Home

compass - American Radio History

1. Covers every major topic in hackerdom On 3 HD PC Disks 39 EES POWERHOUSE ta SRO eh ty NE Sape ty Pr ae Check our catalog for a full line of X 10 Home Security and Home Automation products The Weller WLC100 solder station Is ideal for the professional serious hob byist or kit builder who demands higher performance than usual of a standard iron but without the high cost of an industrial unit Power is adjust able from 5 to 40 watts Includes 40 watt pencil iron UL approved Net weight 1 3 4 Ibs PO 372 120 The Sound Bridge is a mini FM wireless transmitter that can be used to broadcast stereo Sound from any au dio source like poriabie CD players TVs electronic games CD ROM even computer soundcards to your home Stereo receiver Adjustable from 89 to 95 5 MHz PO 249 220 ceecccesccercenenereernsenanenerensneneuneneeens These are the best Sounding little speakers you can find at anywhere near this price Perfect for rear channel use in a home theatre system or for Outdoor use Features 4 polypropylene woofer 2 polycone midrange 3 4 dome tweeter housed In a weatherized polystyrene err closure Frequency response 90 20 000 Hz Impedy ance 4 ohms Power handling 30 watts RMS 60 waits max Mounting brackets included 7 1 4 Hx 4 5 8 W x 4 3 8 D Net weight 6 Ibs Compare PO 319 020 Biack To Special PO 319 025 White
2. HOLS yy cnc Headphones Tuners Wit UG Cleaning kits Triplers emerson maanarox SOE Telephones Idler Tires Connectors Flybacks CATV MATV Lanterns Terminal Pinch Rollers Switches Clips amp Ties Speakers Multimeters Boombox Chemicals Begins E Resistors Antennas Xeelite Weller a Batteries Microphones CED Pedet J Fuses Capacitors z ga Tools And many Idlers many more Belts Order Ne 50 820 yl e ao gt MAGNAVOX Smart Very Smart N bed 9 8 UNIVERSAL AUDIO VIDEO REMOTE Controls basic functions of TV VCR i cable box and CD or laser player H Ergonomic design Main buttons are in line with natural thumb motion Two minute memory allows time to replace batteries without reprogramming Programming reminder sticker inside battery compartment Sleep time for 50 30 or 15 minutes according to your TV Set key recessed to prevent accidental deprogramming Requires four AAA Batteries not included Order N 82 1055 TEMPERATURE CONTROLLED SOLDERING STATION e Voltage Input AC 110V or 220V 50 H2 60 Hz Power Consumption 35 W e Operating Voltage AC 24V Warm Up Time 40 sec Ceramic Heater Element Temperature Indicator C Digital LEO Display Heat Sensor At Element Tip Controlled range from 150 To 420 C Fused Circuit e Low Power High Effection Compare with the majority it requires only 1 2 of electricity
3. E Started In Practical Electronics 5 95 If you are looking into launching an excit ing hobby activity this text provides basic essentials for the builder and 30 easy to build fun projects with which every experimenter should toy Printed circuit designs are included to give your project the profes sional touch SORRY No orders accepted outside of USA amp Canada No of Books Ordered Total price Of BOOKS zd dcia a a Shipping see chart ooo ccc S15 0 6 a a ae Sales Tax NYS OMly ooo ococccoccccecccecceee ce a Amount Enclosed ee All payments must be in U S funds THE HALL EFFECT ELECTRONIC COMPASS F It s easy to stay on the AA gt right course with this p easy to assemble i electromagnetic direction locator DAVID WILLIAMS q Ss lt B D j Xy er stace it If you do much mraveling outside of your home state or even your Mborhood for that matter Byentually you are going to get Host Ask someone for directions Pond it s Go north about a quarter mile then head east another half mile til you come to a creek you get the pic ture Somehow people seem to think that travelers either carry or have a built in compass guiding them through life Well it jist ain t so Of Course if you are in your car provided that it is equipped with a GPS Global Pos
4. 7 Grantham College of Engineering 4 Greenleaf Electronics Inc 88 Home Automation Systems 103 176 Howard W Sams amp Company 1 Information Unlimited 95 13 Interactive Image Technologies CV2 Intronics Ines cece 102 Kableworks o oo _ 92 KDE Electronics 0 86 ume any responsibility for errors that may appear Free Information Number Page KSL Microdevices 102 150 MCM Electronics 85 Mega Electronics WE 147 Mendelson s a 92 174 Mental Automation 3 171 MicroCode Engineering SE Ne CV4 Millennium Enterprises 109 Mo Tech Distributors 106 Modern Electronics 100 Mondo tronics a 92 149 Mouser siisi 100 National Control Devices 98 NRI Schools 19 Orion Electronics 102 156 Parallax CV3 146 Parts Express 2000000 83 175 Pioneer Hill Software 13 45 Prairie Digital Inc 94 46 Prini paahi cab ucts 80 47 PH cratic ee 100 14 Radio Shack E Silicon Valley Surplus 109 Skyvision Inc 8 Smithy Company 107 Starlet Systems 76 Street Smart Security wn 101 Tab BOOKS 7i Tech Services amp Solutions 108 144 e e E N aks 103 136 UCANDO Videos 108 US Cyber
5. Ultra miniature video cameras hidden in smoke and Table Clock alarm or alarm clock your choice Wide field of view Video Cameras and super 1 tux low light sensitivity Undetectable TC 70 High quality B W with 420 lines of SC 600 as resolution for ultra sharp images eTEN neo andai 9189 95 ea ean video and audio Best price on surveillance cameras anywhere net leat San baled he anmannan Smoke Alarm Telephone Transmitter Kit hidden in dual modular adaptor Transmits both sides of conversation to any FM radio up to 1 4 mile Snapkit technology Uses phone line for r and antenna Goes completely unnoticed MA 100 2 5 9 5 tia a mS 4 High quality cassette deck Plugs S o p LA drectly into telephone jack Records up to Z 12 hours of conversations on a single cassette h Recording starts and stops automatically when 12 Hou a Oo sued Visa MC 800 594 1047 Ree mi D99 95 ree shipping Check MO Question tine 972 2557490 Seymor Radix Inc Box 166055 E Irving TX 75016 Now you can visit us on the intemet at http Awww why net home sr Bop erat tay eh cb et Sr PRL a tats these United States and a E UCANDO Videos MasterCard P O Box 928 Popular Electronics August 1997 ah g Videos Learn electronics quickly and easily with UCANDO s computer animated training videos Students can learn at thei
6. 7 f It s exciting It s gigantic The tech nology of tomorrow is here today You ve been reading and hearing about the amazing Information Superhighway It s so new that few technicians are equipped to service Be your own boss it s quick and easy to become an expert at home in your spare time Earn really BIG money adjusting installing and repairing Satellite dish systems TVs Amplifiers CD players AM FM tuners Home entertainment centers Every home every busi ness every office in your area des perately needs your expertise Your timing just couldnt be better Never before and probably never again will you have a ground floor opportunity like this to getinto Belsaw s official diploma attesting to Dept 35391 a booming business of your own your expertise make really big money starting right Nene away b own bo enjo way be your ow ss and enjoy mare financial freedom and security The fact you re reading this message shows you re smart enough to realize this Satellite dish TV Electronics is easy this fast emerging field Foley Belsaw gives you Satellite dish technology including new mini dish along with the electronic expertise you need to make big money servicing TVs and other electronic equipment to learn in your spare time at home This modern practical hands on course combines simple step by step lessons with easy to follow video cassette guidance No special expe
7. C2 13V SHIELDED CASE 2 CS eee i C4 D T4 04 ET J2 aay OY Jal l l R1 i l 10 MEG Q1 R6 i i MPF102 22Q Q2 l 4 7pF MPS3866 I I P5 100Q MAX l R4 4 GAIN 1K CONTROL MN C3 l l i i SEE TEXT a j Ra PL1 12 14 VAC Fig 1 In the 100 kHz 30 MHz Active Antenna incoming signals are picked up by an antenna wire and coupled through C1 to Q1 an MFP102 FET configured as a source follower where the signal is amplified and applied to the base of Q2 an MPS3866 UHF transistor The bandwidth and signal handling capability of the circuit are determined by transformer TI a home brewed trifilar wound toroidal unit Hz power line hum A neon lamp NE1 is used to protect the gate of Q1 from excessive static charge That s because the PVC enclosure in which the antenna is housed tends to develop high static charge levels when handled inducing a charge on the antenna wire That charge might in turn cause C1 to break over and dam age the gate of Q1 Transistor Q1 is biased at 2 5 volts by R1 R3 The sig nal that s fed to Q1 is amplified and applied to the base of Q2 an MPS3866 UHF transistor which can deliver 100 milliwatts output power Transistor Q2 operates at 30 to 40 mA allowing it to handle large sig nals with good linearity Potentiometer R5 the gain con trol connected in the emitter cir cuit of Q2 provides a variable resis tance to boost or
8. Epstein said Therefore when we pump the glass with laser light at the right frequency it is unable to pro duce heat That makes it ideal for this application The cooling power pro duced was only a few percent of the absorbed laser power too ineffi cient for cooling houses or refrigerat ing food yet just about perfect for cooling high tech electronic devices to cryogenic temperatures The experiments funded by the Department of Energy are a giant step toward the goal of initially cre ating what the researchers call the Los Alamos Solid State Optical Refrigerator or LASSOR which would have the ability to cool instruments and devices to at least Phone 508 371 0512 VISA MC Fax 508 371 7129 the temperature of liquid nitrogen 77 degrees above absolute zero Epstein and his colleagues believe that future systems could be at least twice as efficient and be usable at much lower tempera tures A computer model of the sys tem predicts that similar efficiencies should be achievable down to a temperature of 60 K In the Los Alamos design LASSOR light is generated by compact high powered diode lasers in a device with no moving parts and weighing only a few pounds A practical first generation low mass vibration free cryo cooler would be functional in the temperature range useful for high T superconductors infrared detectors and other cooled elec tronic devices Such features would be well sui
9. 00 10 for 28 00 each 100 for 250 00 intermittent use Solenoid body is 0 9 x 0 27 x 0 31 Plunger extends 0 47 Mounted on 3 37 long bracket 4 long leads CAT SOL 45 2 for 12 0 gt 410 UF 300 VOLT PHOTOFLASH CAP Rubycon 1A2304A 0 7 dia X 1 7 long Right angle PC or solder leads on 0 25 centers SQ each CAT PPC 410 6 12 6 12 Vdc MOTOR MOTOR D 10 for 18 50 200 for 320 00 Mabuchi RS 375S 16115 1 08 dia x 1 75 long rf 0 9 dia shaft is 0 5 long 4 Solder terminals j s13 Re CAT DCM 80 AUTOMOTIVE POWER CORD 3 foot wire Cigarette lighter plug to 2 1mm co ax plug center positive polarity an 10 for 12 50 3 th 100 for 100 00 12 Vdc CPU FAN Enertron NX586 022 20 7 blade mini 12 vdc fan on a heatsink Assembly is 2 square X 1 22 high Heatsink has a 0 87 square flat area on side opposite fan from which fins radiate One fin extends 0 63 beyond the others Inctudes two mounting clips 50 CAT CF 40 each 1 800 826 5432 ORDER TOLL FREE MAIL ORDERS TO Popular Electronics August 1997 oO FAX 818 781 2653 INFO 818 904 0524 INTERNET http www allcorp com E MAIL allcorp allcorp com ALL ELECTRONICS CORP P O BOX 567 VAN NUYS CA 91408 0567 NO MINIMUM ORDER Ail Orders Can Be Charged to Visa Mastercard American Express or Discover Checks and Money Orders Accepted b
10. Acoustic Research System Requirements 486 CPU or greater 8 MB RAM minimum s Win 95 NT or Win 3 1 Win 32s Mouse and Math coprocessor a 16 bit sound card PHS Sales 360 697 3472 Priced from 299 U S sales only not for export resale Professional Quality Sound Cards Available Call DOWNLOAD FREE 30 DAY TRIAL www telebyte com pioneer Spectra Plus 4 0 Affordable Signal Processing Software Pioneer Hill Software 24460 Mason Rd N W Poulsbo WA 98370 Fax 360 697 7717 e mail pioneer telebyte com CIRCLE 175 ON FREE INFORMATION CARD 91u01 99 3 seindog Z664 Isnbny Q New Products Stand Alone Windows 95 NT DSP Applications The Hypersignal Application Interface or HAppi Wizard quickly generates Stand alone digital signal processing DSP applications for Windows 95 and NT It does this directly from visually designed real time DSP worksheets created in Hyperception s Block Diagram editor Those applications can then be applied internally or shipped to an end customer The product lever ages the many off the shelf DSP ac quisition boards supported by the com pany s Hypersignal RIDE Real time Integrated Development Environment Ele View Contiol Pioject Help of a which reduces overall product develop ment time It also dramatically mini mizes the technical expertise required for the simultaneous development of 32 bit Windows app
11. Golden Eye which measures distances using ultrasonic waves The ProMeasure serves as both a measurement computer and a conver sion calculator and separate control pads are found on the front and back of the device The measurement comput er features an LCD readout and nine turquoise buttons SUM CLR SUM MODE RECALL L W H AREA and VOLUME Along the sides of the unit are two ON buttons used to trigger the measuring system The conversion calculator has its own LCD an array of calculator keys numbers and functions and several touch pad con version buttons for selecting the materi al to be calculated AIR HEAT TILE C TILE F PAINT RUG 4X8 and ROLL In addition there are soft keys labeled RECALL ON CE and MODE Measuring a room couldn t be easier You just place the base of the ProMeasure Plus against one wall hold it parallel to the floor and press and release the sc xsc key Make sure that the unit has a Clear line of sight with no furniture to get in its way When the measurement is complete a matter of seconds you ll hear four beeps The MODE button is used to select one of the three different display modes English standard feet and tenths of feet Imperial feet and inches and metric meters and centimeters On screen indi cators let you know if the measurement displayed is in feet feet and inches or meters For instance if a room is 22 feet t
12. 8 30 PM EST Advertising Sales Offices listed on page 110 Composition by Motes Graphics Cover by Lonwy Design Cover Illustration by Chris Gould ABC AUDITED Since some of the equipment ane cireuil ry described in POPULAR BLECTRONICS may relata to or be covered by US patents POPULAR ELECTRONICS dis claims any liability for the infringement of such patents by the making using or selling of such equipment or clecuitry and suggests that anyone interested in such projects consulta patent attamery Announcing mentaIMAX The First All In One Circuit Design Software Package Only 549 SuperCAD C SUPERCAD EXAMPLE S ASTABLE PIC a z SS AE 3 Ec pm u pN pu rna prs m IE mi oe 4 a aj y Complete Schematic Entry Software mentalMAX includes the easy to use powerful SuperCAD sche matic entry software SuperCAD comes with nearly 1800 parts in cluding most TTL and CMOS logic opamps discrete symbols and others plus you can easily add custom symbols Because of our association with McGraw Hill in procucing the En cyclopedia of Electronic Circuits CD ROM available separately for 99 the SuperCAD schematic editor is fast becoming a stan dard for schematic entry The Encyclopedia includes 1000 SuperCAD schematics in 142 different categories audio radio etc that can be used as a Starting point for designs Mixed Mode SPICE Simulator For simulating purely analog circuits or circuits with so
13. Figure 9 shows a high gain audio amplifier for use with direct conver sion receivers The circuit is built around an LM386 audio amplifier housed in an 8 pin DIP package that is used to drive an 8 ohm speaker or earphones through Cl Continued on page 75 12V ne 2 F ez SPKR1 BQ J AUDIO C1 INPUT 220 a 4 Fig 9 Here we have a high gain audio amplifier for use with direct conversion receivers The circuit built around an LM386 audio amplifier is used to drive an 8 ohm speaker or earphones through C1 s31u01498 3 seindog Z664 IsnGny D Ww Popular Electronics August 1997 THE LASER FRIDGE IT S COOL Who would have ever thought tha heat could be used to generate co Attachment Plate Vacuum Casing i Diode Laser DOUGLAS PAGE G overnment scientists are cooling it with lasers Using a 70 year old theory for the first time researchers have proven that under the right conditions the sear ing radiation in laser beams can actually be used to cool solid mate rial It is the first successful demon stration of an optically cooled solid Los Alamos National Laboratory experiments have shown optical refrigeration to be not only possible but efficient enough that someday the process could provide reliable cooling for cryogenic electronic instruments in space and ultra fast computer circuits on your desk as well as other uses Data from laboratory measure ments combi
14. J C18 C16 Jl 100 680pF l Fig 5 You can use this circuit as a stand alone amplifier or as a preamp for the 7 watt Stereo power amp purpose of the LM78L09 voltage regu lator here is to match the power supply of this preamplifier to the supply of the mini stereo power amplifier should you use this circuit as its preamplifier Exclude IC1 if you use an external 9 to 12 volt supply and connect the DC directly to pin 6 of IC2 and IC3 Jose ignatius A Alea Philippines It looks as if all the parts for this circuit are available at local distributors too For stand alone use you will need a volume control Perhaps placing a stereo potentiometer at the input will do Cebu Fuzz Amplifier John have an electric guitar local ly made but it sounds like the big names As you already know guitar for rock or heavy metal is not complete without fuzz So threw some parts together and the result shown in Fig 6 is a superb circuit that makes my guitar sound very fuzzy The circuit built around an LM386N 1 low power voltage amplifier IC not only produces fuzz but can also amplify the signal from the guitar The guitar signal is fed to jack J1 and coupled to the inverting input of IC1 by way of C1 and R2 The input coupling capacitor should be a ceram ic type The input signal is clipped by back to back diodes D1 and D2 and produces a distorted signal When the signal appears at output pin 5
15. New BASIC Stamp Rev D Kit 79 Get started with Rev D Stamps Includes our original BASIC Stamp rev D manual software and programming cable _ New _ Basic Stamp 1 Starter Kit 99 1 Design your project today us ing the Basic Stamp 1 In cludes a BS1 IC carrier board manual software and pro gramming cable New Basic Stamp 2 Starter Kit 149 Take advantage of all the cool features of the Basic Stamp 2 This Starter Kit includes the BS2 IC carrier board manual software and programming cable For more information on the Starter Kits visit our Website at http www parallaxine com 3805 Atherton Road 102 Rocklin CA 95765 USA Office tech 916 624 8333 Fax 624 8003 FaxBack 624 1869 E mail info parallaxinc com Web address http Avww parallaxinc com 2 Singapore 65 296 3995 Slovak Republic 42 7 580 2574 South Alrica 27 11 493 6242 Sweden 46 70 576 14 54 46 431 41 00 88 Switzerland 49 241 918 900 Talwan 886 2 647 1978 United Kingdom 44 1 977 683 665 United States 800 344 4539 Digi Key 800 831 4242 Jameco 800 538 5000 JDR 800 652 6733 Marlin P Jones 800 467 7736 DC Electronics 415 455 9330 Mondo Tron cs PBASIC BS1 IC and BS2 iC are trademarks and BASIC Stamp amp the Parallax logo are registered trademarks of Parallax Inc Prices do not include shipping and applicable sales tax Features an d prices Subject t
16. chirp Police radar lt ROCKY MOUNTAIN RA de in FR the waiting radar unit an electronic loboto my Best of all unless you are a resident of Minnesota Oklahoma or Washington DiE using the Spirit II is completely within your lega rignts How i scrambles radar Police radar takes five to 10 measurements of a vehicle s speed ir about one second The Spirit Il sends one signal that tells the radar the car is going 15 m p and another signal that the car is going 312 m p h Because police radar can t verify the speed it displays no speed at all To the radar gun your car isn t even on the road Radar and laser scrambiers are de vices that foil speed traps by making vehi cles electronically invisible to police radar Radar scrambless mix a portion of the radar signal with background clutter and reflect it back to the squad car This technique pioneered by Rocky Mountain Radar creates an unreadable signal that confuses the computer inside the radar gun The laser scrambler in the Phazer works in a similar manner It transmits a special infrared beam with information designed to scramble the laser Signal The result Readouts on police radar and laser guns remain biank As far as the police officer is concerned your vehicle is not even on the road es facturer will pay pour speeting ticket Range up to three miles The Spi
17. 5 01 to 10 00 3 00 10 01 to 20 00 4 00 20 01 to 30 00 5 00 30 01 to 40 00 6 00 40 01 to 50 00 7 00 50 01 and above 8 50 Eon PC Specifications 7 25 This book explains PC specifications in detail and the subjects covered include the following Differences between types of PC XT AT 80386 80486 Pentium etc math co processors input devices keyboards mice and digitizers memory including both expand ed EMS and extended RAM RAM disks and disk caches floppy disk drive formats and compatibility hard disk drives and display adapters CGA Hercules super VGA etc BP298 Concise Intro to the Macintosh System and Finder 6 25 Although the Mac s WIMP user interface is designed to be easy to use much of it only becomes clear when it is explained in Simple terms The book explains The System and Finder what they are and what they do how to use the System and Finder to manipulate disks files and folders cOnfigur ing and printing files from the Finder getting the most from the system utility programs and running MultiFinder BP301 ANTENNAS FOR VHF AND UHF 6 00 From installing a TV or FM antenna to setting up a multi antenna array for shortwave listening or ama teur radio this book explains the essential basics of VHF and VHF antenna operation and installation In Gasy
18. 9120939 XX 69 50 Hardcover Counts as 2 0535469 29 95 How to Read Electronic Circuit 1554637 16 95 g pen BLR Understanding Electricity a Electronics ae 0582157 26 95 Trogaiesheoting amp Rasairieg Compact Esc Players 0157625 24 95 1573119 19 95 0857311 44 95 0215286 19 95 soiuooe9 seindag 7664 Isnbny J Popular Electronics August 1997 72 winding of the transformer When S1 is released the transformer s stored energy appears across the winding briefly lighting the neon lamp If one of the transformer s windings has a short most of the stored energy will be dissi pated within the shorted section and very little will appear across the lamp The lamp will remain off or just barely flicker Here s an easy way to demonstrate the effect of a shorted winding in a multi tap transformer Connect a good transformer to the test circuit and briefly operate switch S1 to confirm that the neon lamp glows Tie the leads of any other winding of the trans former together and repeat the test The neon lamp should remain dark S1 PUSHBUTTON N O R1 50K ALLIGATOR CLIP 1 5 TO 6VDC DC POWER SOURCE Fig 7 Don t throw away your old analog DC meters With this circuit you can mea sure the internal resistance of the meter Then use Ohm s law to calculate an exter nal shunt resistor to give you an extended full scal
