING TRUTH TABLE FOR PROM S Because the PROM is a logic ele ment programming and addressing it must conform to the rules of logic To do this a truth table must be drawn up for the programming procedure This same truth table is also used for ad dressing the ROM after programming has taken place So that stored informa tion can be retrieved There are two approaches you can use when working up your truth table The first is an arbitrary table used mainly for demonstration purposes Since you would key in the address codes by manually setting switches you Can use any address system that suits your fancy The truth table ac companying the diagram in Fig Ais an example of the arbitrary approach For more practical applications ad dress code selection would be under the control of the digital system in which the PROM is to be used In this case the programming truth table for both input and output codes must con form to those required by the system A typical example is a BCD to 7 segment decoder Let us assume a 7490 decade counter s encoded outputis to be used to drive a seven segment LED display Al decoding can be accomplished with a PROM The PROM will t
324. w standards in performance and value In a compact portable case it gives you continuous readings from 20Hz to a guaranteed 100MHz with 8 digit accuracy Fast readings with 1 6 sec update and 1 sec sampling rate Precise readings derived from a crystal controlled time base with 3ppm accuracy High sensitivity readings from signals as low as 30 mV with diode overload protection up to 200V peaks Input signals over 100MHz automatically flash the most significant digit And to indicate low battery condition and extend remaining battery life the entire display flashes at 1 Hz Price 134 95 SPECIFICATIONS Range 20 Hz to 100 MHz guaranteed Gatetime 1 sec Resolution 1 Hz Accuracy 1 count time base error Input Impedance 1 MO 56pF Coupling AC Sine Wave Sensitivity 30 MVRMS 50 MHz Internal Time Base Frequency 3 579545 MHz x tal osc Setability 3 ppm 25 C Temp Stability Better than O 2 ppm C 0 50 C Max Aging 10 ppm year Display Eight 6 LED digits Lead zero blanking decimal point appears between 6th and 7th digit when input exceeds 1 MHz Overflow with signals over 99 999 999 Hz most significant left hand digit flashes allowing readings in excess of 100 MHz Display update 1 6 second plus 1 sec gate time Low Battery Indicator When power supply falls below 6 6 VDC all digits flash 1 Hz Power 6 AA cells internal External 110 or 220 VAC Eliminator charger Auto cigarette lighter adapter 7 2 10VDC ex
325. with 20 slot motherboard shielded against noise and crosstalk 26 A con stant voltage power supply Integrated MPU front panel takes one slot with octal keypad and display reset switch halt run reset examine and deposit for all registers memory locations and I O devices single step and slow step modes display of any de sired data including time under program control Power on reset Case has sliding access panels black vinyl and smoked plexiglass trim Kit 699 Deluxe Hardware Kit No 1 Carrying handle storage for detachable line cord hinged cabinet top tilt up stand for desktop use four additional edge connec je MORTE 100 Deluxe Hardware Kit No 2 Same but with 18 edge connectors to fully populate board 150 Edge Connectors Set of 18 sess usus 70 POLYMORPHIC POL Y 88 8080 MPU in cabinet with five siots 7 A power sup ply up to four independently powered chassis may be plugged together memory may be left on while boards in other cabinets are shut off for debugging MPU board also includes on board real time clock eight level vectored interrupts 512 bytes of RAM up to 3k PROM 2708 type including 1k monitor optional serial 1 O port Mini card Cassette and Printer interfaces fit om MPU card Resets to ad dress zero On power up System 16 Assembied with MPU board video cir ELECTRONIC EXPERIMENTER S HANDBOOK cuit card cassette interface 16k RAM cabinet power Su
326. with printer Prints lines of 20 40 or 80 characters within a 4 in margin 160 char sec 120 lines min Plotting speed two lines sec eight dots vertical per line Graphics resolution 80 dots in with internal timing better than 128 dots in with external timing horizontal vertical resolution 65 dots in Produces either a distinct outline or shad ed graphics as required Wired 785 MOTOROLA M68FD3712 EXORDISK Dual floppy disk mass storage system for EXORcis er and compatible computers Up to 256 k bytes per diskette IBM 3740 compatible 3000 M68R680 EXORTAPE High speed paper tape reader 250 char sec may be daisy chained with EXORdisk 895 M68IFC INTERFACE For EXORdisk or EXORtape 300 M amp R PENNYWHISTLE 103 MODEM May be used as acoustic coupler with telephone handset or wired directly into the telephone via a di rect access adapter Operates in both half duplex unidirectional or full duplex bidirectional modes Records data to and from audio tape communi cates directly with another modem and terminal can record data from a remote source over the phone line and enter the data into the memory of a COIniDUIBt Kita a a ecc ets 130 NATIONAL MULTIPLEX 3M3 DIGITAL DATA RECORDER Uses 3M Data Cartridge Model DC 300 records nearly two megabytes per cartridge on four tracks phase encoded at 9600 baud H