19. 99 00 New Low Price Same Size Covert Camera 1 1 4 sq Pinhole Lens 169 00 Pro Grade Japanese Quality Audio Module Now Available Calf Check MO COD 5 00 S amp H 5 50 WN 671 1225 E t Dr AEGIS Bellingham Prelit Greenleaf Electronics y 98226 3529 USA 1 800 742 2567 1 604 224 0416 NO ILLINOIS SALES Visit our virtual catalog on the INTERNET at It is not the intent of Greenleaf Electronics to defraud any pay television operator http Jiwww lynx be ca vi rtualspy and we will not assist any company or Individual in doing the same FM TRANSMITTERS AG TOLL FREE ORDER LINE 1 800 336 7389 LiNE 1 602 731 4748 FUN PROJECTS j TECH SUPPORT NUMBER 1 602 829 0755 AND MORE XANDI ELECTRONICS INC ANGE W N YOUR MANUFACTURER OF HIGH QUALITY KITS i CRYSTAL TRANSMITTER KITS bf XBD500 Ultra miniature surface mount construction f P 129 95 E G E Z kit approach makes assembly a snap f ff Professional quality h ae F Ae r rat Assembly is a snap a ey Miniature battery and holder will mount I E le directly to the circuit board E O cere Nc UA XTR300EZ XTL3000EZ XTL1 000EZ Transmit to any scanner type receiver E s eae pti ea 79 95 99 95 69 95 Le F Adjustable sensitivity XTR300 XTL3000 XTL1000 g Audio jack for privacy ear phone TRACKING TRANSMITTER KIT LONG RANGE TRANSMITTER KIT TRANSMITTER KIT Any intercepted signal causes an audio Transmits continuous beep b
20. A NEEE A 45 on Pas To fully appreciate the potential of movie soundtracks a dual voice Coil subwoofer is a must Many film spe cial effects are extremely demanding in the low frequency range and re quire a subwoofer that can duplicate explosions earthquakes even the footsteps of Tyrannosaurus Rex This subwoofer fits the bill by featuring a 10 dual voice coil woofer for true stereo op eration and high pass filters for your main speakers The most unique feature of this subwoofer is the fact that it is designed to be mounted in between the floor joists in new and ex isting home constructions Simply mount the in floor sub to the joists and mount a heat register grill above opening in subwoofer front enclosure The subwoofer is now totally out of view and ready to rumble Includes detailed installation Nanual Specifications 10 dual voice coil treated paper cone woofer with poly foam surround Frequency response 30 100 Hz Nominal impedance 8 ohms per coil Power handling 100 watts RMS channel 140 watts max SPL 89 dB 1W 1m Dimensions 27 D x 14 5 8 W x 9 H Net weight 29 Ibs PO 300 445 cccccccccreerceneescetteresrecersreerssancanarerseesssarenan agers EACH 30 day money back guarantee 20 00 minimum order We accept Mastercard Visa Discover and Company C O D orders 24 hour shipping Shipping charge UPS chart rate 1 90 5 00 minimum charge Hours 8 00 am 8 00 pm ET Monda pm Saturday Mai
21. Like thousands of other American homeowners who save money by making their own home improvements we found ourselves heading to Home Depot to check out primers and paint as well as wood flooring for the office and hallway Then we headed over to the carpet outlet center to search for the perfect rugs for the master bedroom and the nursery Paint chips in hand we strolled through the aisles of rolled up rugs trying to match colors We actually found a Carpet in a soft shade of green that could work in both the master bedroom and the nursery and the price was good We wanted to buy it on the spot to save another trip to that store but we realized that we had no idea how much we would need Three rolls were available 12X28 feet 12X35 feet and 12 X 50 feet The nursery is 11 X 10 feet the master bed room 14 by 15 plus that little section by the door one standard closet and a large walk in Shouldn t they be carpeted too And if the price was so reasonable how much might we save by carpeting the office also instead of installing a hard wood floor in there It was at that point that we realized that we had no idea how much paint we would need either All of our previous painting jobs had involved one small room at a time a gallon generally did the trick We figured we d better go home and pull out the tape measure and the calcula tor before we pulled out any credit cards We d get accurate measurements of
22. Millions degree temp eui luminates low BTC3 Plans 4 Piaces subjects under your J control Programmable audible amp visual stimuli with biofeedback Induces strange amp bizarre halucinations without drugs Caution not FDA approved 149 50 1 MIND2K Kit and Plans jon Motors e Strange and bizarre pyrotechnical effects 1 BTC3K Kit Plans with coil level clouds e Light Shows fi s Window Listener M BTC4 A Pan peo al unit e Optical Projects a sa x z 12 115V fi casos Science Project f BTC30 Assbid Ready to Use Generator Levitate an object T Great science fair project Includes text book on Anti Gravi Monitor your premises avoid break ins 3 Mi Voice aaa f 4 Ultra Sensitive Mike aq Crystal Clear 4 e Tunes 80 130 MHz FMVIK Kiv Plans J Drop In imi T i Telephone Transmitter Easily tunable over FM radio Nove needs NORN KivPlans a 19 95 40S 5 00 49 50 MIND20 Assembled Unit 69 50 1 HEPIK Kit Plans with 500J 4 HEP10 Lab Assembled to your spec s a call or fax for ii amp seats e Powers light and 1 objects without contact 4 e Experiment with electrical and mechanical 99 50 8 149 50 TCLSK Kit Plans A inte Electronic ASA Hynotizer 1 Control their minds Programmable audible and visual stimuli induces hypnotic i 4 trances HYP2K Kit with Book Scope with
23. Milpitas CA 95035 800 998 5227 408 428 6600 http www creativelabs com CIRCLE 64 ON FREE INFORMATION CARD New Hardware Another neat new piece of hardware this month is the TV Box from Proview Technology This 181 channel cable ready tuner connects to any VGA mon itor You can switch between TV and your PC but cannot watch TV in a win dow You don t even need a computer all you need is an antenna or cable TV the TV Box turns an old color 14 inch monitor into a low emission high resolution remote controlled color TV The TV Box even has a built in speak r SO your monitor doesn t need one And for you couch potatoes out there everything is controlled by a 23 key infrared remote The TV Box costs only 119 less than most color TV sets A detailed review of this product Discovery Channel Multimedia 7700 Wisconsin Avenue Bethesda MD 20814 800 678 3343 317 579 0413 http www multimedia discovery com CIRCLE 65 ON FREE INFORMATION CARD Expert Software Inc 800 Douglas Road Executive Tower Coral Gables FL 33134 305 567 9990 Fax 305 443 0786 http www expertsoftware com CIRCLE 66 ON FREE INFORMATION CARD Proview Technology Inc 12272 Monarch Street Garden Grove CA 92841 800 PRO VIEW 714 379 4455 CIRCLE 67 ON FREE INFORMATION CARD Psygnosis 919 East Hillside Bivd Foster City CA 94404 800 438 7794 415 655 8000 http www psygnosis com CIRCLE 68 ON FREE INFORMATION
24. Z664 ysnbny J Popular Electronics August 1997 THE LASER FRIDGE Continued from page 44 explains physicist Richard Epstein of Los Alamos Nonproliferation and International Security Division the leader of the research team Light pours onto the object soaks up some of the vibrational or heat ener gy of the object then carries away the excess energy In work done previously in this field attempts to cool solids with light resulted at best in a reduction in overall heating rates no net cooling has been achieved until now The researchers managed this break through by using a tunable laser and modern fiber optic material in the process suppressing the usual heat ing thereby making optical cooling dramatically apparent Nature wants to produce heat but we ve discovered how to use laser light to excite an object to special quantum states in which it can trap thermal vibrations but can t create them Epstein explained Essentially we tune the laser to out smart the nor mal tendency to produce heat How It s Done To create laser cool ing the researchers focused a beam of infrared light nearly as intense as the light emitted at the surface of the sun at a sliver of ultra pure glass which had been doped with ions of the element ytterbium Ytterbium ions radiate over only a single band of frequencies which are much higher than the possible frequencies at which the glass could radiate
25. dows at either side of the knob then indi cate outside drawn along the outside edge of the ruler and inside angles Tightening the knob keeps the angles pre cise as you draw The ProLevel s visual and audible indi cators cannot be used to measure plumb lines You can use the device s second bubble level and trust your eyes for that purpose If you ve become too dependent upon lights and sounds how ever you can adjust the protractor to a 90 angle line that up with the vertical Surface and then use the ProLevel hori zontally to measure a plumb line Perhaps we ve become jaded being exposed to so many gizmos all the time But when it comes to levels we don t believe any bells and whistles are required Of the features offered by the ProLevel and not found on standard mod els we most appreciated the manual one the protractor 2 ee e a HEY COUCH POTATOES Continued from page 22 is the place where we want to access the Internet But the Philips Magnavox WebTV terminal has convinced us that it s far better than using a bad ISP and a slow modem The terminal s built in modem runs at 33 6 kilobits per second It can t download data and it can t print not yet But the terminal has an expansion connector so like everything else about WebTV expect it to get even better in the future i DVD DEBUTS Continued from page 23 somewhat united functioning front We add that qualifier becaus
26. 15 Mayflower FRA kpdsMe Stine PARA Sales Tax Aliso Viejo CA 92656130 day BACK GUARANTEE Money Back Guarantee women os The clearest picture possible playing back movies GUARANTEED to eliminate copy protection No Rolls Jitters Flickers Fading Works on all TV s VCR s Beta amp Cable Gold Video Connectors amp Cables Included 1 Year Warranty ELECTRONICS 1 800 562 2252 2609 S 156TH CIRCLE OMAHA NE 68130 630 736 9822 will find the the best S Rte nm Vise A MOLIOR Build your own functional Robotic Arm The kit comes complete with all hardware base enclosure structurat alia d 6 Hitec servos MiniSSC servo controller kit Quick Basic software and an llators Digital T gt a Small mobile robot base It is a great foundation for artificial our web site for more information and other robot kits 3 Axis Version 155 00 Mobile Version 250 00 Many more robots ask for our free catalog Technical Service amp Solutions 104 Partridge Road Pekin IL 61554 1403 USA Axis Robotic Arm Kit illustrated assembly manual This robotic arm can be controlled from any micro with a serial port It makes an excellent addition to intelligence experiments and teaching motion control Check out http www modernelectronics com BROADCAST FARTHER The model 220 Is a 80 110MHz RF amplifier that co
27. 5 percent and men 35 percent included 1242 eyes with acuity lower than 10 percent for far vision The patients suffered a wide variety of eye defects including ametropia retina and optic nerve diseases and even those that could not be exactly pin pointed Nearly all fittings were suc cessful with the few failures in peo ple who did not complete the train ing needed to use the regained vision and subsequent increased mobility Training that takes three months includes learning how to recognize and focus on objects The Soltis technology has recently been approved by the French govern ment and is now being used in ten French hospitals often on even younger patients It is to be hoped that the technology will soread to other countries including the United States Cochlear Implants for the Deaf Sensorineural hearing losses or nerve deafness result from dam aged or depleted hair cells in the inner ear Without healthy hair cells there is no way to convert sound into electrical current to stimulate the auditory nerve Sensorineural hearing loss can come from loud noises head injuries medications infections or can be hereditary For individuals with a profound hearing loss even the most power ful hearing aids may provide little to no benefit Unlike hearing aids that collect sounds entering the ear and amplifying them the cochlear implant can help people with sen sorineural hearing losses by byp
28. 7mm Wide Angle Lens Built In Backlight Compensation items May Be Purchased by Credit Card Certified Check Money Order or C O D their future when you buy products made from recycled materials For a free brochure write Buy Recycled Environmenta Defense Fund 257 Park Avenue South New York NY 10010 or call 1 800 CALL EDF sepa REDDF ROBOTIC MACHININ ROUTE MILL DRILL CARVE ENGRAVE PAINT IN WOOD PLASTIC VINYL PC BOARD amp LIGHT METALS 4 amp 5 MOTOR GANTRY MILL CONFIGURATIONS PC COMPUTER CONTROLLED CNC ONC IMPORT EXPORT FILES TO OTHER CADS AUTO BACKLASH COMPENSATION PRE MACHINED HEAVY CASTINGS SIMULTANEOUS 4 AXIS MOTION FREE 3D CAD CAM SOFTWARE AVAILABLE IN KITS OR ASSEMBLED EXPEDITE SERVICE ALSO AVAILABLE OPTIONAL ALUMINUM WAY COVERS 0005 RESOLUTION AMERICAN MADE 3 amp 4 AXIS UNITS FROM 12 X 12 TO 66 X 66 MACH AREA soiu0sjoa q seindog Z664 Isnbny eet a ata ae 4 kk O START A CAREER IN ELECTRONICS Accredited home study Re P pair install and service au t eb A dio equipment microwave ior nl ovens alarm systems small ie et appliances and more For free 1 7 J l career literature send or call Vit i CALL 800 223 4542 Name 7 Address E ee City State Zip Age Pho ie i The School of Electronics Dept ELJ341 ace 6065 Roswell Road Atlanta GA all
29. Beige into a h aasa anua Cheese amp CF Boxes ESS 57 E 311 vat ous Class services CN A Non Pub DA CAMA DNR 800 ECR Diverters LD Extenders Centrex muchmore 19 about 8 Billion yr PBX wld 1A RAAEEU Ti TTo Hacking exposes all issues CORDLESS MODS relating to PBX hacking in cluding countermeasures This manua was featured in Forbes Magazine Shocking VOICE MAIL HACKING Exposes how Voice Mail Box j systems are used and specific ways they are hacked k Includes ASPEN MESSAGE s CENTER BIX GENESIS RSVP i CENTAGRAM EZ AUDIX SYDNEY PHON MAIL CINDY SPERRY LINK etc A must for all users hackers and security personnel 3 The ultimate cellular modification uide See our Catalog for our in amous cellphone mod guide very ya detailed comprehensive covers 29 wees f most makes 10 times more info than any competitors manual JI THE Ta LELIE IEA Ur Compilation of 100s of the best arassed Manipulated Forget job eye opping articles written b to ithera pheeakers ASCII text performance This manual outlines what it really takes to make it to the top in today s corporate BS world 15 Att New TOP Secret CATALOG FEATURES 200 SURVIVAL PRODUCTS Wii Rock Your Wordi Mai 3 OR 1 WITH ORDERI ORDER TODAY
30. CIRCLE 26 ON FREE INFORMATION CARD YOUR p Ai Electronics Authority 85 Channel Cable Convertor Includes last channel recall channel memory switched AC outlet and sleep timer Remote requires two AA batteries MCM 290 070 Regular price 59 95 Order 33 2065 ATC Lead Wire Fuses Finally there is a fast easy low cost way to tap an automotive fuse box Expanded fuse tap contacts can short out fuse boxes but not ATC lead wire fuses Order Amps Order Amps 60 3855 5 60 3375 20 60 3860 7 5 60 3380 25 60 3865 10 60 3885 30 60 3870 15 Magnet Mount Cellular Antenna Offer in effect only while supply lasts Sturdy magnet mount antenna holds firmly in place at highway speeds Also works well as a scanner antenna Overall antenna length 13 Includes 12 RG S8U cable with attached molded TNC connector Suggested list 9 95 Limited quantities Order 58 2605 Replacement 3 Floppy Drive 1 44MB Perfect replacement drive with standard IDC and Molex connectors for use in most PCs Mitsum model D359T3 Suggested list 29 95 Order 58 2535 VCR Model SuperCross Allows you to cross reference VCRs with all models that are mechanically the same Great for second sourcing parts service manuals and more Crosses over 2000 VCRs Regular price 29 95 Order 81 2055 Hours M F 7 a m 9 p m Sat 9 a m 6 p m EST Visit MCM s website at www memelectronics
31. Learn to A EITEK SUPERPRO UP 99 EPROM 4G TO IMEG Showed Up Late rogram the LCD ke ad di ital 249 XELTEX SUPERPRO L 199 EPROM 14G TO 1 MEG prog L7 KCyp gitat 165 XELTEK ROMMASTER I 89 EPROM 1G TO 8MEG analog and serial I O for your applications 479 MOD MCT EMUPA 129 EPROM 4G TO 8MEG Never Taken A 250 EPROM 8G TO 8MEG m St i A Lastoovas MICROMASTER SUPERPRO ALLMAX PLUS ROMMASTER General Device Instruments Sales 408 241 7376 Fax 241 6375 BBS 983 1234 Web www generaldevice com E Mail icdevice best com t programmer g that uses the 4printer port of 3 instead of a t programs E E prom Flash amp Dallas Ram 27 C 28 C F 29 C F 25 series from 16K to 8 Megabit with a 32 pin socket Adapters Pin X 16 amp Serial Eprom s PLCC 5 Gang and Eprom Emulator to 32K X 8 Same Name Address amp Phone for isn t it Amazing Fax 913 441 1623 visal Master Charge Whaddya Say To A Guy Whos Had The Same Job For 50 Years Has Never Called Vacation Or A Holiday Never Asked For A Raise Or Griped About His Bonus And Believe It Or Not Has No Plans For Retirement your PC internal card 75X Pic 40 St Add 4 75 COD 4 00 Shipping Remember only you can prevent forest fines WHOLESALE PRICES STARTING AS LOW AS 99 00 CABLE TV DESCRAMBLERS CONVERTE FILTERS VIDEO STABILIZERS
32. TX 75243 Tel 214 343 8525 Fax 214 343 2457 E mail info hyper ception com Web http www hyper ception com BBS 214 343 4108 CIRCLE 80 ON FREE INFORMATION CARD Handheld GPS Communicator For people whose business or recre ational pursuits take them off the beat en path and out of reach of conventional communications the Magellan GSC 100 Global Satellite Communicator allows them to stay in touch wherever they roam The portable receiver trans mitter puts worldwide two way e mail oe es i capability in the palm of the hand The GSC 100 also features an integrated GPS receiver for positioning and navi gation allowing users to navigate and communicate from anywhere on earth Field professionals in disciplines rang ing from seismology to oil exploration outdoorsmen hikers pilots internation al travelers and all kinds of mariners can benefit from the technology The GSC 100 communicates via ORBCOMM the first low Earth orbit satellite communications system Users can send and receive text messages in an e mail format to and from anywhere in the world including another GSC 100 It can be used as a handheld ter minal operating on its rechargeable NiCd battery pack or it can be bracket mounted and operated by a 10 35 volt DC external power source The self contained 8X3 5x1 75 inch 37 ounce unit includes everything needed for Satellite Communications and naviga tion ORBCOMM communications transceiver
33. The word heterodyne implies a process whereby two different frequencies are brought together in a nonlinear mixer circuit to produce several new frequencies Figure 1 shows a block diagram of the typical super heterodyne receiver front end cir cuit The mixer stage receives two input frequencies one is the incoming RF signal f that we want to receive and second there is a signal f from the local oscilla tor Tuning a superhet radio is accomplished by varying the fre quency of fp The mixer in turn out puts several frequencies fy fo the sum of fy and fo the difference of f and fo plus the sums and differ ences of the galaxy of harmonics of f4 and fp Those frequencies are defined by the relationship mf Nf where n and m are integers 1 2 3 A frequency selective filter at the mixer output selects which of all the frequencies is to be used let s label it f3 the intermedi ate frequency IF In most superhet radios the IF fa RF INPUT f4 FREQUENCIES mf nf Fig 1 Shown here is a block diagram of the typical superheterodyne receiver front end The mixer stage receives two input frequencies one is the incoming RF signal f and the other is from the local oscilla tor f Tuning the superhet receiver actu ally varies the frequency of f2 is the difference between fj and fo so the front end is called a down converter In modern communica tions receivers howeve
34. brand names are registered trademarks of their iy 110 84 NONYS SALES reference only Bivd 465 Forest Hills NY 11 yrs gt Cc Q T 7 m i ce N Bs 2 p lt m 9 O e 2 O ive fe Popular Electronics August 1997 110 eaten ADVERTISING INDEX Popular Electronics does not ass in the index below Free Information Number Page 25 Ace Communications 86 Aegis Research Canada 88 Lt a n 102 26 Alfa Electronics 84 28 All Electronics 96 137 Allison Technology 10 Allstar Electronics 109 Amaze Electronics 10 AMC Sales ecco 92 American Innovations 107 Andromeda Research 103 Basic Electrical Supply 80 32 C amp S Sales Ine 104 CD Electronics 0200000000000 94 Circuit Specialists 90 Cleveland Institute of Electronics 37 Command Productions 94 Comtrad Industries 5 9 Consumertronics 000 0 000 00 0 82 48 Dalbani ssis 93 EDE Spy Outlet iaei 108 148 Electronic Rainbow re 87 Electronic Technology Today 32 79 NN OS ppa 10 Foley Belsaw a 99 Forest Electronics 88 Fotronic Corporation 98 General Device Instruments 102 George Brown College
35. effects channel To take full advantage of Dolby Digital a de coder is required Some high end DVD players have built in decoders the rest ae have outputs that allow a stand alone de coder or receiver equipped with a decoder to be connected If your AV system does not yet include a Dolby Digital decoder don t werry DVD works perfectly well with a Dolby Pro Logic setup too DVD players are also backward compatible with audio CDs and video CDs The DVD format boasts the conve nience and durability factors that helped make compact discs so popular DVD video discs provide instant access lo spe cific scenes in a movie and there s never any tedious rewinding required They can be played literally millions of times with out degradation of quality All of that translates to exceptional home theater entertainment But there s a good reason that some people call DVD digital versatile disc instead of digital video disc After all watching videos is only one DVD application By the time you read this DVD ROM drives for personal computers also should be available DVD ROM discs will hold up to 20 times more than CD ROMs A single sided single layer DVD has 3400 times the capacity of a floppy disk That s good news for multimedia users since it will allow for enhanced game play with improved graphics faster action and extended 3D animation DVD ROM drives could also give com puter manufacturers a new way lo get PCs
36. gt 20MS e real time sampling z GHz equivment time sampling at 0 1uB div gt Prints via AS 232 port to any HP GL plotter Quality Scopes by Elenco Fer pui i E i gt 20MHz ANALOG WITH DIGITAL STORAGE MHz analog bandwidth 20 Model 2522A 20mS s sampling rate 2K memory per channe 300MHz equivalent tima sampling S gt SOOM ec es mee 869 95 100MHz THREE TRACE ImVititvision sensitivity Modei 2190A sweeps to Snavdivision Dual time base Signa detay line 8KV accelerating voltage 1379 95 ieee A NN paranana a me ey eS ae 60MHz 40MHz 25 30MHz ps s03 1350 s 1345 569 ps 303 1095 Analog Digital Storage Analog with Delayed Sweep Analog Digital Storage Analog 25MHz Analog S 1360 749 Delayed Sweep Analog with Delayed Sweep S 1325 325 e 25MHz Analog 60MHz DUAL TRACE Im division sensith Modet 2160A Sweeps to iioa Dual time base Signal delay fine Vv ays two Signais unre lated In frequency Component tester 949 95 40MHz DUAL TRACE maistae OCS Single Sweep V moda displays two signals unre lated in frequency Component teslar 60MHz CURSORS amp READOUTS DUAL TIME BASE a Cursors and readouts Modei 2260 view sensitivity 23 calibrated ranges main time bese 19 catbrated ranges delayed