327. y San Antonio TX 78216 STM SYSTEMS INC P O Box 258 Mont Vernon NH 03057 SYLVAN HILLS LABORATORY INC 1 Sylvanway Box 239 Stratford MO 65757 SYNETIC DESIGNS 1452 Prospect Dr Pomona CA 91766 TARBELL ELECTRONICS 20620 South Leapwood Ave Suite P Carson CA 90746 TECHNICAL DESIGN LABS TDL Research Park Building H 1101 State Rd Princeton NJ 08540 TECHNICO INC 9130 Red Branch Rd Columbia MD 21045 TED Box 4122 Madison WI 53711 TEXAS INSTRUMENTS Box 1433 M S 653 Attn TM990 Houston TX 77001 U ROBOTICS INC P O Box 5502 Chicago IL 60680 VAMP INC Box 29315 Los Angeles CA 90029 VECTOR ELECTRONIC CO 12460 Gladstone Ave Sylmar CA 91342 VECTOR GRAPHIC INC 717 Lakefield Rd Westiake Village CA 91361 VIDEO TERMINAL TECHNOLOGY P O Box 60845 Sunnyvale CA 94088 WESTERN DATA SYSTEMS 3650 Charles St Santa Clara CA 95050 WINTEK CORP 902 N 9th St Lafayette IN 47904 WYLE COMPUTER PRODUCTS 3200 Magruder Boulevard Hampton CA 23666 XYBEK P O Box 1631 Cupertino CA 95014 ZILOQ INC 10460 Bubb Rd Cupertino CA 95014 XL ELECTRONIC EXPERIMENTERS HANDBOOK 1978 ADVERTISERS INDEX READER SERVICE NO ADVERTISER PAGE NO 1 AP Products 26 27 2 Avanti Research amp Development Inc 94 3 Byte 118 Cleveland Institute of Electronics Inc 34 35 36 37 4 Continental Specialties Corporation 12 13 6 Datak Corporation 113 7 Digital Group The
328. y board 559 LOGOS 32 32k static memory Kit 1195 8100 UPB Prototyping board s es 40 100 EXT Extender board 40 S100 MB Eight slot expandable motherboard with BDMIOCIONKSE oue ER 90 LOGOS PSIO Parallel serial 1 O board plug com patible with Processor Tech 3P S 145 EXORCISER COMPATIBLE Pin and outline Compatible with Motorola EXOR ciser Micromodules and MEK6800D1 and D2 eval uation kits 9601 16 slot motherboard Wired 175 9602 Card caga Tee eee 75 9610 Utility prototyping board 36 9615 4k EPROM module Kit wired 275 350 9620 16 port parallel 1 0 ssssssse 375 9626 8k RAM Kit wired 275 350 9650 Eight port duplex serial O 395 Al CYBERNETIC SYSTEMS Model 1000 SPEECH SYNTHESIZER Forms words and sentences of standard American English from phonemes requested by ASCII char acters Speech rate and vocal pitch adjustable Re quires less than 50 bytes of assembly or five lines of BASIC for programming data rate typically 25 bytes sec Requires less than 2 3 W maximum Outputs to any amplifier or recorder 325 BYTE PROM BOOT 8k PROM card auto restart from any location in memory uses 2704 2708 PROMS Kit 120 4k PROM Uses 1702A PROMs conserves power by supplying only the
329. yboard Dual Floppy If you are seriously considering the purchase of a microcomputer system for personal or business use or just beginning to feel the first twinges of interest in a fascinating hobby the Digital Group is a company you should get acquainted with For many months now we ve been feverishly and rather quietly at work on our unique high quality product a microcomputer system designed from the inside out to be the most comprehen sive easy to use and adaptable system you ll find anywhere And our reputation has been getting around fast In fact you may have already heard a little something about us from a friend We ve found our own best salesmen are our many satisfied customers There s a good reason Simply the Digital Group has a lot to offer state of the art designs a totally complete systems philosophy unexcelled quality reasonable software affordable prices and the promise that our products will not become rapidly obsolete even in this fast moving high technology field The Advantages Here are a few specific advantages of our product line We offer interchangeable CPUs from different manufacturers including the new super chip the Z 80 from Zilog which are interchangeable at the CPU card level That way your system won t become instantly obsolete with each new design breakthrough The major portion of your investment in mem ory and I O is protected Digital Group systems are complete