37. ha alpha and Q loss The Woofer Tester system includes hardware test leads serial cable AC wall adaptor detailed Instructions and software j PO SOURIO apinsa ll eile iiai pi Y WARRANTY SAME DASSHIPPING High quality Japanese made Patch Cord fea tures color coded RCA plugs on each end for k easy polarity Identification Molded strain reliefs for extra tong life and dura bility Limited availabliity Price Price Part Descrip tion 1 9 10 UP PO 189 070 Red white plugs 1 20 95 PO 189 072 Yellow black plugs 1 20 35 Now s the perfect time to start building your own PC boards A factory buyout enables us to bring you this premium quality copper clad PG boards at unheard of low prices Each board is coated with 0014 copper and is at least 060 thick Limited availability Price Price Part Description u 9 _ 190 UP PO 055 204 6 x 18 single sided 1 50 1 35 PO 055 206 6 x 21 single sided 1 75 1 55 PO 055 222 8 x 24 single sided 2 65 2 40 PO 055 252 6 x 18 double sided 2 25 2 00 900 MHz technology sends signal up to 180 ft through walls floors and ceilings Ideal for use as rear surround speak ers or for adding wireless Sound to every room in the house Full range bass reflex design with built in high power low distortion amplifier Weather resistant cabinet for outdoor use Selectable battery six C size for ea
38. i 1 Year Warranty on All Products Affordable Extended Warranty FREE CATALOG h f NRA L ET 2 Wa FE Ay HTTP WWW ORION ELECTRONICS COM HOME AUTOMATION World s Largest Selection EPROM PROGRAMMING SYSTEM USES PARALLEL PORT 24 28 32 amp 40 PIN 27C AND 25XX 1702 2708 TMS2716 32 32A 64 64A 128 128A 256 512 513 011 010 101 1001 1000 1024 2 10 020 200 1 220 2048 400 1 2 040 080 240 4096 68764 66 FLASH EPROMS 28F256 28F512 28F010 28F020 29C257 29C010 29C040 29F0 10 29F040 EEPROMS 4 NVRAMS 18 24 amp 28 PIN CXX 2210 2212 2804 2816 2816A 2817 2864 2865 28256 28C010 DS1220 DS oa R SERIA PAS 8 amp 14 PIN PLUS CXX idh be 657 2401 02 04 08 16 32 65 2444 i 59C1 1 8001 1 A 9306 46 56 66 8572 82 92 168 9XX SYSTEM INCLUDES ee Hundreds of hard to find automation X 10 and wireless control products Computer interfaces software development toob light ing control telephone systems security systems surveillance cameras infra red audio video control HVAC pet care automa BIPOLAR PROMS 16 THROUGH 24 PINS PROGRAMMING UNIT tion wiring supplies books and videos and much more 74SXXX x 82SX XX Saa Pee PRINTER PORT CABLE MICROCONTROLLER S 8741 42 48 49 8751 WER PACK MANU E C51 52 C52 87C5XXX 87C75X 89C5X 68705 X o a VARE a k 68HC705 68HC711E9 PIC16CXX TMS7742 l ADAPTER REQUIRED DIAGRAMS INC
39. into American living rooms since DVD ROM drives will be able to play DVD video discs But for now the primary focus is on DVD players and movies DVD support ers hope to see at least 200 titles available by year s end Some of the earliest releas es include Twister The Fugitive Space Jam Eraser The Wizard of Oz Batman Blade Runner Raging Bull Interview with the Vampire The Mask and Seven retailing for less than 25 But fewer than 50 titles were available as we went to press and only in seven major markets Chicago Dallas San Francisco Los Angeles Seattle New York and Washington D C Therein lies the potential for format failure Without a large library of videas on hand DVD has little to offer the con sumer And if consumers aren t buying there s little incentive to the motion pic ture industry to produce more DVD discs Looking on the bright side DVD has much more initial support than did the new compact disc format back in the early 1980s And the long and rocky road to market that DVD has already traveled could actually place the format in a stronger selling position Because DVD bridges three major industries consumer electronics com puters and motion pictures each with its own agendas and concerns several sticky issues had to be resolved before a CVD standard could be agreed upon by all three groups and the warring factions within each Of utmost importance was developing a
40. it is fed back to pins 1 7 and 8 The return sig nal to pin 7 is limited by diodes D5 and D6 and the feedback signal to pin 8 is limited by diodes D3 and D4 These diodes distort the signal feedback to pins 7 and 8 Most of the output signal at pin 5 is coupled to the output jack J2 through capacitor C4 Diodes D7 and D8 clip the output signal for the last time Potentiometer R7 and resis Continued on page 75 No Trouble in Troubleshooting his edition of the Circuit Circus is for all of you who enjoy trou bleshooting and solving problems using your electronic knowledge and skill Whether you are just a beginner or a seasoned technician there is something here for you All of the trou bleshooting circuits used in the follow ing examples are both inexpensive to build and simple to use and they could prove invaluable in solving a future electronic problem Automobile Testers Don t let the simplicity of the first three test circuits fool you The test cir cuit of Fig 1 has been around for a very long time and is still being used It is an ideal voltage tester that anyone Can use in troubleshooting the electrical sys tems of most cars and trucks Just con nect the alligator clip to the auto s metal frame and start to probe away The quality of the battery and circuit resis tive losses are indicated by the bril liance of the lamp I ve seen mechanics do an excellent job troubleshooting auto battery problems w
41. m sweating as much as you are this sum mer But if you plan your Christmas list this early in the year as do then you might want to consider a lot of neat products that are on the market for hams In this month s column we will look at several items that you might find interesting Good Antenna Book believe that all hams especially those who like technical stuff should have a relatively recent copy of The ARRL Handbook see December 1996 review in this column This book is known as the bible in ham radio cir cles so buy a new edition from time to time As a guy who writes a lot about antennas and has built more than a few over the years buy just about everything that comes out in that field and The ARRL Antenna Book is a nec essary addition to your bookshelf The 17th edition of The ARAL Antenna Book comes with an antenna software disk that runs on IBM compat ible computers If you haven t seen this book it is a winner For ordering infor mation contact ARRL 225 Main Street Newington CT 06111 1494 Tel 860 594 0250 Fax 860 594 0259 Order No 4734 ISBN 0 87259473 4 30 e mail pubsales arrl org or see a local ham dealer Most technical book dealers carry these books even though they are intended for amateurs and that a lot of pros use them too Das Loudenboomer It seems that there is a never end ing series of loudenboomers on the ham market A recent news release from Ame
42. parts lists amp P C board layouts for own parts to construct our kits KIT BOOK 14 95 9 95 with the purchase of any kit CIRCLE 148 ON FREE INFORMATION CARD NOTE Ali TV Filter Kits are kit 14 95 many of the Rainbow Kits Use your Please add sufficient postage First lb 5 00 Canada 7 00 Additional LB Add 1 00 US FUNDS ONLY We will accept telephone orders for Visa or Mastercard Electronic Rainbow Ind Inc 6227 Coffman Rd Indianapolis IN 46268 ELECTRONIC CALL 317 291 7262 FAX 317 291 7269 RAINBOW INTERNET www rainbowkits com 3 2 DIGIT LCD THERMOMETER WITH DUAL TEMPERATURE PROBES PRACTICAL APPLICATIONS Indoor Outdoor temperature f Temperature of electronic equipment vs room temperature e Furnace or Air Conditioner efficiency return air vs output air e Temperature inside cay outside car e Attic temperature outside temperature SIZE 2 3 4 W x 1 5 8 H x 1 D LCD T1 KIT 34 95 LCD T1C CABINET 9 95 a STROBE LIGHT Do you need an attention getter amp waming light or flashing light for model airplanes Then this kit is for you Use it as an emergency light for your auto radio tower s ES even use it on your bicycle Has a variable flash raze Power requirement 6 or 12v DC eS STi Kit 11 95 A SUPER SNOOPER d BIG EAR Listen through walls hear A conversations across the A room Add a parabolic tea
43. provide little to no benefit There are several types of cochlear implants The single chan nel implant has one electrode located in the cochlea These sim ple implants can help lip reading and provide general awareness of sound Next there is the multi chan nel implant with multiple electrodes in the inner ear to simulate different regions of the cochlea Multi chan nel cochlear implants often make speech recognition possible with out lip reading The most sophisti cated implant is the multi strategy multi channel implant which pro vides the best sound to maximize speech recognition One advanced cochlear im plant system is the CLARION Multi Strategy Cochlear Implant System offered by Advanced Bionics of Sylmar California The CLARION sys tem consists of both surgically implanted and externally worn components The internal compo nents include a single cochlear receiver or simulator implanted under the skin behind the ear and the connecting electrode array of 16 tiny wires inserted into the ear s fluid filled cochlea which when healthy contains thousands of tiny hair cells Implants are done under general anesthesia in two to three hours either on an inpatient or out patient basis Four fo six weeks after surgery the patient is given the external parts of the system the headpiece worn behind the ear a battery powered speech processor usually carried on the belt like a pager or in a pocket a
44. use the popular cross needle design s31u01 93 3 seindog 2661 Isnony n ve Popular Electronics August 1997 co 15KW HF UHE DAY DUMMY LOAD 1 Een Sir Boon a AFF Pj eer o Pi iniia Wi PMT EARS IRC SAAR TLLE Eg UA Fig 2 The MFJ 264 dummy load is a nec essary addition to your ham station These meters read peak forward power reflected power voltage stand ing wave ratio VSWR high voltage grid current and DC plate current The power supply of these linear amplifiers can be set for operation over a line voltage of 90 to 140 volt AC or 200 to 250 volt AC 14 settings of the AC pri mary voltage are possible My own prejudice by the way calls for opera tion of kilowatt and up RF power amplifiers from the 220 volt AC line It requires a special outlet of the sort that electric clothes dryers use but not necessarily as many amperes My lin ear amplifier is connected to a 220 volt AC 20 ampere line that is dedi cated to the amplifier only For information contact Ameritron 116 Willow Road Starkville MS 39759 Tel 800 647 1800 for catalog or 601 323 8211 Fax 601 323 6551 Web http www ameritron com Dummy Load The dummy load is a noninductive resistor used to simulate an antenna when adjusting a transmitter It is the mannerly thing to do when adjusting transmitters linear amplifiers especial ly Or antenna tuning units These devices consist of a noninductive
45. 1 Bii me later for the regular price of 59 95 plus 6 50 shipping amp FULL ELECTRONICS BIBLE that YOUR 900 PAGE ELECTRONICS handling subject to credit approval Signature and phone number teaches you everything from basic REPAIR MANUAL NOW required to process your ordet PO Box addresses must be prepaid Yes 900 Instruction Filled Pages In Wipe Clean Vinyl Binder ay PI o voose tear o STEP BY STEP FIXES PREVENTIVE FORMAT TROUBLESHOOTING MAINTENANCE TIPS Address _ PAGES LIE FLAT INSTRUCTIONS HOW TO USE TOOLS Ci State Zi TABBED CHAPTER TEST EQUIPMENT OF THE TRADE fy P PAGES PRIMER MANUFACTURERS i In Canada please add 10 Overseas orders add 15 foreign orders must be PHOTOS CHARTS SAFETY PRECAUTION DIRECTORY 1 prepaid US funds only CT residents add 6 sales tax Supplements are just DIAGRAMS CHECKLIST PARTS SUPPLIERS 1 35 each plus shipping amp handling They will be sent 45 times a year on a EXPLODED VIEWS ELECTRONICS PLUS MUCH MORE fully quaranteed 30 day trial basis Trey may be cancelled at any tme 33549 REFERENCE GUIDE A eee ee eee oe J CIRCLE 319 ON FREE INFORMATION CARD s9tu01 99 3 seindog Z664 Isnbny WO J pauinbay aue SIAM Z RS EY Networkable NEW RS 232 programmable 240x64 Graphic Display Module Upload your BMP GIF Image Files at 9600 19200 38400 115200 Baud Complete Support for 30x8 and 40x8 Text Docume
46. 1000 Oe as a kit 39 95 a PIN HOLE CAMERA XVS100 r 400 LINE RESOLUTION TV TRANSMITTER assembied 49 95 Use it to test radar detectors in other cars Audio and Video outputs Use with XVC200 VCR from your own vehicle 10 450 tO 10 550 GHz See entire room through Camcorder etc f hand held transmitter Extra high output level f pin sized hole Power cube included f Use with any TV orVCR Uses VHF TV Band Includes an input connector for keyed ama b teur band operation R 16 levels of digital voice changing Sound tougher older or younger female or male NEW Works with regular or multi line phones Connects between handset and phone Nate will not work with cordless or cellular type telephones XVC 2005C with audio amp video input Transmits video amp connectors audio Other models available Up to 100 foot range ff Assembled 169 95 E Z Kit 29 95 aS g XVA 250C _ xps 1000C fi 49 95 55 95 88 108 MHz Z FM STEREO VOICE STRESS ANALYZER KIT TRANSMITTER KIT lige SNOOP KIT SCANNER CONVERTER KIT 800 950MHZ See at a glance if your being lied to Separate level control for both left Dial home from anywhere andhearin Uninterrupted coverage of the 800 to i Subject need not be present Works and sight channels Sy ik se le pandi with voices from recordings TV or Output level circuit with
47. 34 inch PVC pipe as a mounting support inside of which the coax can be run The antenna will fit snugly on the 4 inch PVC pipe and no cementing is necessary You can use a small self tapping sheet metal screw to secure the antenna if desired but it is unnecessary in most cases For ground mounting the coax can be fed through a drilled hole in the support and buried underground for a completely hidden installa tion Make sure J and coax con nectors are at least 6 inches above ground 12 inches would be better to allow for snow and ice If you are Continued on page 76 s31U01 23 3 Jeindog 7664 isnBbny on Q3 Popular Electronics August 1997 i ve a Sa ON ede ne gt a Jo Sa A F ra c E r DTMF FREQUENCY COUNTER d e ne st eile al 7 j ee 2 ee iors an Sew Pm Ee 7 FE A E s A S x Al s Put that old inoperative tone telephone back in service with the aid of this easy to build frequency detection circuit to your home phone network but don t want ta pay a premi um price for a spare phone then maybe you should aHend a Ham fest or Computerfest You ll be amazed at the telephone equip ment that can be found there at rock bottom prices Most of the time the phones have been cleaned up and checked out to make sure they re 100 operational All you need to do is take them home plug them in and you re in business Unf
48. 50 ohm resistor inside a shielded enclo sure Some of them are installed in an oil bath while others are air cooled Pictured in Fig 2 is the MFJ 264 UHF VHF HF Dry Dummy Load which can handle 100 watts for ten minutes or up to 1500 watts for ten seconds Price is a reasonable 59 95 contact MFJ Enterprises P O Box 494 Mississippi State MS 39762 Tel 800 647 1800 for catalog or 601 323 5869 Fax 601 323 6551 Web http www mfi enterprises com Some models like the Drake 2 000 watt unit that have are designed with a cut out on one end to accommodate a small 3 5 inch blow er fan which keeps the load resistor cool at extended high power and high duty cycles that is the ratio of on time to off time oa eee Te eo ae ie Pore Fig 3 Here s the MFJ 346 digital fre quency counter This compact frequency counter is only a little larger than a pack of cigarettes and a lot more useful The dummy load offers benefits over regular antennas for the serious tester First it is a nearly constant impedance over the entire HF frequency range and that is a tremendous advantage Sometimes when you are adjusting an antenna tuning unit or transmitter you don t know whether an anomaly is in the unit or in the antenna especially those which are frequency dependent Second it does not present any appre ciable reactance Impedance is actually a combination of resistance capacitive reactance and indu
49. 984 feet 3 inches A press of the MC button clears the memory The ProTape offers a handy non elec tronic feature as well It allows you to accurately draw any size circle or arc By flipping out a panel that is normally fold ed into the case a small pinpoint is revealed Position that pinpoint at the center extend the tape measure to the desired radius length and insert a pencil through the holes that are punched at evenly spaced intervals on the tape Yes the ProTape 16 is a bit gimmicky But hey some gimmicks work and this is one of them The only easier way we ve found to measure a room is with the ProMeasure reviewed above The ProTape 16 does what it s supposed to do quickly and easily And it s priced rea sonably enough to fit into just about any one s toolbox E On an Even Keel PROLEVEL MODEL HC 200 From Seiko Instruments USA inc 2990 West Lomita Boulevard Torrance CA 90505 Tel 1 800 873 4508 Web http www seiko usa cpd com cpd Estimated street price under 30 Another tool that can be found in every home workshop is a level Whether you re framing a house or hanging a pic ture you need to know if your horizontal surfaces are level and your vertical sur faces are plumb Traditional levels are models of elegant simplicity An air bubble in a curved tube filled with liquid centers itself between two lines on the tube when the device is placed on a level surface If the
50. Analyzer at a very affordable price Great for interference and signal hunting RS232 connect for logging signals to disk Real time display sweep outputs on any X Y scope Variable span and sweep rate Marker function and selectable bandwidth Demods in AM NFM WFM plus BFO for CW SSB modes For instant information use our fax back service at 317 849 8683 405 Or email Scanns www ace coms com http www acecomms com Scanns SOR ae Re COMMUNICATIONS er Line 1 888 445 7717 10707 E 106th Fishers IN 46038 Intemational 317 8427115 Fax 317 849 8794 Email Scannsx www acecomms com CIRCLE 25 ON FREE INFORMATION CARD Ord Se rr yee NETWORK your phones Boost your telecommunication performance Make small business sounds big amp professional FX207 is easy to use and very low cost This small device provides same functions found in big expensive PBX units call transfer conference intercom do not disturb call restriction blocking call pickup call waiting Plus some extras you don t normally find in most regular PBX units such as Voice direct incoming calls with your own message transfer fax automatically Tele remote contro your appliances or computer Record and manage call numbers amp time usage through your computer You might even use it for phone projects control phone operation with PC For home For office For home office FX207 handles two phone lines expanding to seven
51. CARD Symantec Corporation 10201 Torre Avenue Cupertino CA 95014 800 441 7234 541 334 6054 http www symantec com CIRCLE 69 ON FREE INFORMATION CARD appeared in the June 1997 issue of Popular Electronics New Software Windows NT 4 0 is a new operating system that requires updated tools for housekeeping Fortunately Symantec is keeping up with Microsoft and has recently released Norton Utilities 2 0 for NT 4 0 The utilities are for use with NT 4 0 workstations and servers In short these tools let you defragment hard dri ves repair disk problems with both NTFS and FAT monitor resources and maximize performance while eliminat ing problems as they occur The Norton System Doctor runs in the background and it will alert you to any potential problem or performance drain The tae Thy Take a trip with Koala Lumpur Journey to the Edge through an animated comic book world Norton Utilities 2 0 for NT set of tools has an estimated retail price of 99 Valhalla a beautiful golf club in Louisville Kentucky was the chosen location for the 1996 PGA Champi onship Now you can play a few holes at Valhalla right in your very own living room or wherever you have your computer Access Software is the big gest name in virtual golf with a virtual course for your computer to match almost every famous golf resort in the world Valhalla Golf Club combines Scottish style links on the front nine with a
52. CircuitMaker The Virtual Electronics Lab will match your needs We are so confident you will love its performance that we back every copy with our iron clad satisfaction guarantee TraxMaker 2 The Most Affordable Professional Quality PCB Design Tool Trax Maker is a Printed Circuit Board PCB layout program with advanced fea tures such as a built in autorouter 8 layer capability support for surface mount devices and full design rule checking Most importantly Trax Maker provides these features while remaining exceptionally easy to use TraxMaker is a truly cost effective package which is sure to handle your most demanding PCB design tasks TraxMaker can be used as a stand alone product or with compatible schematic capture products When used in conjunction with CircuitMaker TraxMaker completes a powerful start to finish circuit design sys tem TraxMaker provides more power than any other product in its class CircuitMaker CBT Electronics Training Featuring An Award Winning Curriculum MicroCode Engineering and Lab Volt Systems present CircuitMaker CBT com prising 28 analog and digital lessons organized into four modules covering DC Concepts AC Concepts Analog Device Concepts and Digital Device Concepts This is not another one of those textbooks on a computer rather it is an interac uve presentation in an intuitive multimedia CD ROM format providing over 200 virtual labs simulated in CircuitMaker The award winni
53. L2 in a balanced detector scheme The transformer consists of a single toroidal core Amidon Associates 12033 Otsego Street North Hollywood CA 91607 that is triflar wound ie three separate wires are wound together parallel to each other on the same core The dots on the three windings shown in Fig 4C indicate the same ends Although the diodes shown are 1N4148 or 1N914 silicon small signal diodes somewhat better sen sitivity can be gained by using ger manium units such as the 1N34A IN6O or IN270 devices The germa C6 w 12V L1 c5 i 2 5 mH 1 i 5 UD AUDIO C3 OUTPUT Q1 1 001 l MPF102 C4 AUDIO OUTPUT BROADBAND AUDIO TRANSFORMER D1 OUTPUT 1N4148 Fig 4 Mixer circuits for the front end of the direct conversion receiver can be either pas sive or active In A a junction field effect transistor JF ET is used as the autodyne mixer In B we see a dual gate MOSFET is used as the mixer A passive direct conversion mixer is shown in C nium units can be replaced by NTE109 and ECG109 devices from replacement parts distributors IC Direct Conversion Mixers Several different integrated circuits have been used successfully for direct conversion mixers among them the CA3028A and NE602 Figure 5 shows the CA3028A based direct conversion circuit The CA3028A IC1 is basically a DC to RF differential amplifier that has a separate signal input on the cur rent source pin 2 whic
54. Neon lamp type NE 2 or equivalent EE R1 47 000 ohm t4 watt 5 resistor gS Sea 31 SPST momentary push button switch normally open Riadio Shack 275 1556 or equivalent B1 6 volt lantern battery Alligator clips RadioShack 270 amp 349 or equivalent etc 3 E This test circuit is both quick and easy to use Momentarily closing switch S1 applies a DC current to the Get Phi Savings wea You Join Th Electonics B Benefits you ll receive as a member of The Electronics Book Club Club bulletins every 3 4 weeks contain ing exciting offers on the latest books Savings of up to 50 off the regular publishers prices The Main Selection will be shipped automatically If you want another book or no book at all return the reply form by the date specified You ll have at least 0 days to decide If you ever receive a book you don t want due to late deliv ery of the bulletin you can return it at our expense FREE BOOKS through the Bonus Book Program Great Club Terms simply buy 3 more books during the next 12 months with no further obligation If card is missing write to The Electronics Book Club A Division of the McGraw Hill Companies P O Box 549 i Blacklick CH 43004 9918 Alt books are softcover unless otherwise noted Publishers prices showa A shipping handling charge amp sales tax will be added to all orders 1997 EBC T P
55. PREMIER FARNELL C Go fina zs CODE Ss me so1u0oe a JeiNdog Z664 IsNONy aw on Popular Electronics August 1997 ep WEE ie vok aea O CABLE T RS CAL 361 4586 3 8 ESA tok Shall AUP wer e All Equipment New e Convertors amp Descramblers e 30 Day Money Back Guarentee e 6 Month Warranty e Visa MC C O D Welcome KDE ELECTRONICS INC P O Box 1494 Addison IL 60101 Info 630 889 0281 HRS Mon Fri 9 6 CST Fax 630 889 0283 Sat 10 2 CST PC based Front Panel Access Computer 7 11 PC 24 hour Working Computer from 600 For Computer Telephony Server or Home Automation or Network Computer Fanless compact size 9 0 W 7 5 H 6 5 D Handy PC Field Computer from 700 In between of Laptop amp Desktop for the size Using regular CD ROM HD FD and mini keyboard Easy to carry around 10 5 W 11H 6 5 D CELTS E ig ig ig ig LS E R a B eet ee om sinew PLC PC Industrial Computer from 900 Accessibility like PLC Programmable Logic Controller Euro Bus and PC Bus for higher reliability amp better performance 17 W 11 H 6 5 D All above 3 models accept ISA or PCI interface cards and proprietary front panel connecting cards I O A D D A X 10 up to 10A 220V 1000KHz to 1 00GHz Spectrum Analyzer System Up to 500MHz Span Two bands All the advantages of a Spectrum
56. Road Sulte 302 Etobicoke Ontario Canada M9R 1S8 13 Years Intronics Inc Box 13723 612 Newton Edwardsvilie KS 66113 Tel 913 422 2094 Add ANY NEW APPLICATIONS COB amp SMD on gold plated PCB 20 Second Notch Filters Doere ireo Zeinth Test Chip Pre owned software 6V Battery Record TTL Logic Controi tor Pre Recorded Messages Phone Computers ete Type 1 15 x1 15 Type B 0 85 x1 05 Type A 0 385 x0 75 Assembled l to 2 30 each 3 to 9 25 each 10 to 49 S t6 each S0 or more 14 each Video Media P O Box 93 6025 gt p Margate FI 33093 6025 ampuu 954 752 9202 Fax 954 340 5201 l to 2 20 each 3 to 9 S15 each 10to20 9each 21 or more 7 each ll Vaan All COB Design Specialist KSL Microdevices Inc 408 922 0800 FAX 408 922 0629 p jts hold a p O rt O Q 5 ADVANTECH EETOOLS NEEDHAMS DATA VO ICE TECHNOLOGY HILO SYSTEM GENERAL CHROMA MODULAR CIRCUT TECHNOLOGY XELTEK EL PROMAX EMP20 MEGAMAX MEGAMAX4 SIMM SIP TESTER EMUPA CALL ADVANTECH LABTOOL 599 EETOOLS SIMMAX Extensive manuals guide you Pae e Ea a through your development 409 EETOOLS MEGAMAX 279 MOD MCT EMUP R In Sick Or project All programming and 509 EETOOLS MEGAMAX4 49 EPROM 1G TO 512K hardware details explained 369 XELTEK SUPERPRO II 69 EPROM 1G TO IMEG Complete schematics
57. S4 comes into play Always close S4 before closing any of the power on switches of your unit under test UUT so that the lamp s high inrush current will flow through S4 and not the UUT After the lamp lights open switch S4 and let power reach your UUT OUTLET SOCKET FOR UUT 110VAC SEE TEXT Fig 5 With a variable voltage transformer included in this tester you can safely apply power to just about any unknown piece of AC operated electronic equipment PARTS LIST FOR THE LINE VOLTAGE TESTER WITH VARIAC Fig 5 RAi 220 000 ohm 4 watt 5 A resistor S1 SPST toggle switch 110 volts AC 10 amp RadioShack 275 a24 or equivalent 2 SPDT toggle switch 110 volts AC 10 amp RadioShack 275 325 OF equivalent T1 Transformer with variable tap TTO volts AC primary 3 amp or greater see text _Li incandescent lamp 110 volts g a AC 100 watt or greater see text NE1i Neon lamp type NE 2 a Fi Fuse see text Fuse holder lamp sockets AC out bo fet sockets power line cord ett ae mee Pee ary The better of the two AC test circuits is shown in Fig 5 Here we have a vari able transformer or Variac T1 connect ed through a current limiting lamp L1 or through switch S1 to an outlet test socket If you don t have a variable tran sformer on hand and are planning to purchase one go for a 5 amp unit This will give you up to a 500 watt test ing
58. _ LC p E n a SS q j m 1 F i HI T NUM SD maner A Aka Dak saarni inerisi tar Minineniweet Noma Saanman 217 NPIS O inie The Windows based Soltis software uses various measurements to calculate the appro priate corrective lens parameters MICROPHONE HEADPIECE Pi i P ey k 7 5 a4 25 s s T a i x 2 w am 2 W EF E ae J i A TE S t SA i E 7 7 r f i y i k F k 1 a 3 aun 3 i COCHLEAR AUDI TORY NERVE ELECTRODE ARRAY DVANCED Fp ionics In this cross section of the skull the implanted cochlear receiver or stimulator and the electrode array transmits receives signals directly to the auditory nerve thereby bypass ing damaged parts of the auditory system and directly stimulating the auditory nerve The headpiece is mounted adjacent to the implant behind the patient s ear guage skills have been learned Some users say the sounds they hear are similar to those they heard before becoming deaf Others say the sounds are different from those they remember or are sounds that they never heard before Benefits from implants include awareness of speech and sounds around them improved control of the loudness and quality of their voice improved ability to lip read better speech understanding without lip reading and the ability to better use the telephone For individuals with a profound hearing loss even the most powerful hearing aids may
59. also gratifying to be able to make informed decisions as we shopped for materials Even better though was that for the first time ever we completed two major home improvement jobs without having to run back to Home Depot for more supplies And when the job was finished we didn t have any unopened cans of custom miixed paint Jeft over and had just enough carpet scraps to make a few doormats Now if only Seiko could come up with a tool to make painting an easier job W Measure Once Cut Once PROTAPE 16 MODEL HC 500 From Seiko Instruments USA Inc 2990 West Lomita Boulevard Torrance CA 90505 Tel 1 800 873 4508 Web http www seiko usa cpd com cpd Estimated street price under 30 a Measure twice cut once It s one of the fundamental rules of carpentry If you don t take accurate measurements at the outset of a project you ll end up in trou ble sooner or later That s why every tool box contains a tape Measure Yet a standard tape measure leaves something to be desired Even when it is equipped with a tape lock the tape often shifts a fraction of an inch when you try to get close enough to read the measure a e gt Fe I kk aaa eee ment And even the longest tapes won t reach completely around a room to deter mine the amount of baseboard molding required Enter the ProTape 6 electronic tape measure from Seiko It looks like a stan dard tape measure with a
60. and commercial solutions to get ting organized both computer and paper based These solutions all had their strengths and weaknesses but Don t let the small size fool you PalmPilot gives you all the power and features you need to organize your busy life ultimately all failed for one of the follow ing reasons Slow or cumbersome to use e Too much manual labor e Expensive in terms of system resources e Not integrated with my overall information system One of my most important require ments for a PIM was for something to do what call random information man agement Little yellow sticky notes lined and bound lab notebooks and paper file folders just weren t cutting it needed a way of getting things in the computer categorizing them and then later finding them even if the original categorization selected turned out to be incorrect gradually came to realize that what wanted was a dynamic hierarchical hyperlinked full text searchable data base The database had to be dynamic because experience had taught me long ago that no matter how much thought or cleverness applied to devis ing some scheme of classification it would end up changing It had to be hierarchical categories with sub cate gories with sub subcategories and so on because to the extent that any fixed scheme would work found a hierarchical system to be the best A hierarchical system would also be useful for
61. and telescoping antenna GPS receiver and internal patch anten na alphanumeric keypad backlit LCD and rechargeable battery pack To send an e mail message the user types it on the GSC 100 enters the destination e mail address and transmits the message Using a stan dard narrow band VHF radio frequency the user s e mail message goes up to the nearest of the 28 ORBCOMM satel lites and down to a Gateway Earth Station From the gateway the e mail message is routed via local land lines to the desired Internet e mail destination or transmitted to either another GSC 100 or to an ORBCOMM receiver Future service options will allow out bound messages to be completed and incoming e mail to be originated by a voice call or fax Messages are received in the reverse manner with e mail stored until the GSC 100 handset is activated and the satellite queried for unread messages The portable unit will store up to 100 text messages and an address book with up to 150 entries The units integrated GPS receiver features six graphic navigation displays customizable navigation screens a real Continued on page 75 DX LisTENnIng Is it Asia Is it Europe yprus is a ruggedly beautiful Mediterranean island a scenic country of mountains valleys and goid en beaches hilltop castles and old churches with a pleasant California like climate Here on this isle an interesting shortwave broadcaster is back on the air and is being
62. and the ProMeasure wouldn t be much help there The same basic steps are used to calcu late the required amounts of wallpaper which is quoted in numbers of rolls based on the standard size of 20 5 inches wide by l1 yards long carpeting in square yards and heat in BTUs Other factors come into play when fig uring amounts of paneling floor or ceil ing tile and heating and air conditioning BTUs If 4 X 8 foot sheets of paneling are being used you simply input the areas of the walls press memory recall and then press 4x8 If you are installing a different size wall panel you must add another step in the form of a multiplier provid ed in the user s manual For instance if you are installing 2 X 8 panels you would multiply the original results by 2 The default ceiling tile size is 24 feet the manual supplies multipliers for five other common sizes of ceiling tiles As for floor tiles the default setting tells you the num ber of 10X 10 inch tiles required multi pliers are listed for six other sizes ranging from one inch square to one foot square The manual s appendices include conver sion tables for non standard sizes of floor tiles ceiling tiles and wall panels allow ing you to find the proper multiplier for Just about any size materials imaginable While the main factor that determines the BTU requirement for a room air con ditioner is room volume the manual lists a number of other factors the
63. bubble floats off to the right or left you must cor rect the problem before moving on to the next step in your project You can get the results instantly at a glance When it comes to levels we re not sure if Seiko has built a bet ter mousetrapwith its electronic ProLevel Besides the usual bubble indicator the Pro Level features red and green LED indicators and au dible beeps to let you know if a sur face is level Per sonally we can t see how anything could be easier to aw af j Ni _ BS S Sa use than a standard level But those peo ple who can t tell whether or not a bubble is centered can now attempt to interpret colored lights and different pitched sounds with the ProLevel What s more they can judge surfaces in the dark and even those that are completely out of sight Our first thought was How will they manage to fix what they can t see Seiko offers a couple of possible out of sight applications however First you can set the ProLevel inside a parked RV use a jack to level it off listening for the beeps to stop to tell when it is level Or you can place the ProLevel on top of a picture frame as you adjust the picture s level The ProLevel is made of black ABS plastic and measures approximately 7 X 2 X 14 inches Its bottom edge is an inverted V which allows it to rest upon pipes or other rounded surfaces Along its top edge can be found a three posit
64. copy protection scheme that would satisfy the major studios without compromising storage capacity and access times for DVD ROMs In depth discussions of DVD history and technical specifications can be found in the May 1995 and May 1996 issues of Gizmo Because those problems were ad dressed and solutions hammered out before the market release the public wall not be subjected to varied incompatible versions of DVD products Instead the viewing public will be presented with a Continued on page 30 soluadoajy seindod Z664 isn6bny N w Popular Electronics August 1997 Nh d ms ob 12 Zu sgits 2x Digital Video Deck PANASONIC MODEL DVD A300U DVD PLAYER From Matsushita Consumer Electronics Company One Panasonic Way Secaucus NJ 07094 Tel 201 348 7000 Suggested retail price 749 95 At the past two Winter Consumer Electronics Shows we ve been treated to demonstrations of DVD players from several manufacturers Now we actually have our hands on the real thing and so can you as the first wave of DVD players hits the stores All of them offer the digi tal video and audio benefits of the DVD format including 500 lines of resolution Dolby Digital six channel surround sound tremendous storage capacity and flexible convenient playback options The first unit to cross our desks is the Panasonic DVD A300U Matsushita s top of the line model with a built in Dolby Digita decoder Th
65. deals in K Call for prices on electronics today We have thousands of 4 items ranging from unique hard to find p Zenith x parts to standard production components eni Call write or fax today to start your free 2 y subscription to the most unique catalog in i erro N oan i i g wi the industry filled with super values on Tocom surplus electronic and hobbyist type N p yist ty i items If you have a friend who would ioneer r ye i Basie x s ike to receive our catalog send us their Scientific Atlanta name and address and we will gladly x Pioneer forward them a complementary 100 page t catalog 7 KABLEWORKS Why pay more Call today Your 1 source for Oe p unmodified cable TV k ey converters amp accessories Bf k CALL 540 East First Street an Order Line 3 Dayton Ohio 45402 1 800 344 6324 AT A ET Order Toll Free q TO ORDER k FOI IOS IOI OSI SSI Radiotelephone Radiotelegraph FC Commercial License Why Take Chances q l Discover how easy it is to j pass the exams Study with the most Current materials available Our Homestudy Guides Audio Video j or PC Q amp A pools make it so fast easy and inexpensive No college or experience needed The new commercial FCC exams have been revised covering updated Aviation I Marine Radar Microwave New Rules amp Regs Digital Circuitry amp more We feature the
66. fax transmission capability remote e mail access information service reception using a One way pager and wireless e mail when using a two way pager The pocket PC also includes QV Camera Connection software and a financial calculator Two docking stations are avail able optionally Prices Model A 10 499 Model A 11 599 Self Hiding Car Stereo Kenwood USA Corp P O Box 22745 Long Beach CA 90801 offers an alternative to fixed or removable car stereo faceplates Its new line of CD and cassette players including the KDC 9007 shown here features the Mask self hiding faceplate which never leaves the unit yet disappears completely when not in use Two motorized arms lift the faceplate off the unit turn it over and reseat it exposing only a blank panel Users don t have to worry about losing a removable faceplate And the display is larger and easier to read because no space is taken up by an opening for the CD or cassette Instead the opening is behind the faceplate To insert a CD or cassette the user pushes a button and the faceplate slides down and forward to uncover the opening An additional secu rity feature is an optional user selected code that makes the unit useless to any one who doesn t know the code Prices N A Mini Component System Sansui 4251 Burton Drive Santa Clara CA 95054 is celebrating its golden anniversary with the introduction of the Mode AH 7 Dolby Pro Logic mini sys tem styled in champagne g
67. fixed units unless otherwise noted i R11 50 ohm RI 1O0 KMM ohm o RA R4 Rie 47 00 oben i R3 RT R 4 ohm RR 13 000 ohm RO 20 megohm see text An CAPACITORS 3 1 0 01 F ceramic disc CF CS 0 005 HUF ceramic disc C3 82 pP silver mica 4 3 pP silver mica Co 470 uF 25 WY DC electrolytic ADDITIONAL PARTS AND MATERIALS ina 501 4 conductor modular telephone jack ie TAL 327 He quartz watch timing crystal Proioboards IC sockets switch 4 con ductor ribbon cable L4 pin header _ wire solider hardware etc f and g segments The three pos itive Common anode leads of the modules are brought out sepa rately as DISP1 DISP2 and DISPS Remember that DISP4 is not multi plexed along with the other three display modules When you get To the socket pins for DISP4 wire the pins for segments b and cr together and label that line C6 pin 5 Then wire the socket pins for DISP4 segments a d e and S together and label this line IC6 pin 3 Bring the common anode line out separately and label it DISP4 These lines are soldered to the edge con Continued on page 77 91u01 9913 ueindoy 7661 Isnbny un J Popular Electronics August 1997 SCANNER SCENE Of Scanners and Things he company Relm Communica tions has made a fine reputation for itself in the FM two way radio field producing VHF and UHF portables mobiles bases repe
68. in Mexico We ship to your door V amp V PH 713 537 7518 Fax 011 525 361 5996 weedtech iglou com choose mode Prog infrared remote for input or output Telephone Call Restrictor Connects to telephone wall jack Disables alt phones on the line if attempting to either dial a number that has been stored in memory Block mode or dial a number that has not been stored in memory Allow mode Use touch tone phone to enter telephone numbers into memory and ram from any phone on the fine using your password 35 00 RS 232 Digital O Give your home brewed PC Mac pogane a link to the outside wortd 12 O pins can be a reg individually um on off relays triacs etc Respond to button presses switch changes 4x4 matrix decoding with auto debounce Stack up to 16 units on the same serial port for a total E of 1921 0 points 32 00 LOWER YOUR CABLE BILL NOW i ro Ki 513 752 0279 50 MHz Frequency Counter Reads frequency from 1Hz to SOMHz and oanys up to 7 digits on a 18x1 character LCD display Auto range feature provides floating decimal point and automatic placement of suffix Hz KHz or MHz Microcontroller based provides for very small parts count only 2 x 3 big 48 50 DTMF Decoder Logger Keep track of all numbers dialed or 4 entered from any phone on your ine Co
69. letters o o Popular Electronics 500 Bi Gounty Blvd Farmingdale NY 11735 Or you can send e mail t peeditor gemsback com And don t forgat to visit our Web site at httovAvwww gernsback Cor Haves amp Needs bought a couple of really nice clocks at a surplus outlet The only information on them reads Favag Neuchatel Made in Switzerland There must have been some kind of power supply that operated them Each one has a geared wheel that is turned by a small armature that only turns a half turn with each pulse But the first half turn has got to be nega tive It will stop there if you change it to a positive pulse it will go another half turn Each half turn is one second and it looks like 12 volts works it fine but notice it will operate on a lower voltage would like to build a power supply that can change from negative to posi tive with enough current to operate my clocks would need some kind of sup ply that would pulse negative and posi tive every second and am not sure how to build one If anyone can help me out there with a circuit sure would appreciate it THOMAS A BROWN W3AKP P O Box 259 Crownsville MD 21032 0259 Help need an operator s manual for a metal locator The model is XR8 manufactured by Techna Inc El Paso Texas Can anyone help me out Thanks JIM MAZIES 22911 Valley Drive Richton Park IL 60471 have read many articles on GPS and Loran C and
70. low consumption Order N 51 1000 Cable 11 brands VCR 68 brands e TV 77 brands Compact disc and Laser Disc 94 brands DALCO 6 PIECES PRECISION SCREWDRIVER SET Three flat head 2 4x75mm 3x100mm 3 8x 150mm e Three Phillips No Ox75mm No 1x100mm No 1x150mm s iee A screwdriver with three sections precision production with long life to be used e TB ai Available for fixing and combination of comprter io set communicated instrument ratio camera lasses clock watch and kinds of precision units reS 5 98 e ME a Order N 50 1040 New sama a E e_r jer N 50 1040 on E amass 4225 N W 72nd AVE MIAMI FLORIDA 33166 TEL 305 716 1016 FAX 594 6588 CIRCLE 48 ON FREE INFORMATION CARD Popular Electronics August 199 Faas SS ie gt C LICENSED ELECTRONIC TECHNICIAN ese aA 4 As aN oe oa i SSE of m Earn up to 4 ol an hour i and more A ae y SAE P Pam eA ye f 3 J Learn at home in spare time aa H NO previous experience needed No costly school No commuting to class The Original Home Study course prepares you for the FCC Commercial Radio telephone License This valuable licenseis your professional ticket to thousands of exciting jobs in Communications Radio TV Microwave Maritime Radar Avionics and more even start your own business You don t ne
71. mA Qa hs kr SaS Abbreviations x AM amplitude modulation COT Ceniral Daylight Time ChA Central Intelligence Agency OX distance long distance reception DXing attampting or making DX reception EDT Eastern Daylight Time FBIS Fereign Broadcast Information Servis FiM trequency modulation gt ID station identification AIRN Independent Hadio News kKH2 kilohertz MOT Mountain Daylight Time _PC personal computer PDT Pacific Daylight Time R Radio SW shortwave re SWL s shortwave fetoneite TRNC Turkish Republic of Northern 2 Cyprus UTC Coordinated Universal Time VOA Voice of America y oh Sag a g amp ce ee ae TECHNICAL SERVICE DEPT 717 620 4363 EST 1976 which is equivalent to EDT 4 hours CDT 5 hours MDT 6 hours and PDT 7 hours Algeria 15 205 kHz R Algiers Inter national has changed the time of its English service which is now heard 1400 to 1500 UTC If interference is a problem try the parallel frequency of 15 160 kHz Ecuador 9 745 kHz HCJB in Quito still broadcasts on this longtime fre quency Listen in during the evening from around 0230 to 0400 UTC for English language programming Sao Tome 4 960 kHz VOA s relay from this island off the west coast of Africa signs on at 0259 UTC with an interval signal The English language Daybreak Africa program with news and weather fol
72. many variations and countermeasures STEALTH TECHNOLOGY 24 Every known police radar error stealth method and material used to minimize radar and laser reflections tactic and strategy to fight speeding tickets THE PLACAK REPORT 29 How to read and decrypt the magnetic flux reversals on poner credit and debit card magie stripes How to determine the decrypted PIN PAN bank number dates number of uses remaining No hardware needed HIGH VOLTAGE DEVICES 29 Many HV device plans Stun Gun Taser Prod Cane Flasher Blaster Zapper Radar TEE Jacob s Ladder Fence Charger Geiger Counter Fish Stunner much more RADIONICS MANUAL 29 Exciting electromagnetic therapeutic diagnostic devices mostly experimental Descriptions plans availability ROCKET S RED GLARE 29 The most definite and comprehensive source on solid pro pellant survival and amateur rocketry Many plans FREEI 14 How you can get FREE money jobs land housing meals medical Care equipment merchandise much more POLYGRAPH DEFEATS 19 How anyone can tell the truth to a lie detector Many proven methods to beat the test and what to avoid ANSWERING MACHINES OWN ways fip py mate ai machines are hacked to listen to The absolute latest MALT PY tricks and methods Lites being used on the Net to hack soft ware warez and the latest coolest hacking websites Updat