330. yment of the music Thus it is desirable on play back to expand the volume to replace the missing peaks On the other hand RS TAPE EXPAND I5K MON IN J A C TARE OFF OUT COMPRESS J3 INPUT IOOK R9 10K J4 TAPE OUT J5 OUTPUT R8 100K PHOTOCELL ges LEAD OI GREEN DOT TO OTHER CHANNEL Fig 1 Sample input to compander is same as input to the speaker itis sometimes necessary to eliminate loud levet changes when using music as a background To provide either expansion or compression of the sound the simple compander described here can be PARTS LIST C 1 220 uF 50 volt electrolytic capac itor C2 1000 yF 15 volt electrolytic capac itor D1 to D5 IN4001 diode or similar J1 toJ5 Phono jack LEDI MVSO light emitting diode or similar Oll Optical isolator Clairex CLM6000 or similar R 1 S00 ohm linear taper potentiometer R2 27 ohm 5 Ya watt resistor R3 220 ohm 5 V4 watt resistor R4 33 ohm 5 V4 watt resistor R5 15 000 ohm 5 V watt resistor R6 100 000 ohm linear taper poten tiometer R7 R8 100 000 ohm 5 resistor R9 10 000 ohm 5 Y4 watt resistor R10 R11 5000 ohm linear taper potenti ometer R12 560 ohm 5 V watt resistor S Spdt center off switch S2 Spdt switch T 1 6 3 volt filament transformer Misc Perforated board mounting clips suitable chassis lettering line cord knobs moutning
331. yon Boulevard North Hollywood CA 91605 PAIA ELECTRONICS P O Box 14359 Oklahoma City OK 73114 PARASITIC ENGINEERING P O Box 6314 Albany CA 94706 PERCOM DATA CO INC 4021 Windsor Garland TX 75042 PERIPHERAL VISION P O Box 6267 Denver CO 80206 PERSCI 4087 Glencoe Ave Marina Del Rey CA 90291 PICKLES amp TROUT P O Box 2276 Goleta CA 93018 POLYMORPHIC SYSTEMS 460 Ward Orive Santa Barbara CA 93111 PROCESSOR TECHNOLOGY 6200 Hollis St Emeryville CA 94608 Continued on page 120 119 ALTAIR COMPUTER CENTERS TUCSON AZ 85711 4941 East 29th St 602 748 7 363 BERKELEY CA 94740 1044 University Ave 415 B45 5300 SANTA MONICA CA 90401 820 Broadway 213 451 0713 DENVER CO 80211 2839 W 44th Ave 303 458 5444 ATLANTA GA 30305 3330 Pledmont Road 404 231 1691 PARK RIDGE IL 60068 517 Talcott Road 312 B23 2388 ANN ARBOR MI 48104 310 East Washington Street 313 995 7616 MADISON HEIGHTS MI 48071 505 507 West 11 Mile St 313 545 2225 EAGAN MN 55122 3928 Beau D Rue Drive 612 452 2567 ST LOUIS MO 63130 8123 25 Page Blvd 314 427 6116 DAYTON OH 45414 5252 North Dixie Drive 513 274 1149 TULSA OK 74135 110 The Annex 5345 East Forty First St 918 664 4564 BEAVERTON OR 97005 8105 SW Nimbus Ave 503 644 2314 LINCOLN NB 68503 611 N 27th St Sulte 9 402 474 2800 CHARLOTTE N C 28205 1808 E Independence Blvd 704 334 0242 ALBU
332. z Quite possi bly the top frequency limit will go even higher than that The power considerations for the ZN414 are on a par with its technical specifica tions The chip draws a mere 0 5 mA from power sources ranging between 1 2 and 1 6 volts Ferranti recommends that the iC be powered from a 1 3 volt source With this low voltage source the ZN414 can drive headphones with impedances rang ing from 400 to 600 ohms without the need GROUND for audio amplification To drive a speaker the IC s output can be easily capacitively coupled to the input of an amplifier to pro vide sufficient driving power While the agc action of the ZN414 is di rectly dependent upon the load impedance hence the need for relatively high imped ance phones a capacitor can be used to isolate the two With the capacitor between the IC and load strong agc action will be observed If you would like to experiment with the IC you can start with the projects de scribed here By special arrangement the ZN414 IC s are available to POPULAR ELECTRONICS readers for 5 each plus 50c postage from Ferranti Electric inc East Bethpage Rd Plainview NY 11803 ELECTRONIC EXPERIMENTER S HANDBOOK AN FAA WEATHER RECEIVER C o Le Tamme a Ke o o R A IK IM RI3 C15 20pF Q MPFI2I 1978 Edition BY MICHAEL S ROBBINS d a So E ao e8on N 2N5172 ORE than 50 Federal Aviation Ad min
333. ze foil pattern top and component placement Note that most resistors are mounted ou end to conserve space The MOS array has 1024 separate photosensitive elements fabricated on a single chip and mounted in a con ventional 16 pin DIP case with a trans parent cover Although similar sens ing devices have cost up to several hundred dollars in the past new tech niques and volume production have made it possible to reduce prices With just 1024 elements in a 32 by 32 array Cyclops can t be expected to match the resolution of a vidicon camera but it is quite useful for many applications The circuit described here is for using Cyclops with a con ventional oscilloscope but it could be altered for a display on a TV tube Among other things a sync generator would be needed A little imagination will enable the experimenter to come up with a number of novel uses for Cyclops For example if a fiber optic light pipe is used with the sensor it could pick up conventional printed material for transmission or to excite a type of tactile device for use by the blind Consider also the possibility of using Cyclops tn conjunction with the 1978 Edition Altair 8800 Minicomputer POPULAR ELECTRONICS January 1975 The combination could be used to build a security system that would operate on the basis of a person s appearance This approach also opens up a brand new and exciting area for the ad vanced experimenter a digital com

1978 - American Radio History

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