73. metal clip for wearing it on a belt although it s encased in non traditional black with turquoise trim A large LCD readout and five but tons reveal its true nature The ProTape 16 works just like a standard tape mea sure pull out the tape check the mea surement retract the tape But when you have it stretched across a floor you don t have to bend down or lift it up to take a reading and run the risk of the tape retracting slightly Instead you simply push a button and the measurement ap pears on the LCD At first an electronic tape measure seems gimmicky and unnecessary one of those Father s Day gifts bought out of With the press of a button the ProTape automatically adds the case length for inside measurements soiuodjaayy seindod Z664 isnbny N N Popular Electronics August 1997 RQ desperation that never sees the light of day That s what we thought until we used the ProTape 16 Getting accurate measurements is so easy with the ProTape You simply stretch the tape from one end of the surface to be measured to the other and the precise measurement appears in the LCD Press the mr DISP button and the measurement is locked in place before you move the tape measure and possibly the tape If you re taking inside measurements the interior of a closet for instance there s no need to either bend the tape and try to read the figure in the angle or to add the dimensions of
74. more traditional back nine Valhalla supports all versions of Access s Links and Microsoft Golf as well Valhalla Golf Club has a suggest ed retail price of 29 95 If one of your summer projects is to build a new dream deck outside your house then you ll want help in design Ing and building it from 3D Deck 3 0 from Books That Work This disc helps you design single and multi level decks as complex as you want to go For example you can design in open ings for hot tubs and landscaping The program even lets you place furnish ings trees shrubs and more around your yet unbuilt deck to see what dif ferent things would look like A little heip from 3D Deck 3 0 can mean the difference between a nice deck and a magnificent one This one selis for about 50 Kids love pirates it s that simple Now kids ages nine and up can climb aboard an 18th century pirate ship and Sail through history Discovery Channel Multimedia s new adventure game Pirates Captain s Quest takes you on 47 unique adventures and to 34 Caribbean ports Players can board as a pirate merchant or privateer and can even decide to be a male or female captain There are plenty of activities too including sailing sword fighting trading and more Much of the content is historically accurate so Pirates Cap tain s Quest is a learning experience as well as entertaining This voyage has an estimated street price of 29 95 Multimedia is on
75. number of people windows doors arches and lights in the room that require adjust ments along with the amount of BTUs to be added for each In addition the manu al provides a Geographical Factor Map for Air Conditioning which gives multi pliers to use according to region While the ProMeasure has a lot to offer do it yourselfers it can also be used by professionals Realtors should appreci ate the ability to easily measure each room in a just listed house And while we re sure that contractors must have their own established ways of estimating materials requirements we doubt they could be easier than this The ProMeasure even allows profes sionals to determine pricing with mark up and percentage functions If a painter wanted a 40 profit margin on supplies for instance and had determined that paint would cost 150 he would enter 150 press the MU markup key enter the desired profit margin percentage 40 and then press The device would let him know what the sell price should be Similarly if he wanted to realize a 40 return on his investment he would add 40 to the cost of materials We didn t have much use for those functions but we did put many of the oth ers to good use and then some For instance armed with the figures for how much paint and primer we d need il was easy to determine how much more we d spend on 19 99 gallon Benjamin Moore brand compared to the 12 99 gallon B
76. perature measurement interface biofeedback monitor and many other useful interfaces ca BP393 Practical Concise Introduction to UNIX 5 95 If you are using or intend to use the UNIX multi user operating system and want to get the most out of your computer system in terms of efficiency and productivity then you must learn its operating system The book explains how the UNIX operating system is Structured so that you understand what happens when you first approach your computer BP396 Electronic Hobbyists Data Book 5 95 This book provides a wide range of data If for example you require details of a modern five band resistor code or an old color code for a ceramic Capacitor the formula for parallel resistance or basic data on an NESS34AN operational amplifier it is con tained within these pages The subjects covered are numerous and widespread to cover all hobbyist interests ee ee BP343 A Concise Introduction to Microsoft Works for Windows 7 95 The book explains and details How the Works for Windows package fits into the general Microsoft Windows environment how to use the word processor to advantage how to use Microsoft Draw to create and edit graphics and place them in your documents how to build up simple Spreadsheet examples and how single and multiple charts or graphs of different types can be generated And there s much more SHIPPING CHARGES IN USA AND CANADA 0 01 to 5 00 2 00
77. phones and more f FREE LITERATURE 800 223 4542 bm Bectrente Wits Fiane Parts Computers Ameteur Radio Call Debco today for Xe BY vour FREE copy of CABLE TV CONVERTERS Equigment amp Accessones Ls 01u0l 98 9 jeindog 1664 isniny Wholesalers Welcome The Electronic Experimenter s Journal ee Call C amp D ELECTRONICS 1800 423 449 ee ee 1 888 615 5757 M F 10a bp Debeo Electronics 4025 Edwards Rd Cincinnati OH 45209 Lb ll opel g Tre a salle aad Oo w 104 Popular Electronics August 1997 CALL TOLL FREE C amp S SALES 800 292 7711 orders only 3 Se Habla Espanol EXCELLENCE IN SERVICE XK 550 Digital Analog Trainer TK 3000 Elenco s advanced designed Digital Analog Trainer is specially 95 89 f designed for school projects It is built on a single PC board for maxl mum reliability It includes 5 built in power supplies a function gener ator with continuously sine triangular and square wave forms 1560 tie point breadboard area n Tools Included SR 2 Deluxe Saidering tron SH 1 Soldering fron Stand ST 1 Diagonal Fliers ST 2 Long Nose Pliers ST 30 Deluxe Wire Stripper SE 1 Solder Ease Kit ND 3 3 pc Nut Driver Set TL 8 Precision Screw Drivers ST 5 Screw Driver Slotted 3 16 e ST 6 Screw Drivar 1 Phillips ET 10 IC Puller _ SP 2 Solder Pump A professional technician service tool kit Ina ST 20 Safety Gog
78. possible and if any cross modulation or intermodulation is noted adjust R5 to reduce gain Final Assembly When you are sat isfied that all is well you can perma nently assemble the antenna using PVC plastic cement at all joints If you ve not yet decided on a setting for R5 or if you want to change it some time you can drill an access hole in the 3 inch PVC pipe to allow a small screwdriver blade or alignment tool to get at it A g or 3 iInch hole will do Be sure to seal it with silicone rubber or electricians a R1 J4 TO DC BLOCK RECIEVER 1 R2 a3To RECIEVER 2 R N 1 ALL RESISTORS 2 EQUAL VALUE RECIEVER 3 1 4 WATT 5 THRU N 1 CARBON RECIEVERN RESISTOR VALUES NEAREST 5 TOLERANCE Fig 8 If you are one of the many SWLers who own more than one receiver perhaps a signal splitter may be of use to you The signal splitter can be built using a few jacks a metal case and a few resistors putty before outdoor use as water could leak in and destroy the PC board Such sealants are easily removed and replaced The anten na can be mounted almost any where but a location in the clear well away from AC and telephone lines and buildings 30 to 50 feet or more is always the best The small inconspicuous size of the antenna helps greatly in that regard You can also mount the anten na on a post fence railing vent pipe on the terrace efc You can use Another length of
79. require broadcasters to air high definition programming or ini tially to simulcast their analog program ming on the digital channel Broadcasters will be able to put together whatever package of digital product they believe will best attract customers and to make the most productive and efficient use of their channels The FCC specifically mentions non video services including data transfer subscription video interac live materials and audio signals as poten tial uses for the new spectrum The FCC is requiring the affiliates of the top four networks in the top ten mar kets to be on the air with a digital signal by May I 1999 Affiliates in the rest of the top 30 markets will have an extra six months to begin airing digital signals Are you worried about your TV becoming obsolete Don t be and don t put off buying that big screen TV you ve been eying Set top boxes to convert dig ital signals into old fashioned NTSC sig nals will be available They won t provide high definition pictures of course but we don t expect too much high definition programm ng to be available for some time to come Where do more people go for electronics accessories Surprised AE Of course you weren t m amp i li a WEINE adioShack has the accessories people need for all sorts of personal electronics Need z case for your cellular phone a longer lastirg batery a universal remote contr
80. separated or text delimited data such as is found in most popular database programs can be moved into your existing group of records Thus data previously entered into other popular database programs dBase FoxPro Paradox etc can be manipulated and imported into the connectivity software TI s PS 6800 Personal Organizer and its PS 6155 PC Connectivity Kit docking station gives the Organizer power to cre ate and exchange information with a PC Within the necessary limitations of an index card sized pocket organizer Tl has produced a feature rich unit that provides the information portabili ty we all too frequently require Vendor information The PS 6800 retails for 99 95 but the street price be less For another 49 95 you can pickup the PS 6155 PC Connectivity Kit The PS 6800 Personal Organizer and the PS 6155 Connectivity Kit are available from Target Good Guys Circuit City Staples and other consumer electron ic outlets Texas Instruments will take your order directly at 1 800 TI CARES or by Fax at 817 774 6074 or you can write to Texas Instruments P O Box 6118 Temple TX 76503 6118 E DTMF FREQUENCY COUNTER Continued from page 57 nector on the display board After the board is completed solder the wires from one end of a piece of 14 conductor ribbon cable to the edge connector Be sure to keep track of the color coding That cable will connect the display board to the main counter board Plug
81. serious damage to IC Once you check the polarity attach a 9 volt battery to the bat tery connector and switch on the power One of the eight LEDs should come on indicating the compass heading Remember that the com pass must be held or mounted hor izontal to the earth s surface for the correct compass readings Fig 4 A paper label approximately l inch in diameter was placed on the author s Hall Effect Electronic Compass to show the direction indicated by the lit LED That label which is shown heres lightly enlarged can be photocopied and scaled to fit your unit Alternatively you can devise a design of your own or you can even omit it all together The accom panying table shows the direction corre sponding to each of the eight LEDs Like any magnetic compass this one is affected by nearby external magnetic fields which can present a problem when you are trying to use it inside of a car or boat It will be necessary to experiment to find the best operating location in such cases since the outputs of that circuit are digital the compass could also be easily interfaced to mobile robots It would be valuable in that case fo have an absolute direc tional reference when the robots negotiate a room or even a rat maze course Supplement to Popular Electronics August 1997 aa aa ae a Paperback Books cO 100 RADIO HOOKUPS 7 3 00 ae First published in May 1923 this popular booklet w
82. sites that will give you a current credit report just so you ll know what your future landlord will be reading about you For Rent Magazine Online As much as loved the power of the Rent Net site it s always best to have options This next site For Rent Online based on the national maga zine For Rent lets you search through 10 000 rental communities across the country Similar to Rent Net with For Rent Online you can search by state although not all states are represent ed and you ll find fewer choices in each one Once you pick a location you re presented with a pull down menu of the particular suburbs or towns in the area you are searching through A number next to each shows you how many apartments are in the individual areas You can narrow your search by selecting certain prefer ences and then go Results come up on the screen in a form that looks sim There is also a nice little feature that worth visiting Although you will miss the convenience of being able to do a virtual walkthrough of apartments you do eventually have to physically walk through a place you are interested in anyway That s about all for this month If you d like to get in touch with me you can send snail mail to Net Watch Popular Electronics 500 Bi County Blvd Farmingdale NY 11735 or e mail to netwatch comports com W ilar to the magazine s print listings you might have seen this publication ina local supermarket
83. spy broadcast science projects micropower broadcasting broadcast transmit ters amplifiers antennas secret books start ERN own radio station and more Send 1 00 to AN COM INTERNATIONAL PO Box 130 P8 Paradise CA 95967 Paradise UA Yovet ooo ouaaa FREE catalog of fascinating electronics 3D stereo detectors testers tesla iammers robotics much more QUANTUM RESEARCH 17919 77 Ave Edmonton Alberta T5T 2S4 La ee HOME automation ideas ideas construction pro jects speaker switch vehicle detection interac tive control speech recordings more Send 15 00 to CREATIVE CONTROL 937 S Leyden St Denver CO 80224 ALTERNATIVE free energy government sup pressed and electronic weapons Many plans and kits available Catalog 1 00 UNLIMITED UN DERGROUND ELE TRONICS 1839 D West Vistaway 515 Vista CA 92083 nin teach incom net 619 414 6631 VM CB SCANNERS i SCANNERS CB s antennas accessories New Trunck Tracking scanners HPR Box 621136E Littleton CO 80162 i TEACH YOURSELF AT HOME e TEACH yourself basic electronics at home Free information HORAN PUBLICATIONS PE 100 Carbon Street Minersville PA 17954 717 544 6870 ae 2 AUDIO VIDEO LASERS ee VIDEO projectors Sony VPH 1031Q 250 VPH 1030Q 100 VPH 1020Q 100 Ampro Aquastar 250 1 995 00 each 916 354 1990 CABLE TV CABLE TV equipment amp accessories Whole uarantee l saier
84. station that permits exchange of information between the unit and your pc The Connectivity Kit comes with its own special Windows software pack age that installs easily and provides a user friendly fuil featured means of downloading and uploading data between machines The Backup and Restore function alone makes this a worthwhile buy by providing the capa bility to both archive your time con suming entries and prevent the total loss of data if your lost Beyond that the Connectivity Kit Continued on page 77 Hey Couch Potatoes Surf s Up WEBTV INTERNET TERMINAL Manufactured by Philips Magnavox One Philips Drive Knoxville TN 37914 1810 Tel 1 800 597 8790 Web http www magnavox com Price 329 If the cost of a computer is keeping you from getting on the Internet then the Philips Magnavox WebTV terminal might be your gateway to it A TV might not seem like the best way to access the Net After all TV was not designed to deliver text It was designed to deliver moving images something that the Internet doesn t do very well In short however the Philips Magnavox WebTV terminal can do a remarkable job of bringing the Internet to non computer users Let s start out by saying that the 329 price of the box is a little bit misleading While it is possible to use only the sup plied remote control to access the Web it is inconceivable that many people would have the patience to do so En
85. sun Pulsars are moni tored from 322 00 328 60 406 10 410 00 and 608 00 614 00 MHz The hydrogen line frequency at 1420 4 MHz is one of the most important mon itored by the Search for Extra Terrestrial Life SETI researchers The bands from 137 00 138 00 243 855 269 95 400 05 402 00 467 735 470 00 and 1215 1240 MHz are used for satellite data and or voice FM mode downlinks In the 243 MHz band you can copy NFM and WFM mode traffic from military satellites although it s scrambled at times Don t confuse this with the AM mode trans missions from military aircraft The 1215 MHz band is used by the GPS navigational satellites The 467 MHz band shared with land mobile radio services is one of those used by the GOES Geostationary Operational Environmental Satellite Space Shuttle Keep the frequen cies 259 7 and 296 8 MHz AM mode don t let them tell you other wise punched up on your scanner You might just get lucky some com munications have been logged there But keep in mind that the majority of shuttle voice communications are on frequencies and in a mode that cannot be accommodated by your scanner Of course the shuttie also has been reg ularly monitored in the 2 meter ama teur band The Russian MIR space Station it s very active now is most often reported on 143 625 MHz using FM mode oO NEW PRODUCTS Continued from page 14 time track plotter 200 user defined way points five reversib
86. the NMEA data and 0183 format that they output But have never seen anything about an interface and simple software for using that data with a computer would appreciate any information from your readers on an interface for IBM and Commodore com puters and a simple software program Basic DOS etc for using the NMEA data 0183 format Thanks for any help you can provide GEORGE C BOONE KB4GTZ 116 Sixth Avenue Radford VA 24141 a O M o Study at home with the Electronics Technician Best Price The CD ROM costs 249 and comes with ElectronicsWorkbench 4 1 laboratory software simulation package Complete all 23 courses on the CD ROM and receive certifica tion as an Electronics Technician Tuition for the program includes computer based tests tutorial help via 1 800 numbers and the internet me Linh u Boxed DODIRE Public Sector Standards The CD ROM was designed by George Brown The only product of its kind This unique CD ROM based learning College one of the largest and most innovative program includes 23 courses which are community colleges in North America equivalent to a two year Electronics Graduates of the program can continue their Technician program and is recognized as studies towards an undergraduate degree the standard for Certified Electronics through the Minnesota University Bemidji State Technician programs across North America distance education program Purchase the CD ROM Eas
87. the Phantom is for you The Phantom combines the Phazer including the Ticket Rebate Program with a radar detector It s legal in every state except Minnesota Oklahoma Virginia and Washington D C Ask your representative for more details Risk free Thanks to Rocky Mountain Radar speed traps don t make my heart skip a beat anymore Try the Spirit ll the Phazer or the Phantom yourself They re all backed by our risk free trial and a three year manufactur er s warranty If you re not satisfied return them within 90 days for a full No Questions Asked refund The Spirit s lt s Mal Peas 99 9 S amp H The Phazer 199 514 S amp H The Phantom 349 18 S amp H Please mention promotional code 2351 11045 For fastest service call toll free 24 hours a day 800 399 7863 lt 2 2m Sm comtradindustries 2820 Waterford Lake Drive Suite 102 Midlothian VA 23113 soluosoa g seindod 7661 Isnbny Sa LETTERS Whooping It Up Timeless Strobe Light just completed a project that s been on the back burner for almost a decade Here s what happened The February 1987 issue of Hands on Electronics former title of Popular Electronics contained an excellent construction arti cle Variable Strobe Light by Marty Knight ld always wanted to build one and the circuit itself wasn t very compli cated But was stymied by trouble in obtaining all the parts After
88. the Sky and many more exotic locales We rate this one as a twist ed comic adventure Koala Lumpur Journey to the Edge has an approxi mate street price of 39 Last this month is Comfy s Didi amp Boo for children ages 12 to 30 months Didi amp Boo is the latest software for the Comfy Activity Center a special chil dren s keyboard that connects to a PC s parallel port This toy of a key board features large colorful buttons spinning wheels a toy telephone and other goodies APS now Didi amp Boo comes with a special overlay for the keyboard and a host of new activities for very young children Kids can participate in exciting guess ing games role playing make believe and much mare Suggested price for the Didi amp Boo package is 35 E COMPUTER DESIGN jel Now enter the dimensions of the model you wish to design ti Eye a ds De iy wae But They ll Need Their TVs to Find Out That s Where You Conte In fr Fix the TVs that keep Americans captivated hg i L i i z ee a with the help of PHOTOFACT Howard W Sars offers Complete schematics for televisions VCRs and other popularcconsumer products 800 428 7267 3 i i i ii I lie ant i Hi if i http www hwsams com CIRSLE 176 ON FREE INFORMATION CARD s21u04 29 3 Jeindog 7661 IsnBbny Ner Watch Apartment Hunting Online ons for an ap
89. the tape measure case to the measurement on the tape itself The ProTape does the arithmetic for you With a press of the CASE button the size of the case 3 inches is added to the displayed measurement and a plus sign appears in the display A 16 foot tape measure might seem too short for many jobs But what the Pro Tape lacks in length it more than makes up for in brains The device allows you to take cumulative measurements If your living room is 18 feet long for instance you can measure 16 feet enter it into memory by pressing the M button measure the remaining two feet and enter that into memory A press of the MR DISP button then shows the total length of both stored memories That feature comes in handy for many tasks If you need to determine the total linear feet of a room that you plan to wall paper for instance you can measure along each wall storing the measure ments as you go along and eventually come up with an accurate total If you have a stack of wood sitting out in the garage and want to know if there s enough for the shelving project you have planned you can measure each one and the ProTape quickly tallies the total for you It even keeps a running score of how many measurements are stored up to a maximum of 99 After that it keeps stor ing them but stops keeping count It can t however display any of the indi vidual stored measurements The LCD can display maximums of 299 999 meters or
90. things Associate Degree have not changed like re Program and through the desire of CIE s our affiliation with faculty and staff to see Electronics Technician Worid College a their graduates succeed Bachelor Degree That is why at CIE we teach not only Program the hands on practical aspects of if you have the sincerity the electronicstechnology but also delve smarts and the desire CIE can into the why behind today s technol make it happen CIE is already the ogy Why does it work the way it does institute of choice for many Fortune The insights to be gained from such 1000 companies Why shouldn t you a broad rich and comprehensive be next YES Please send me more information on CIE s Associate Degree Program CIE s Career Courses World College s Bachelor Degree Program Name Address State City a Phone Check for G I Bill Active Duty Veteran s3u0442943 Jeindod 7661 isnbny G2 N Popular Electronics August 1997 ww o kasas 3 Fig 2 The Hall Effect Electronic Compass was built on a small printed circuit board measuring 4 by 2 g inches A full sized template of that printed circuit pattern is shown here for those who don t mind etching their own board For those who d prefer not to fab ricate their own board a pre etched and drilled board can be purchased from the sup plier given in the Parts List battery but if you prefer the unit
91. to the corresponding inputs of IC4 the 7447 which coverts the BCD output of IC3 into seven segment code That code is used to illuminate the appropriate segments of DISP through DISP3 Figure 2 shows a simple power supply circuit that can be used to power the DIMF Frequency Count FA ED B C DiSP4 DISP3 DISP2 DISP1 Fig 3 The four 7 segment modules of the display board mounted in a pair of 24 pin IC sockets positioned end to end are shown here Note the locations of the four unused pins on each 24 pin socket when wiring the sockets the 74000 IC are used to handle the current consumed by the com mon anode LED displays The low voltage output of the telephone is applied to IC1 which is used to amplify the signal to the full TIL voltage level The output of the 555 is fed to one input of nano gate IC2 d at pin 13 The other leg of IC1 d is tied to the output of IC a which is used as a gating signal for IC2 d When the gate is high the output of IC is allowed to pass through IC2 d to the input of IC3 the heart of the counter circuit at pin 12 The 4553 has built in multiplex capabilities whose frequency is determined by C2 a 005 uF capac er The circuit uses a 12 volt center tapped 1 2 amp step down trans former whose output after fullwave rectification by D3 and D4 is about 8 volts The 8 volt output divides along two paths In the first path the recti fied output of the trans
92. video one frame at a time with each movement pushing it to right or left results in forward or reverse slow motion play Tilting it to the right or left in play mode advances or reverses the video faster with each subsequent push The front pane shuttle dial can be used for the same purpose The skip buttons found below the joystick are used to skip ahead or back chapter by chapter Most DVD discs contain menus from which you can choose the spoken lan guage subtitle language and select the chapter you d like to view Pressing the MENU button displays the main menu available on the disc submenus can be reached using the joystick select contro Some DVD discs contain more than one movie or version of a movie the TITLE button brings up an on screen list of titles By pressing DISPLAY during play you can select the scene you want to view by its chapter number or by time If there s a particular scene or up to three particular scenes that you know you d like to see more than once you can press MARKER and then SELECT while in play mode to mark and number it Later press MARKER and then use the joystick to select the marked scene number play will resume from that scene The marker func tion is especially convenient if one mem ber of the family is habitually called away in the middle of a movie perhaps your teenage daughter with her marathon The DVD version of Seven allows view ers to jump directly to each of the
93. will resonate with Cl at the desired operating frequency The operating frequency is given by a Oat V Lip lt lt Cl where fis frequency in hertz L1 b is inductance in henrys and Cl is capacitance in farads The exact values required depend on the desired frequency range but typi cal maximum capacitance values for C1 are 50 pF for high HF 140 pF for all of HE and 365 pF for lower fre quencies Of course any of those capacitance values can be used for any of the frequencies in the VLF to VHF range but a suitable induc tor must be provided in each case Keep in mind that the equation is for the ideal case In the real world the inductor and capacitor values are not exact and there will be a small amount of stray capacitance and inductance in the circuit to throw the resonant frequency off a little bit The input transformer can be air wound over a form of your own making or wound on either a toroidal core or a slug tuned coil soludijoa y seindog Z664 sniny Popular Electronics August 1997 da N LO INPUT RF INPUT 14 4 4 AUDIO Ui ayia AUDIO OUTPUT 005 ii 10K 2K R3 5602 Ay 1 2V Fig 5 Shown here is a CA3028 differential amplifier based direct conversion circuit In that circuit one input pin 2 to the amp receives the LO signal while the RF signal is applied through L a L1 b to the amp s differential inputs form both available from Amidon Associates Ano
94. wireless units trom Pelco MVP and Supercircuits Nothing approaches the VidLinks in power picture quality size and value Thank you R Leslie CCTV Installer NY The best Incredible color resolution very easy to use cool P Davis Movie Props CA Actual Size Are you overpaying your cable company You are if SS you are leasing their equipment e Forest Electronics Inc offers a complete line of New Cable Decoders and Converters that are fully Compatible with your cable system All systems come with Remote Control amp Parental Guidance Feature Volume Control is also available e All Equipment is fully guaranteed amp comes with a 30 day money back option For More Information Call Us 24 Hours a Day At 800 332 1996 FAX 813 376 7801 a Converters amp Descramblers e Full 100 mW RF Power Range 500ft to 1 2mile e Crystal Controlled e e High Resolution Full Color B amp W video e e Fully epoxy encased no exposed components Fully assembled only two wires to attach e MONEY BACK GUARANTEE Compatible with Jerrold Scientific Atlanta Pioneer Oak amp Hamlin Equipment BRAND NEW 6 MONTH GUARANTEE LOWEST PRICES Volume Control amp Parental Lockout Available VidLink 100 100mW Power upto 1 4 Mile 199 00 New High Power VidLink 15 15mW Power upto 150 Feet
95. 0 Name Address City NWI State Zip Allow 6 8 weeks for delivery eee Projects for the Garden 6 95 Electronics enters the Garden New excit ing book points out how gardeners can build simple gadgets to promote success where the elements work against you Some of the projects are over under tem perature monitoring dusk dawn switching automatic plant watering warming cables etc An otai Electronics Musical Effect Units 5 95 There is a constant hullabaloo for musical effects projects by the hobbyist community This book provides practical circuits for several projects that range in complexity and are sure to work All the circuits are easy to build and use readily available parts a BP363 Practical Electronic Music Projects 5 95 The text contains a goodly number of prac tical music projects most often requested by musicians All the projects are relatively low in cost to build and all use standard readily available components The project Categories are guitar general music and MIDI 100 NEW TITLES LISTED EACH MONTH CHECK US OUT __ BP385 Easy PC Interfacing 6 95 The built in ports in your PC provide an easy and hassie free way of interfacing your circuits This book provides useful PC add on circuits including the following Digital input output ports analog to digital and digital to analog converters voltage and current measure ment Circuits resistance and capacitance meters tem
96. 0 or SOMHz model HP9150 Bothsets include a handy storage pouch and include an IC test hook adapter for the probe The BNC connector rotates to avoid cable tangle or kink Cable length is 1 4 meters PRICE EACH CATNO DESCRIPTION 1 10 100 HP 9060 Scope Probe Set DC 60MHz 16 49 14 49 11 58 pray 18 62 Etching Chemicals Ferric Chloride A dry concentrate that mixes with water to make pint of etchant enough to etch 400 sq inches of 10z board PRICE EACH CATNO DESCRIPTION 1 5 ER 3 Makes 1 pint 3 50 2 75 SEE OUR ON LINE CATALOG AT a s WWW Cir com Positive Photo Resist Pre E Sensitized Printed TiS Circuit Boards _ These pre sensitized printed circuit boards are ideal for small produc T tion runs They provide high resolu f tionandexcellentline width control Bod _ High sensitive positive resist coated on loz copper foil allows youto go direct from yourcomputer plot or art work layout No need to reverse art Single Sided loz Copper Foil on Paper Phenolic Substrate CATNO DESCRIPTION es ce PP1O1 100mm x 150mm 3 91 x5 91 2 55 1 90 1 70 PP114 114mm x 165mm 4 6 x 6 6 2 98 2 45 1 98 PP152 150mm x 250mm 5 91 x 9 84 5 40 398 3 60 PPIS3S 150mmx300mm 5 91 x 11 81 615 448 4 10 PP1212 305mm x 305mm 12 x 12 yews12 78 1065 8 52 Single Sided loz Copper Foil on Fiberglass S strate 9 ai T LACH CAT NO DESCRIPTION 1 10 50 GS101 100mm x 150mm
97. 0 01 to 30 00 5 00 30 01 to 40 00 6 00 40 01 to 50 00 7 00 50 01 and above 8 50 CO INTERNATIONAL RADIO mm STATIONS GUIDE BP255 mm 9 95 Provides the casual listener amateur radio DXer and the professional radio monitor with an essential reference work designed as a guide for listening tothe complex radio bands Includes coverage on Listening to Shortwave i Radio ITU Country Codes Worldwide Radio Stations European Long Wave and Medium Wave Stations Broadcasts in English and more fixe li 5 S fie i i a ii g a Gre hoped n ETT1 5 75 2 O WIRELESS amp ELECTRICAL CYCLOPEDIA Sas A Slice of history This early amp electronics Catalog was issued in 1918 it consists of 176 pages that document the early history of electricity radio and electronics It was the bible of the electrical A experimenter of the period Take a AA 00k at history and see how far we have come And by the way don t qi try to order any of the radio parts Sam and receivers Shown it s very unlikely that it will be avaitable l SORRY No orders accepted Number of books ordered o j outside of USA amp Canada i Total price of merchandise lt Shipping See Chart icenen SUNOUMN cere cnn l Sales Tax NYS only eere l Total Enclosed All payments must be in U S funds ETO Daaa ee ee ee ee ee eee so
98. 000 Hz the exact BFO frequency depends on the tone that is comfortable to you AM signals can be tuned on the autodyne direct conver sion receiver if the local oscillator is tuned exactly on the carrier fre quency of the AM signal That point is indicated by the beat note squeal dropping to zero i e the zero beat point TO AUDIO OUTPUT Fig 2 In the direct conversion receiver the mixer is tuned to f4 by a resonant tank circuit The local oscillator frequency fa is mixed with f to produce f3 which is then fed to the low pass audio filter which in turn selects the audio difference frequency So what You wonder What s all this superhet stuff got to do with autodyne receivers An auto dyne or direct conversion receiver is nothing more than a product detector that uses input RF tuning that is on the desired frequency of operation rather than the IF and whose local oscillator or BFO tuning is at or near the RF The difference frequency is the desired audio fre quency Direct Conversion Receivers Figure 2 shows the most basic form of direct conversion receiver The mixer input circuit is tuned to fy by a resonant tank circuit A local Oscillator operates on a frequency fo that is only 1800 Hz from f when SSB is received or 300 to 2000 Hz for CW A low pass audio filter selects the audio difference frequency In some CW receivers a narrow bandpass audio filter is used inst
99. 0555 ne SATELLITE EQUIPMENT TS BEST pricing on 18 satellite TV systems for home and RV DSS DISH Network program ming multi room viewing options accessories Call SKYVISION 1 800 500 9264 www sky vision com MINIDISH Satellite systems surround sound big TVs total home entertainment systems Dis count prices STAR VISION DIRECT 1 800 899 9707 8am 10pm Pacific SECURITY e e e ELECTRONIC sales of security systems for home apartment or business Will send information Call 812 295 4240 i BUSINESS OPPORTUNITIES a START your own technical venture Don Lan caster s newly updated incredible Secret Money Machine Il tells how We now have autographed copies of the Guru s underground Classic for 18 50 SYNERGETICS PRESS Box 809 C Thatcher AZ 85552 520 428 4073 Visa MC _ INVENTIONS ideas new products Presentation to industry exhibition at national innovation expo sition Patent services 1 800 288 IDEA millions in scrap gold from old electronics computers Circuit boards jewelry 24 hours 603 645 4767 645 4700 o omamassa SATELLITE Television Pays 18 minidish sales force needed STAR VISION DIRECT 1 800 899 9707 8am 10pm Pacific AM are EASY work Excellent pay Assemble products at home Call toll free 1 800 467 5566 Ext 5730 WE CARRY A FULL LINE OF CONVERTERS AND DESCRAMBLERS COMPATIBLE WITH ST MAJOR BRANDS INCLUDING 30 DAY
100. 23 250K 47 VOLUME R14 50K C16 R9 b 100K TREBLE C22 Fig 2 This mini CD player stereo amplifier works better than commercially available units Equivalent substitutes for the LM386N 1 ICs are the Thompson K9210 chips Mini Stereo Power Amplifier The circuit in Fig 2 is a mini CD player stereo amplifier that works bet ter than commercially available power amplifiers The circuit requires only a few parts and uses the inexpensive National Semiconductor LM386N 1 low voltage audio power amplifier IC This circuit features tone controls so you can separately alter the amount of bass and treble at each output The headphone output channels of the CD player are fed to amplifier input jacks J1 and J2 The jacks are coupled to the non inverting inputs at pin 3 of IC1 and iC2 by way of the resistor capacitor series connection R4 C4 and R16 C18 respectively The input signals are filtered by C1 R2 and C2 R1 for the left channel and by LEDI s SPKRI1 PHONES 8Q R10 A 100K SPKR S2 a R11 J3 HEADPHONE JACK A R17 100K C15 R14 and C16 R13 for the right channel The dual volume control R3 and tone controls bass R6 and tre ble R9 also act as filters in the nega tive feedback loop Capacitors C3 and C17 which are connected to each side of the volume control boost low fre quency signals for each channel The amplifier outputs of IC1 and IC2 are correspondingly coupled to
101. 2630 w tracking generator 2995 500MHz Series Model 2615 1595 Modei 2620 w tracking generator 1895 V 422 40MHz Was 965 V 1065A 100MHz w Cursors NOW 765 Save 200 Was 2139 NOW 1565 Save 574 E ERR SF ts W 525 10MHz w Cursors V 1560 100MHz Was 1790 Was 1355 NOW 955 Save 400 NOW 1490 Save 300 99B 2095 Call or write for complete specs 552 50MHz Was 1195 V 1565 100MHz w Cursors NOW 850 Save 345 Was 1960 NOW 1595 Save 365 V 555 50MHz w Cursors hi Was 1375 NOW 975 Save 400 V 252 20MHz 419 w WE WILL NOT BE UNDERSOLD C amp S SALES INC fx 15 DAY MONEY BACK 2 150 W CARPENTER AVENUE GUARANTEE i aa Rae SaaS E WHEELING IL 60090 FULL FACTORY WARRANTY p FAX 847 541 9904 847 541 0710 PRICES SUBJECT TO CHANGE WITHOUT NOTICE IL Residents Add 8 Tax http www elenco com cs_sales CIRCLE 32 ON FREE INFORMATION CARD so1u0ij0e 9 Jeindog Z664 ysnBny on Popular Electronics August 1997 D PANASONIC 10 PC 20 PC TZPC1453G2 63 61 Top of the line converter featuring sleep timer parental lock standard HRC switchable last channel recall favorite channel memory and 83 channel capable TZPC1003 49 44 42 One of our best selling converters featuring sleep timer parental lock last channel recall favorite channel memory and 80 channel ca
102. 3 91 x5 91 3 90 2 98 2 60 S114 114mmx 165mm 4 6 x6 6 4 80 349 3 20 GS152_ 150mm x 250mm 5 91 x9 84 869 5 98 5 78 GS153_ 150mmx300mm 5 91 x11 81 10 20 7 20 680 GS1212_ 305mm x 305mm 12 x 12 ew 18 88 1573 12 59 Double Sided loz Copper Foii on One aT CEEACH CAT NO DESCRIPTION 1 10 50 GD101 100mm x 150mm 3 91 x5 91 5 07 3 68 338 GD114 114mm x 165mm 4 6 x 6 6 5 95 429 3 99 GD152 150mm x 250mm 5 91 x 9 84 10 47 7 39 6 98 GD153_ 150mmx300mm 5 91 x 11 81 11 95 869 8 30 GD1212 305mm x 305mm 12 x 12 NEWI 22 09 18 35 14 68 Developer This productis used as the de veloper on our positive photo resist printed circuit boards Inctudes instructions 50 gram package mixes with water makes quart gt EN A PRICE EACH CAT NO DESCRIPTION l 10 25 POSDEV Positive Developer 95 80 S50 Etching Tank This handy etching sys tem willhandle PC boards up to 8 x9 two ata time Ideal for etching your PCB s systemincludes anair pump for etchant agitation a thermostatically controlled heater for keeping etchant at optimum A temperature and a tank that holds 1 35 gallons of etchant A tight fitting lid is also supplied to prevent evaporation when system is not being used Typical etching time is reduced to 4 minutes on 1oz copper board REDUCES CAT NO DESCRIPTION ETCHING TIME 12 700 Removeable Hard Drive Racks The ideal solution for protecting highly sensi tive data Or buy one computer and allow individu
103. 3A SYNC Out arb waveform RS232 IEEE 488 option Al TEL 800 526 ALFA 2532 609 897 1135 Call Write Fax Email for FREE CATALOG FA ELECTRONICS FAX 609 897 0206 Visa MC AMEX COD PO Accepted OM Welcome PRINCETON NJ 08543 Email alfa0168 aol com ___1 Year Warranty 2 Years for Instek 2 probes x1 x10 2 probes x1 x10 OS 305 209 95 MHz One Channel OS 310 324 95 10 MHz One channel DM 8055 649 95 54 det 0 006 basic accuracy luV imh InA resolution dBm auto REL min max DM 8055G 889 95 GPIB Same funct as DM 8055 Analog Meters Display PS 1830 209 95 I8V 3A PS 1850 219 95 18V SA H PS 3030 224 95 30V 3A noes PS 6010 209 95 60V 10A 1409 95 PR 3060 314 95 30V 6A PR 6030 314 95 60V 3A PC 3030 499 95 PC 3030D 549 95 PPS 6620G 1 099 95 PPT 1830G 1 399 95 PPT 3615G 1 399 95 Frequency Counters FC 8131 469 95 1 3GHz FC 8270 629 95 2 7GHz UC 2010G 294 95 Operating Rating voltage 3 60V current 6mA 60A power 300W temp 0 40C operate 10 70C store Over voltage over current over power protection Operation mode constant voltage current resistance Mit Transient Gen Frequency 1Hz 1kHz duty 10 90 High Resolution 20mV 0 2mA 0 3mQ Digital Meters Display PS 1830D 219 99 18V 3A PS 1850D 244 95 18V SA
104. 4 Gold sound card system is the first major change to the Sound Blaster line in quite some time yet it still offers gen 8 uine Sound Blaster compatibility The To eliminate noise from the audio circuitry the AWE64 Gold has no amplifier or IDE controller on board _ Instead the AWE64 Gold has a SPDIF Sony Philips Digital Interface output for a direct digital connection to DAT recorders or other equipment The non Gold AWE64 like the AWE32 before it still has the amplifier and IDE controller The AWE32 like most other sound cards is a 32 note polyphony sound card that can play 32 notes simultaneously But every single sound gun shot flute note or whatev er needs a separate note or voice Complex compositions where multiple notes are played simultaneously and Watch BY MARC SPIWAK TECHNICAL EDITOR WINDOWS MAGAZINE multiple instruments are layered on top of one another can use up the 32 notes rather quickly Electronic musicians and software developers now have the option of using the AWE64 s 64 voice polypho ny Half of the AWE64 s voices are pro vided by an EMU8000 wave table synthesizer that s now been complete ly integrated into the AWE chip The other 32 voices are produced by Creative WaveSynth WG a software wave table synthesizer This synthe sizer lets the AWE64 remain compati ble with 32 note MIDI sound boards and lets 64 voice MIDI files be played on any Windows MIDI playe
105. 63 37 6 95 6 10 5 41 RH60 4 4 4 Ib Spool 031 60 40 24 00 2190 17 92 Power Supply Regulating Kit for CA H34 This simple RH60 TUBE_6 02 Tube 031 60 40_ 9989 kit is designed to fit onto the back of the CA H34 CCD PRICE EACH camera It resolves the problem of hooking up the camera to e CCD Camera IR Responsive As Low As 85 e This black and white monochrome CCD Cam te era is totally contained on a PCB 70mm ii 3 x 46mm The lens is the tallest compo nent on the board 27mm high from Ys the back of the PCB and it works apiid T Tames with light as low as 0 1 lux It is IR at eg a an Responsive for use in total dark jk ness It comes with six IR LED s on Doara IT CONNECTS TO any standard monitor AUX or video input on a VCR or through a video modulator to a TV Works with a REGULATED 12V power supply 1 1V 13V Hooks up by connectiong three wires red to 12V black to ground power amp video and brown to video signal output CATNO DESCRIPTION l 5 an UNREGULATED supply which damages the camera by CA H34A PCB Mounted IRCCD Camera 99 00 85 00 providing safe regulated power from any 2V 14V DC supply Power Supply Regulating Kit _ 6 95 __ It also provides regulated 12V DC from a 12V AC source mI SEE OUR ON LINE CATALOG AT mI HTE www cir com ee CIRCUIT SPECIALISTS INC RECEIVE OUR ee ot ethene CATALOG SINCE _ 1971 and supplies We ve got I C s capacitors resisto
106. A Kit 109 Asm 159 sea Soe A Le eH 4s 7 Sa 180 Motion 8 16 Hobby Servo Controller Futaba J Compatible Infrared Receiver Included with SV16 upgrade Designed for all animatronic applications SV8 Kit 39 Asm 54 SV16 Upgd Kit 19 Asm 29 IRTA Kit 24 Asm 39 Popular Electronics August t997 co _ASB Serial Booster Gives your AS 232 Port the Power It Needs to Drive 16 NCD Devices RSB Kit 12 On Line Catalog J members aol com ncdcat index aieiaa E mail necdryan aol com 40d BES CE2 Sy ajbuig e WOU SadiAag QON ISOW aleuady 07 New and Pre OwnN ed Test Equipment Goldstar Pre Owned Oscilloscope Specials B K Precision 1476 10 MHz 229 00 Great Starter Scope Tektronix 465 100 MHz 599 00 Tektronix 465B 100 MHz 699 00 Tektronix 475 200 MHz 799 00 Tektronix 475A 250 MHz 899 00 e The Industry Standard of Oscilloscopes e Dual Channel Calibrated Delayed Sweep e Professionally Refurbished e Aligned amp Calibrated to Original Specifications e6 Month Warranty The Longest Available Model OS 9100P 899 00 Full 100 MHz Bandwidth e Dual Channel High Sensitivity e TV Synchronization Trigger e Calibrated Delayed Sweep e Includes Two Probes 2 Year Warranty _ertea fg BK PR S Heo maa XTEC folate Jy genio Model 4040 499 00 20 MHz Sweep Function Generator e 0 2 Hz to 20 MHz 5 digit LED Display 1 EW e Burst Operation www fotronic com e Externa
107. AC V A Q hFE diode continuity 863E 469 Light Adapter 49 95 DMM 124 69 95 Electricalt Temp DC ACV capacitance freq 3 phase diode contin DMM 125 54 95 Autorange bar graph DC i diode continuity beepe Anemometer 179 95 Anemometer adapter And More 89 95 867E 659 4 Dual Trace Component Test 6 CRT X Y Operation lt 4 TV Sync CH2 Output Graticule Illum 2 Probes x1 x10 SG 4160 124 95 100kHz 150MHz sinewaves in 8 ranges 100m V at 3SMHz PS 200 20 MHz Dual Trace 339 95 SG 4162 229 95 Generate same signal PS 205 20 MHz Dual w Delay Sweep 429 95 as SG 4160 but with int counter 150MHz PS 400 40 MHz Dual Trace 494 95 Audio Generator PS 405 40 MHz Dual w Delay Sweep 569 95 PS 605 60 MHz Dual w Delay Sweep 769 95 PS 1000 100MHz Dual Trace 999 95 AG 2661 124 95 0Hz 1MHz 0 8Vpp 2 sine 0 10Vpp squarewave AG 2603 229 95 Same as AG 2601 but with additional counter and digital display Function Generator FG 2100A 169 95 2Hz 2MHz 5m V 20 Vp FG 2102AD 229 95 same as FG 2100A but with int counter and TTL CMOS output FG 2103 329 95 Sweep 0 S5H2 SMHZ linear log VCG GCV and int coun Triple Output One fixed SVDC 3 Amp output Parallel to double current output PS 8102 amp PS 8103 only Digital Scope DS 303 30MHz Digital 20 Samples sec 849 95 e DS 303P RS 232 interface 30Mh
108. Add 5 total S H US Canada ai ac nduealional pupone ogly Blasters Security Surveillance x EM Weapon Postal M O is fastest VISA MCOK COD 49 999 add 7 Route mieaaons Pea Rife Crystal Radionics Bug amp Tap Detectors Blasters ayers Lineman s Handsets x ore Color Boxes G A pS E gt i ra T AWA Voice Disguisers amp ESS Infinity Devices ay DTMF Decoders x Child Finder x Panic Button I eI o A A J RM ETERS Slot Machine Masters amp Subliminal Mixer W hia Amps Ultrasonic Infrasonic TENS Hear As reported on 60 MINUTES How devices n ing Assistors amp Electronic Dowsers Shriek can slow down even stop watt hour meters f 22 gt Modules Ghost Detectors Vortex Genera ee while loads draw full power Device plugs P saas Tinaas Catalog Today into one outlet and normal loads into other outlets Describes meter creep overload droop etc Plans i A U TO a ATi Cc Ai IHE LG MANUAL External magnetic p applied to meter to slow down TELLE R fff eS egg and stop power meters while drawing full loads Plans 25 MACHI NES a KW HR METERS How watt hour meters work calibration error modes y i many ANSI Standards etc Demand and Polyphase Meters Experimental Ay M primes auses eee results to slow and stop meters by others A real eye opener 25 100 methods detailed include Special All 3 above Only 59 Physical Reg E cipher PIN compromise card ig z counterf
109. Both of them have one tube But beneath the photograph of the Aeriola Senior Type RF on page 11 is a Single tube unit that contains an RCA Radiola Senior label Also on page 11 he shows a Radiola Senior Type RS which is a two tube unit These photographs combined with my grandfather s papers and retirement speech seem to suggest that the Type RF was originally called an Aeriola Senior later called a Radiola Senior and later improved to a Type RS but still called a Radiola Senior My remain ing question is why my grandfather called the RS an Aeriola Senior Because he typed his speech and did not save the draft copies do not know whether this was intentional or not In any case have never seen the RS called an Aeriola by anyone else have two of the Type RS Seniors which were my grandfather s Neither of them has any label and there are no signs of labels ever having been installed assume he purchased them through Westinghouse s surplus sales to employees policy would be very interested in hear ing from anyone who can shed light on the Aeriola Radiola question If find more information on this arcane mat ter will follow with another letter David E Booth 318 Fairfield Avenue Westminster MD 21157 5913 Latest Lindsay Reprints Lindsay Publications long a source of reprints of early technical books has scored again with the release of 1928 Radio Trouble Shooting by Enno R Ha
110. C Q diode Const voltage current mod Voltage regulation lt 0 01 FG 8015G 189 95 Sweep Dual CH Delay sweep 0 02Hz 2Mhz no counter ALT trigger trigger lock Dual CH X Y operation 1 mV div sensitivity ImV div sen delay line Z axis input CH1 output Auto track serial parallel Current regulation lt 0 2 100point program PPS ser Sine Squ Tri pulse Ramp 1000V 20A 0 5 accu Zaxis input CH1 output TV syn trigger level Const volt current mode PS 2 analog or digital dis Opoint Program PPT ser FG 8016G 239 95 DM 8040 339 95 3 4 det Hold off TV syn lock 4 analog or 2 digital display PR 2 analog or 2 digital dis Auto serial parall PPT ser 0 02Hz 2MHz w counter ACV to S0kHz true rms Auto track PPT series IEEE 488 2 and SCPI compatible command set optional PPS 1860G 1 099 95 PPS 3635G 1 099 95 Pulse function generator FG 8017G 249 95 Sweep Sine Tri Squ TTL CMOS 0 02Hz 2Mhz FM mod FG 8019 399 95 Sweep 0 02Hz 2MHz w counter INT EXT AM FM mod FG 8019 209 95 0 02Hz 2MHz w counter FG 8050 499 95 Sweep 0 05Hz SMHz w counter INT EXT AM FM mod Synthesized Function Gen Linear log sweep Self Test and Software Calibration PS 3030D 254 95 30V 3A Output sine tri square Arbitrary modulation Meet UL CSA IEC Safety regulation PR 6030D 399 95 60V
111. COMPUTERS Tiny computers run PBASIC programs Visit us on the World Wide Web B aa You ll Find e New Product News Application Notes Software Updates Customer Apps om anne al comm pi aay jag a l ees i Oe tee tira lel rf seater af PKC evvelopenark toate and BARIC Stam ingiebeard Compre Weleeme to Pereas Ine Paran inc produton programmers and for POCHIC i mkorecertretiern and BASIC Stamps whieh ere liny PIC band computers Pat run BAINC programe BFE The last sow monta have mepagimeny changes at Parati Find oi roots http www parallaxinc com BASIC Stamps are component sized computers that run PBASIC programs They have 8 or 16 I O lines which can be used for a variety of digital and analog purposes And their language is both familiar and extensive including FOR NEXT IF THEN and GOTO as well as XOUT SHIFTOUT DTMFOUT and other special com mands If you ve heard about BASIC Stamps but never took the plunge now you can do so for less We now offer a popular Starter Kit ranging from just 79 to 149 The kit contains everything you need to get your feet wet with BASIC Stamps FaxBack 6002 1 0 instructions for pushbuttons potentiometers pulse measure ment PWM serial I O sound ete BS1 I Module 34 BS2 IC Module 49 8 1 0 lines 16 1 0 lines 80 instructions max 500 instructions max 2000 instru
112. COMPUTERS HELP Fi Build a gadget that detects the direction of the Earth s Magnetic Field Active Antenna for 100 kHz 30 MHz Give your receiver added pull to catch weak signals Experiment with direct conversion receiver circuits Keeps You in Tune with Trends in The Laser Fridge y Consumer pore Generate cold from a device that can create extreme heat A GERN pe pe Mn od Wn vn NAR ut we CALL 800 263 5552 Better Designs Faster blais ai aeie f 1 me ep Be NEW Electronics Workbench Version 5 with analog digital and mixed A D SPICE simulation a full suite of analyses and over 4 000 devices Imports SPICE netlists Exports to PCB layout programs Still the standard for power and ease of use Still the same low price Join over 75 000 customers and find out why more engineers and hobbyists buy Electronics Workbench than any other SPICE simulator You ll be working productively in 20 minutes and creating better designs faster We guarantee it Check our web site at http www interactiv com for a free demo 30 DAY MONEY BACK GUARANTEE VERSION 5 0 FOR WINDOWS 95 NT 3 1 Upgrades from previous versions 79 SV SV WY saan p COMI OCI oats COIN GDI Tene vec once py High End Features TRUE MIXED ANALOG DIGITAL FULLY INTERACTIVE SIMULATION ANALOG ENGINE DIGITAL E
113. D WIRES FLATWASHER SOLDERED TO CONNECTOR 8 FLANGE ix 3 4 PVC COUPLING WITH STOP NUT 3 8 24 NUT ey ne ee ew NUT 3 8 x 1 FLATWASHER aS at CONNECTOR WITH FLANGE Fig 5 The completed preamp board along with its antenna wire is housed ina length of plastic PVC pipe The board is first mounted into a 31 inch ID PVC coupling with stops using a pair of 3ig X l inch flat washers and mounting hardware See text for complete construction details Once the board is completed put the circuit to the side and pre pare the plastic PVC pipe that will house the preamp The board is mounted into a 3 inch ID PVC coupling with stops using a pair of 3 3 1 inch flat washers and mount ing hardware The coupling acts as a water shield for F connector JI Note Use gray or white PVC fittings Black fittings may be ABS type and possibly the carbon pigment used could cause RF losses Do not use metallic fittings Figure 5 shows details of the preamp assembly and its PVC housing First a nut is thread ed onto the F connect to serve as a back stop Then the washers are positioned one on each side of the coupling stop and the F connector is threaded though the washers and secured with a nut Cut a piece of 3 inch OD PVC pipe to an appropriate length to cover the board see Fig 5 The open end of the pipe is outfitted with another 3 inch pipe coupling the coupling mates with a reducer and the reducer mates with a lengt
114. Fig 7 shows a simple and safe method to determine this resistance You might ask why not use an ohmmeter and be done with it A few of the newer digital ohmmeters might be safe to use but even some of these can produce sev eral milliamperes of current in the low ohm scale Such a current could cause the meter s sensitive needle to peg full scale leaving a permanent kink in the needle A somewhat safer way to use an ohmmeter is to connect the nega tive probe of the VOM to the positive meter terminal and the positive probe to the negative meter terminal This method will peg the needle on the low end and in most cases the needle will not sustain any damage But why take a chance on messing up a good expensive meter This circuit shows how to do it the safe way Set both potentiometers R1 and R2 to their maximum resistance rotation and connect the meter under test to this circuit Adjust control R1 for a full scale reading on the meter Press momentary switch S1 and now adjust R2 for a half scale reading on the meter Release switch S1 and mea sure the resistance of R2 This value will be the same resistance as the in ternal movement of the meter Murphy s Circuit If you have been around the elec tronic scene for a while it is almost assured that you ve been exposed to our nemesis Mr Murphy One game Murphy really likes to play is to add a pinch of intermittence to an otherwise perfectly good operating circu
115. For Rent Online lets you also pull up floor plans and additional pictures of most apartments as well though Also like Rent Net this site lets you see maps of the area you are considering in and gives you an opportunity to contact the agents directly involved with each place lets you listen to a real audio descrip tion of the apartment While what you hear is the type of sales pitch you might imagine it to be it is interesting having this multimedia option HOT SITES Rent Net fifo www rent net For Rent Magazine Online hito aveapisforrentcom Overall this site isn t as innovative as Rent Net but there are still different apartments to be found here than at the other site For that reason alone it s It s a computer generated cow Chip beef Do you get it Chip beef Turn Your Multimedia PC into a Powerful Real Time Audio Spectrum Analyzer Features 20 kHz real time bandwith Fast 32 bit executable Dual channel analysis High Resolution FFT Octave Analysis THD THD N SNR measurements Signal Generation Digital Filtering Triggering Decimation Transfer Functions Coherence Dynamic Data Exchange DDE Time Series Spectrum Phase Spectrogram and 3 D Surface plots Real Time Recording and Post Processing modes Applications Distortion Analysis Frequency Response Testing Vibration Measurements
116. G8HC11 based system All models come with 739 STAG ORBIT 32 m 32K Byte ROM 32K Byte RAM 2 by 16 Liquid Crystal Display 4 by 5 Keypad Digital Analog and Serial I O Interrupts timers chip selects 26 pin expansion connector Built in Logic Probe Power Supply can also be battery operated Powerful ROM MONITOR to help you program Connects to your PC for programming or data logging cable included Assembly BASIC and C programming varies with model Program disks with Cross Assembler and many well documented program examples User s Manuals cover all details over 500 pages e Completely assembled and ready to use Source code for all drivers and MONITOR Optional Text Book F nae Call for Free Info Pack or see WEB at http www aesmicro com AES 714 550 8094 FAX 714 550 994 Call 1 800 730 3232 CENPP AES 970 W 17TH STREET SANTA ANA CA 92706 USA Everything you need From 279 Money Back Guarantee Easy to use software tha available for MCU s 874X 8 FM BROADCAST TRANSMITTER BOARD Assembled unit is crystal controlled with ALC 2 1 Compressor and Stereo Generator Bandwidth is 75MHz to 125MHz with 500m W s RF power Stereo version 295 US Mono version 245 US Kits avail ablel For catalog of video surveillance and profes sional broadcast equipment send 2 00 to Wavemach Communications 320 Dixon
117. John Yacono 67 Circuit Circus No Trouble in Troubleshooting Charles D Rakes 73 Computer Bits Getting Organized Jeff Holtzman DEPARTMENTS 4 Editorial 6 Letters 14 New Products 79 Popular Electronics Market Place 110 Advertiser s Index TIOA Free Information Card Popular Electronics Lorry Steckler BAF CET editat i chiet ond publisher EDITORIAL DEPARTMENT Julian Martin editor Robert Young jechaical editor Edward Whitman ossociole editor Teri Scaduta ossistont editor Evelyn Rese editorial assistant Joseph J Carr K4IPY contributing editor Mare Ellis contributing editar Jeffrey K Holtzman contributing editor Don Jansen contributing editor _ Charles D Rakes contributing editor Marc Saxon contributing editor More Spiwak contributing editor John Yocono contributing editor PRODUCTION DEPARTMENT Ruby M Yee production director Ken IFE desktop production director Lisa Baynon desktop production Kathy Campbell production assistant ART DEPARTMENT Andre Duzant an director Russell C Trualson illustrator CIRCULATION DEPARTMENT rosters Lombarda irculnadien monger Ging L Gallo circulation assistant Michale Torrillo POPULAR ELECTRONICS bookstere BUSINESS AND EDITORIAL _ OFFICES Semsback Publications Inc 500 Bi County Bled Farmingdala WY 1735 156 293 3000 FAX ho le 299 311S President Larry Steckler SUBSCRIPTION CUSTOMER SERVICES ORDER ENTRY 1 800 827 0483 fd AM
118. LUDED E E SOFTWARE READ VERIFY PROGRAM COPY DISK FILE LOAD SAVE CHECKSUM FULL SCREEN BUFFER DITOR W 20 COMMANDS READS HEX S RECORD AND BINARY FILES 2 FAST DEVICES PROGRAM IN UNDER 20 SEC Se et RUGGED 9 X6 X3 ENCLOSURE W HANDLE AR SSI 07 0 MADE IN USA 1 YEAR WARRANTY VISA MAS TERCARD ANDROMEDA RESEARCH P O BOX 222 MILFORD OH 45150 513 831 9708 FAX 513 831 7562 Home Automarion Systems Inc Questions 714 708 0610 Fax 714 708 0614 e mail catalog smarthome com http www smarthome com smarthome 24 Hours 800 762 7846 Synthesized Signal Generator Clean sinewaves DC 20 MHz with 001 accuracy an 1 Hz steps DC Offset RS232 remote control Onna Arbitrary Waveform Generator em Quantity 40 Megasamples Second 32 768 points 12 bit DAC Money back Function Generator guarantee Ramps Triangles Exponentials amp more to 2 MHz ai Pulse Generator Telulex Inc model SG 100 Digital waveforms with adjustable duty cycle Starting at DC to 20 MHz linear Int Ext AM SSB InvExt FM PM Ramps Triangles and log sweeps Dualtone Gen BPSK Burst Pulse Generator Arbitrary Waveforms 2455 Old Middlefield Way S Tel 415 938 0240 http www Telulex com Mountain View CA 94043 Fax 415 938 0241 Email sales Telulex com CIRCLE 144 ON FREE INFORMATION CARD r 27 a BE AN ELECTRICIAN Home study Maintain and install electrical f systems wiring utilities
119. MH2 22m 800mhz batteries or 9V adapter FC 250C 119 95 220MHz benchtop 7 digit 10ppm accuracy 3 mV sensitivity 10 Vp p max input power by 9V adapter OA 149 95 1 2 Ghz bench type 8 10 ppm 35mV sensitivity 10Vp p max input power by 9V adapter FC 3700 329 95 1 3GHz bench type 8 digit 1 ppm accuracy 20mV sensitivity period 0 lus to 100ms Ideal for test amp repair of audio instrument CAP 15 349 95 3 digit 0 1pF 20mF 9 Ranges 0 1pF resolution Zero adjustment LCR 195 89 95 wH 200H mduct 0 1pF 200uF Capac 0 0102 20M 2 resistance LCR 814 189 95 0 1 wH 200H 0 lpF 20mF 0 1Q 20MQ Q Factor dissipation zero adjust LCR 131D 229 95 autorange 0 1WH 10kH 0 1 pF 10mF ImQ LOMO Q Factor serial parallel 120Hz 1kHz testing mode tate ee eee a ara eee ee DMM 113 24 95 Pocket Size DC ACV Q T FETEI TA SPR diode Continuity beeper j AAN ERRA KIAR ATA x 2 scone ta DMM 120 24 95 economy type DCV ACV Scope Meter Sound meter 169 95 e Watt Meter 129 DCA QUFE diode 92B 1 399 EMF Tester 69 95 High Voltgae Probe DMM 122 59 95 DC AC V A Q hFE diode 96B 1 699 Conductivity 169 95 59 95 capacitance freq logic continuity 99B 1 999 Thermometer pH Meter 79 95 DMM 123 44 95 DMM capacitance 105B 2 499 69 95 89 95 Light Meter 80 90 DC
120. MONEY BACK GUARANTEE ALLSTAR ELECTRONICS HOURS 9 6 M F 10 3 Sat EST respective owners amp are used for Converters amp Descramblers Call 1 800 715 6789 30 Day Money Back Guarantee oe ow a Ge Nt me Ge a stlenminiit Y t dts Full of Stars sPanazonic ejerro d PionEee Zenith Scientific Atianta ALL MAJGR CREDIT CARDS ACCEPTED 139 Laser LightShow at Draw with a laser beam Animation text music amp more Includes galvos munors servo amp demo software disk analog and digital computer interface Use an inexpen sive pen pointer or high power gas laser Ge g gt Motors 39 i Includes 2 Stepper motors 3 DC motors computer interface training manual amp demo sofiware disk Expandable Up to 12 motors up to 3 amps per phase Now with 4 Axis Linear Interpolation Add for shipping Computer with parallel printer port amp cable assembly power supply amp laser are required FREE FLYER Vaa 510 582 6602 a 510 582 6603 S J V273 industrial Pky West Ridg 460 PO Box 5325 Hayward UA 94545 0125 CABLE TV CONVERTERS AND DESCRAMBLERS Computerized e Scientific Atlanta e Jerrold e Tocom e Zenith e Pioneer BEST PRICES FREE CATALOG 0 782 7214 it is nat the intent of Allstar Electronics to pitas any pay TV operasor aie implying theft of service be denied assistance
121. NGINE TEMPERATURE CONTROL PRO SCHEMATIC EDITOR HIERARCHICAL CIRCUITS VIRTUAL INSTRUMENTS ON SCREEN GRAPHS ANALOG COMPONENTS DIGITAL COMPONENTS DEVICE MODELS MONEY BACK GUARANTEE TECHNICAL SUPPORT Powerful Analyses DC OPERATING POINT AC FREQUENCY TRANSIENT FOURIER NOISE DISTORTION VES YES SPICE 3F5 32 BIT NATIVE 32 BIT EACH DEVICE YES YES YES YES OVER 100 OVER 200 OVER 4 000 30 DAY FREE YES YES VES YES YES YES Electronics Workbench INTERACTIVE IMAGE TECHNOLOGIES LTD 908 Niagara Falls Boulevard 068 North Tonawanda New York 14120 2060 Telephone 416 977 5550 TRADEMARKS ARE PROPERTY OF THEIR RESPECTIVE HOLDERS OFFER IS IN U S DOLLARS AND VALID ONLY IN THE UNITED STATES AND CANADA ALL ORDERS SUBJECT TO 15 SHIPPING AND HANDLING CHARGE Fax 416 977 1818 Internet http www interactiv com CompuServe 71333 3435 BBS 416 977 3540 E mail ewb interactiv com CIRCLE 13 ON FREE INFORMATION CARD AUGUST 1997 Vol 14 No 8 6 Popular Electro A GERNSBACK PUBLICATION COVER STORY 33 The Hall Effect Electronic Compass If you do much traveling outside of your home state or even your neighborhood for that matter eventually you are going to get lost But with the easy to assemble electromagnetic deaan ee described in this article staying on the right course will be a cake walk David Williams CONSTRUCTION 48 A 100 kHz 30 MHz Active Antenna if you
122. O inches long the default English stan dard display will read 22 8 with the foot indicator lit or 22 8 feet Pressing the MODE button once switches the reading to 22 10 with the inch indicator also tit Although the display s precision is only o foot one inch or centimeter the ProMeasure s internal precision is higher and measurements can be stored with that higher precision Measurements are saved by pressing the L W or H key to indicate if you are mea suring the room s length width or height Formulas for area and volume are built into the ProMeasure Once a room s basic dimensions are entered a press of the VOLUME key automatically calculates the volume of the room To determine the area of the ceiling or floor you would measure the room s length and store it by pressing L measure and store into w the room s width and then press AREA To find out the area of the walls however you must be a bit tricky and input the length into L and the height into w Once you ve obtained the area and vol ume figures it s time to begin calculating how much of each material you ll need in the room Unfortunately the figures determined by the measurement comput er are not automatically transferred to the conversion calculator you must input them manually using the tightly spaced numeric keypad Particularly if you re using the same materials in several rooms you ll need to carry along a pad and pencil
123. OLOR HI y FINISH COLOR 2 5 TOUCT O1 C2 Ra Fig 3 Transformer Tl was wound on a i5 inch toroid core using color coded 3 x 32 trifilar wire Wind 20 inches of the trifilar wire on the toroid core as shown in A leav ing about l l inches of wire at each end of the winding After separating the leftover wire at each end of the winding strip twist and solder them as shown in B and mark the joints and remaining ends accordingly 374 inches A full size template of that printed circuit pattern is shown in Fig 2 Once you ve etched your board it s time to turn your atten tion to the transformer 11 a hand wound unit whose construction details are shown in Fig 3 Transformer Tl was wound on a 7 iINch toroid core using 3 x 32 tri filar wire three strands of 32 gauge wire that will be wound as a single unit The trifilar wire should be color coded If you cannot find color coded triflar wire don t despair you can always color code individ ual wires by painting what you have on hand Otherwise you can use an ohmmeter to perform conti nuity tests to determine which wire is which and then mark both ends of the wires accordingly In any event start by winding 20 inches of the trifllar wire on the toroid core as shown in Fig 3A leaving about an inch and a half at each end of the winding Separate the individual wires as illustrated and then strip twist and solder them as shown in Fig 3B e g one en
124. Popular i Complete Electronic Career Guide i 1000 s of satisfied customers Guarantee to pass or money back Send for FREE DETAILS or call VaEauesT ouR FREE caTALoS Wy poboistor es com 8007374 5764 Fax 415 455 9333 Email info mondo com 12800 800 7588 d 303 499 5405 Fax 303 494 4924 WPT Publications Internet http www siteleader com 0 4701 N E 47th Street I catalogdepot AMCSC home html r MI to Vancouver WA 92661 E mail amc sales siteleader com ja San Anselmo Ave 07 129 Name San Anselmo CA 94960 i Phone 415 455 9330 Ce E St lt 5 1 800 800 7588 _ J i L l Address I Lo aa ORIGINAL JVC OPTICAL PICK UP ASSEMBLY 5553 s0 i _ Optima 6s Bars Order Ne 46 2705 30 WATTS PENCIL SOLDERING IRON 4 30 Watts Power e Bakelite Construction 1 8 Tip Order N2 51 1055 HOT PRICES ON POPULAR SEMI S y eo ne SOLDER PASTE Semiconductors Security Product Celtular Accessories Educational Video Power Products Order Brand Min Price ain x roe He Remote Controls BU 208 TESLA 10 Cable assembly BU 208 0 TOSHIBA 1 seein 509 VCR Heads 2N 3055 TESLA 10 rder N 51 1920 Power Supplies 2N 3773 TESLA 5 n Soldering tools 2SD 1398 SANYO 10 Educational kits 28D 1650 SANYO 5 Frequency Counters C
125. RTS LIST FOR THE 100 kHz 30 MHz ACTIVE ANTENNA SEMICONDUCTORS Q1 MPF102 N channel JFET Q2 MPS3866 NPN silicon transistor D1 1N4007 1 amp 1000 PIV rectifier diode RESISTORS All resistors are watt 5 units unless otherwise noted R1 10 megohm R2 10 000 ohm R3 47 000 ohm R4 1000 ohm R5 100 ohm potentiometer R6 22 ohm R7 82 ohm R amp 147 ohm CAPACITOR C i 4 7 pF ceramic disc C2 C3 1 pF 50 WVDC electrolytic C4 0 047 F 50 WVDC Mylar C5 C6 2200 pF 25 WVDC electrolytic C7 0 1 yF 50 WVDC Mylar ADDITIONAL PARTS AND MATERIALS NEi Small neon lamp 100 voit breakdown CM1 type T1 Ferrite toroid core P N 768T 188 3E2A ACTIVE ANTENNA CABLE UP TO 500 FT UP TO 500 FT DC BLOCK 12 14VAC e WALL TRANSFORMER Fig 7 Connecting the 100 kHz 30 MHz Active Antenna to your receiver is a simple task As outlined here you simply connect the antenna assembly to the DC block and the DC block to your receiver Coaxial cable runs of up to 500 feet can be placed between the antenna preamp and the DC block or between the DC block and your receiver Don t forget to plug a 12 to 14 volt AC wall transformer into PL1 after all the preamp really could use the power J1 J3 Chassis mount F connector with flange PL1 2 1 or 2 5 mm connector Printed circuit materials 3 X 32 trifilar wire 12 14 volt AC 100 mA wall transforme
126. Remember that all signal splitters have losses since they are power dividers Potentiometer R5 can be advanced a little to make up any losses but most SW receivers have enough gain so that another 6 to 10 CB loss will not be troublesome A simple selector switch can also be used but that does not allow simul taneous use by more than one receiver This switch is best pur chased ready made Splitters and switches must be placed between the DC block and the receiver s I ah He Sok Mie tt in an BG Sey Ax agpang 4 a The DC block fits neatly into its metal enclosure On the sides Of the unit are the jacks J2 and J3 that are used to connect the unit between the preamp and the receiver input To the front of the unit is the power plug which is selected to mate with the connector of a wall mount transformer HANDS ON REPORT Continued from page 20 relieves you of having to peck your way around the mini keyboard of the Organizer by shifting this task to your full sized PC keyboard The program allows full editing capability before transmitting the additions or changes back to the Organizer A print option permits the selection of several pre defined formats so that the hard copy produced will match the page size of your favorite pocket organizer The program also provides the means for importing or exporting the data between your unit and another PIM Personal Information Manager Additionally either field
127. T amplifier The output signal is taken from the drain of the JFET The low pass filter consists of an RF choke L1 which is connected in series with the signal line while two capacitors C3 and C4 are shunted across the signal line Together those compo nents form a low pass filter that removes the RF and local oscillator signals leaving the difference sig nal which is the desired audio The output capacitor C5 is used to block the DC applied to the drain of the JFET The particular JFET used in that design an MPF102 will work to the VHF region The JFET easily avail able from a number of sources can be replaced by an NTE312 Another circuit shown in Fig 4B uses a MOSFET metal oxide semi conductor field effect transistor The device selected the 40673 is also easily available and can be replaced by an NTE222 In Fig 4B the incoming RF is applied to GI gate 1 while the local oscillator signal is applied to G2 The other parts of the circuit are similar to the ANTENNA Fig 3 A more refined direct conversion receiver block diagram is shown here This design while retaining the mixer local oscillator and audio low pass filter stages introduces an RF amplifier to the input of the circuit while adding an audio amplifier to the output Circuit of Fig 4A A passive direct conversion detector circuit is shown in Fig 4C That circuit uses a pair of diodes and a broadband RF transformer
128. a while all the parts did have including a bulb bought many years ago at Radio Shack migrated into my junk box still thought about the strobe light project periodically Then last week a friend of mine cleaned out his garage and gave me a commerciaily available strobe light that had seen better days It was at least 15 years old with broken wires and poor solder connections It had its own wood grain cabinet power supply and cord but no bulb As examined it thought This circuit looks very famil lar dug out the old article and found that the circuitry in the cabinet based strobe unit was about a 90 match with the circuit in the article scattered kajillions of electronic parts all over creation until finally found that bulb had bought so long ago still in its package Fortunately the article labeled the electrodes because RadioShack didn t label them at ail hooked everything up double checked everything crossed my fingers and turned it on It worked let out a whoop so loud you could have heard it clear down at the post office Thanks for printing the article and thanks to Marty Knight for writing it You never know how long readers will hang onto their electronics magazines for some circuits never go out of date M J McC KJ5BA Arlington TX Output Omission In the schematic diagram that accompanied my article Build a Four Mode Counter Popular Electronics Popular E
129. ad a low tube count it included some fairly sophisticated circuitry Now from Arthur L Manning Brunswick GA comes this tip on using an external antenna on the Star Roamer s broadcast band I have a Star Roamer radio and have been following your articles on it with interest If you use an outside antenna for long wave and shortwave reception you will find it does no good on the broadcast band band 2 That uses only a loopstick mounted on the rear of the set The addition of a very small coupling capacitor between terminals 11 and 1 of the bandswitch will allow loose coupling of the antenna into the loopstick and dramatically improve broadcast recep tion Fig 1 shows a portion of the orig inal schematic diagram in the manual with the added capacitor used a 4 5 pF capacitor because it was in my junkbox but any very small capacitor will do Do not use a large value capac itor as the loopstick resonance will be affected See you next month when we ll get back to our exploration of the Freed Eisemann NR 5 Neutrodyne three dialer If anyone has a unit we d like photos of it a Jose Returns H ose has sent in another big batch of quality circuits for us this month so he gets a kit and another MCL1010 chip along with the book awarded for single submissions Pel 117VAC Fig 1A The voltage across the load resistor is a reduced value of the input voltage Fig IB With one diode current flo
130. al users to keep their hard drive with their own applications and set ups Just turn the system off lift the handle and the hard drive pops right out Key lock included to avoid accidental or unauthorized removal Includes hard drive activity LED s Rack in cludes mounting hardware keylock front panel LED convenient pull out handle Made from high impact ABS plastic Fits in 5 25 bay Features Ideal for Hard Drive Portability Solve Software Data Security Issues Carry Your Hard Drive Between Home and Office Each User Can Have His or Her Personal Hard Drive DESCRIPTION PRICE For IDE Hard Drive 14 95 PRICE Etch Tank System 37 95 CATNO SpecialHDRACK IDE Digital Panel Meters LCD amp LED 3 1 2 Digit LCD 3 1 2 Digit LED 4 1 2 Digit LCD Don t let the prices fool you These digital eee ao conga panel meters are not surplus so even If you 2 design theminto an ongoing manufactured a 200 OO a ee eeu e Single 9V DC Operation product you can be assured of continued P eiA AUN et tert availabllity These high quality digital panel meters are decimal point selectable with Pori Polarity Indication ation guaranteed zeroreading atzero voltsinput e High Input Impedance gt 100 Mohm Applications Inciude Specifications PM 128 PM 129 Specifications PM 328 e Voltmeter e Capacitance Maximum Input 199 9mV DC Maximum Input 199 99mV DC e Thermometer Meter Maximum Display 1999 coun
131. almPilot a Stylus input device about the size of a calculator Several lights went on in my head knew this device was basically an electronic PIM knew it could ex change data with leading PIM pack ages including some of those was already looking into The PalmPilot was portable even more so than the old OmniBook and was well within my price range The big question con cerned the stylus input system knew that early versions of several products in this category were all but unusable but had read positive reviews about Pilots handwriting recognition ability There was only one way to find out So took the plunge Vendor Information a gt E The prices shown below are s g gt gested retail prices ae Outlook 97 399 95 Microsoft Corp Oe Microsoft Way Redmond WA 98052 6399 Tel 208 882 8080 Web ditpsAvww microsoft com InfoSelect 3 0 149 95 lt Micro Logic FO Box 70 Hackensack NJ 07602 Tel 800 342 5930 201 342 6518 Web Attowww miciog com Ecco Pro 4 0 3139 NetManage Se rap oe Ye 10725 North De Anza Blvd Cuper tino CA 95014 Tel 206 885 4272 Web http www netmanage com PalmPilot 299 PalmPilot Pro 399 includes built in memory Upgrade memory upgrade alone 129 Snap on modem 129 U S Robotics 1565 Charleston Road Mountain View CA 94043 Tet gt 800 881 r256 Web hitp HW usr ae l e e a A GA t am extremely happ
132. an E E Associate Editor of Popular Mechanix magazine In the preface the author grandly claims that this book was the first ever volume devoted in its entirety to the mainte nance and repair of broadcast radio receivers He goes on to Say that while soiu0soa 9 se indog 661 Isn6ny Popular Electronics August 1997 o simple enough for the veriest ama teur the volume is complete and exhaustive enough to be useful to the radio serviceman Appearing just prior to the age of AC or socket power radio receivers 1928 Radio Trouble Shooting contains information only on battery sets and on plug in battery eliminators But while repair data on early AC sets is fairly common detailed repair information on battery sets is harder to come by And there is more of the latter between the covers of this excellent book than have ever seen in one place before The book is organized in a logical and intelligent manner Its eight chap ters deal in order with tools and in struments propagation conditions antenna troubles batteries and charg ers battery eliminators tube troubles and remedies internal disorders in radio receivers and reproducer trou bles and maintenance The book is also extremely well illustrated con taining 257 numbered figures and charts many of them charming line drawings Thanks very much Lindsay for making this valuable compendium of battery set lore available
133. aps are highlighted as a single link When selected an arrow cursor appears allowing you to access any part of the image map Other keys on the top of the remote include up and down scroll buttons and BACK and HOME buttons In the middle of the remote are keys labeled OPTIONS RECENT SEARCH FAVORITES and TV WEB Below the central section is a power but ton If nothing of interest is presented then you can hit the OPTIONS button and select go to on the screen Enter any location you want and the WebTV terminal will take you there Most of the pages you will encounter will present no problems to the WebTV terminal which is compatible with most Internet standards including Real Audio It s not compatible with every thing however But one of the strong points about the WebTV terminal is that if it s not compatible with a given technolo gy now it might be in the future WebTV Networks can download software up grades directly to your box One of the exciting technologies that WebTV has in store is VideoFlash a tech nique for sending video over the Web Sure video exists on the Web now mainly as grainy images in small win dows that take forever to download And streaming video such as RealVideo is available But VideoFlash promises to outdo what s out there now One of the interesting things that VideoFlash does is take advantage of the TV screen s inherently low resolution when compared to a c
134. ar Audio Accessories Microwave Accessories Telephone Accessories STR 30130 SANKEN 1 TA 7777N TOSHIBA 1 DA 20 UNIQUE REALTIME OSCILLOSCOPE BUILT IN FUNCTION GENERATOR 2 CH DUAL TRACE 1 MHZ FUNCTION GENERATOR Features Wider than specified frequency response output terminal available Variable trigger hold off High output waveform frequency up to 1MHz Specifications Vertical deftection Horizontal deflection Time Base A 0 28 to 0 2S div in 19 calibrated steps 1 2 5 sequence Uncalibrated continuous control between steps of at feast 2 5 The most popular VCR ALIGNMENT TOOL KIT VCR Head pulley e Retaining ringremover e Spring hook Micro screwdriver Hex key set e Fitted vinyl e Soft zippered Case e 7 Assorted head amp guide aligners Dimensions 91 2 W X 121 4 L 3 Reversible screwdrivers Small Fiat Fillips lt gt 24 99 Z Order N 50 888 Lye DIGITAL MULTIMETERS DALCO Overload protect 1000V DC or peak AC on all other ranges Input impedance 10MQ on all ranges Base accuracy range 0 5 tot 1 0 Resistance 2002 2K 20K 200K 2M 20M Audible continu ity response lower than 502 DC Voltage 200mvV 2V 20V 200V 1000VAC Voltage 200Mvy 2V 20V 200V 700V Dim 6 75 H x 3 33 W x1 15 D lt i 19 8 Order N 50 850 in eet TUN O WASH 12 5 Oz aerosol MSc Fast drying electronics grade cleaner for tuners controis and PC bo
135. ard in North America on 6 150 kHz Over the years however other stronger stations began overpow ering its signals For this and other rea sons the shortwave outlet left the air a little more than a year ago in 1997 though the SW station returned on a new frequency 6 159 kHz where it again has been heard by U S and Canadian SWLs These are tests for new frequencies on the 49 meter band Tosun says We hope for better reception But new DON JENSEN SW equipment has been delayed due to financial problems Hopefully by the time this column sees print the station will be operating with a new U S made CCA Electronics 25 kilowatt SW transmitter and a folded half wave dipole transmitting antenna made by Kintronics Laboratories BRT s broadcasting center is in Lefkosa capital of the TRNC There it has its administrative and TV broad casting facilities plus eight radio pro duction and continuity studios Of its 400 employees Bayrak International as its shortwave service now is called has about 25 Bayrak has three main radio and TV transmitting sites on the island and several repeater locations Shortwave facilities are at the Yeni Yskele AM radio transmitting center in the eastern part of the Turkish Republic of Northern Cyprus Tosun says He lists the current schedule on SW as 0700 to 2200 UTC with English news at 1215 and 1730 UTC not very good times for reception in North America Howeve
136. arded watch The crystal XTAL1 was very carefully unsoldered and the crystal 1209 Hz 1336 Hz COLUMNS 1477 Hz ROWS Fig 4 The DTMF Frequency Counter ts amazingly easy to use Once properly con nected to the telephone to be tested apply power to the circuit and press any two row or column keys on the telephone keypad The readout should display depending on which keys were pressed a value consistent with the frequencies shown here can s leads were soldered to two pins of a cut down 14 pin header making it much easier to handle Some glue was then dabbed onto the assembly to hold the crystal in place the assembly was then set aside to dry while the rest of the counter Circuit was assembled onto the board Resistor R9 20 megohms is actually two series connected 10 COUNTER BOARD megohm watt 5 resistors When you finish wiring the board check your work for faults i e cold solder joints misoriented components mis connected components etc Once the counter board is complete and verified to be properly wired put it to the side and start on the display board Like the counter section the dis play portion of the circuit was assemble on a Radio Shack cata log 276 150 protoboard Begin by attaching two 24 pin IC sockets on the board end to end as shown in Fig 3 Note that there will be four unused pins on each 24 pin socket so be careful when wiring these sockets When completed th
137. ards CFE Free Designed for cleaning and Zz degreasing Consumer electronics 7 5 i Cleans in one step no rinsing e gt required Contains no ozone r ara depleting compounds HCFC free Not for use on energized oj equipment CFC and Order N 30 0100 FLYBACK im oT TRANSFORMERS gt 14 50 lt r e ne a Replaces a GOLDSTAR 154 074R Order Ne 63 850 20 MINIMUM ORDER CALL NOW FOR YOUR FREE CATALOG 1 800 325 2264 meita High deflection factor of 1myv dlv Wide dynamic range up to 30MHz without waveform distortion Algebraic sum of CH1 and CH2 Low drift with compensation circuit Superb trigger sensitivity Maximum sweep rate of video signals with Internal TV sync Separator Jittless trigger circuitry CH1 signal precision X Y phase difference measurement up to SOkHz Built in function generator with BNC output of 5022 and TTL Three kinds of waveform are available with SOQ output Flat Bandwidth DC coupled DC to 20MHz normal AC coupled 10Hz to 20MHz normal Deflection factor SmV div to 5V div in 10 calibrated steps of 1 2 5 sequence Rise time 17 5ns or less PLEASE MENTION P Bar Ne WHEN ORDERING CODE PE97 items are subject to availability Prices aro subject to chaange without any p 8 a b DALBANI i Skrrachi ROA SONY ANUA St BG amp E ers cbs ys Alig A omr GA ao GEER A coy SENN AS uN
138. art programming tools a NEW N Pentium 166 multimedia computer Powerful 166 MHz 4 system Visual Basic Windows 95 Pentium processor a and more based computer S7 ae Prepare for today s newest programming opportunities The Bureau of Labor Statistics forecasts that create the kinds of full featured powerful most powerful computer system available job opportunities for computer programmers programs today s employers and clients from any school will increase much faster than the average eran over the next 10 years with as many as e You start with BASIC building your Send for your FREE catalog today 400 000 new jobs opening up by 2005 confidence enough to create and modify See how NRI can give you the programming Now with NRI you can get the new several programs of your own skills the full featured computer system skills you need to build a top paying career e You move on to master C a sophisticated and the state of the art software you need to even a full or part time business of your language that s become me programming get started in this top paying field own in this high growth field tool of choice for a variety of applications If the coupon is missing write to us at Learn today s hottest languages e You re then ready to explore Visual Basic NRI Schools 4401 Connecticut Avenue With NRI s unique Discovery Learning oe oe Eee language NW Washington DC 20008 M
139. artment is rarely easy Finding the right number of rooms in the right location for the right price often takes many months And then when you think you ve found your dream pad a place that not only fits your requirements but also feels great to be in the broker showing you the place gets a phone call saying another agent has already accepted a deposit from someone else The word frustration takes on whole new mean ings when you are in this situation know what this process is like first hand as less than a year ago went through a four month grueling search that finally culminated in my ideal apartment But what if there was a way to learn more about an apartment before investing the time to go see it What if you could read more than just a ten word description in your local newspaper Thanks to a few innovative sites on the Web it s now possible to get in depth descriptions of prospective places to live and even see images of most of them online There is even a site that as we ll see in a moment that also lets you take a virtual 360 degree look at an apartment s interior right over the Web These visual features of the site come in especially handy if you re planning on relocating to anoth er state and can t afford to fly out to see just any place Rent Net With over one million and a half available rentals across the contigu ous 50 states and Canada displayed Rent Net using the latest in Web tech
140. ass ing the damaged hair cells and electronically converting sound into electrical signals that are sent Eats Jie Photomety Laser Took Cpa Window Help SAL IGIS P kga EOL a Ou SPHERE pine a Lambs sui i Findius _ Parameter Aperture Glass h c 0 0000 7 00 AIR Au c 0 0000 7 00 BK she MORE INFORMATION S Advanced Bionics Corporation 12740 San Fernando Road pass Sylmar CA 91342 Tel 800 678 2575 818 362 7588 ES Fax 818 362 5069 a Web hip Avww cochlearimplant com 4 Loh Se g a ee _M Yves Maigret gee Espace Vision 16 Boulevard Joliot Curie Nantes France 44200 Tel 33 40 75 03 07 Fax 33 40 eS 13 60 me a Newborn Hearisg Centre a i The Duchess of Kent Maternity Unit Hillington Hospital Uxbridge Middlesex i 5 England UBS 3NN Tel 011 44 895 279669 Fax 011 44 895 811687 Optis Ze La Farlede EES BP 275 Toulon Cedex 9 FRANCE 683078 Ee Tel 33 94 08 66 90 Fax 33 94 08 66 94 5 x i directly to the auditory nerve While they do not restore normal hearing the implants can benefit most pro foundly deaf people to varying degrees Candidates for implants are those unable to understand speech through the use of hearing aids and who have lost their hear ing after some speech and lan 9 Meas aa E n MEP bianna veien 2 T 4 ARAK SIY ls L la Darnel on gare 12000 Toi Tarem fed Ri Ra Serre isi i 4 GE i ae mr
141. aters antennas and more including standard and trunked systems Now they have entered the scanner market with two programmable handheld units the RELM models HS 100 and the HS 200 To be more accurate we should say that the company has re entered the scanner market You might not know that RELM was formerly known as Regency Electronics which had been a leading manufacturer of quality scan ners prior to the mid 1980s The HS 100 scanner has 100 mem ory channels set up in ten banks It covers a dozen two way action bands from 30 to 512 MHz including the VHF aeronautical band The more formida ble HS 200 covers 13 bands set up in ten banks including 800 MHZ Advanced features in the HS 200 include PL CTCSS and DPL DCS pro gramming capabilities Both scanners provide fast scan selective bank scan weather band scan priority scan with hierarchy direct channel access search search hold channel lockouts birdie lockouts and LCD display Both units come standard with AC adapter ear piece carrying strap and a metal belt clip They are powered by four AA pen light batteries easily accessible on the side of the unit RELM scanners are sold through the company s dealer network RELM Communications is located at 7505 Technology Drive West Melbourne FL 32904 Tel 407 984 1414 Battery Hints If you use standard alkaline batteries to power your handheld you find that eventually they run out of steam The
142. attery Operated 1 Labelled as DANGEROUS Product q 1 Experiment now before it is classified as a f firearm EGUN1 Plans 20 00 Must be at for purchase of henian Caution i Required ae We can deen aia build high voltage systems to your specs Call or fax us with your requirements S Sonic Blast Pistol Rids areas of unwanted pests Trains and conditions wild and domestic animals Great for bams attics cellars gardens f 39 50 PPP1K KitPlans D 5 1 those wiseguys SHKIK Easy to Assemble Kit 4 Life is Precious 1 PROTECT IT Stuns amp immobilizes attackers i t5 feet away Check your state ii laws for legality More knockdown g power than most handguns No permanent injury ID coded ECG1 Data g Creditabie to purch 10 00 asi ECG10 Charge Gun Ready to Use includes FREE Stun Gunt 49 50 24 Hour Phone 800 221 1705 Orders Oni Please 91U01 93 3 48 amp Ndog Z664 IsNbny un Run audio communications and other battery E QUALITY ALL S FAST ELECTRONICS s DISCOUNT C o R O R A T I PRICING 470 UF Mair aM VOLT Mair aM P IN CAPACITOR Nichicon LGQ2W471MHSC 1 375 diameter x 2 high 0 4 lead spacing 50 CAT EC 4745 NOTEBOOK een TER een CASE Great looking padded carrying case suit Ye able for most notebook computers or similar each 10 for 40 00 e
143. audio channels are coupled to the input terminals of IC2 and IC3 LM386N 1 by way of the resistor Capacitor pairs R3 C5 and R4 C6 for the respective left and right channels A band pass filter consisting of C3 R7 C1 and R5 for the left input and C4 R8 C2 and R6 for the right input passes both high and low fre quency audio depending on the vol ume of your CD player A low level input loses some of the high frequen cies and too much volume produces a distorted signal so adjust the volume The gain of the left channel output is determined by C9 C11 R9 and R11 and the gain of the right channel is determined by C10 C12 R10 and R12 The outputs of IC2 and IC3 are coupled to speakers or the inputs of a high impedance amplifier via capaci tors C11 and C12 respectively This circuit is designed primarily for use aS a preamplifier for the power amplifier presented earlier but if you want it as a low power amplifier you can connect an 8 ohm speaker to each of its outputs The circuit can be powered by a 9 to 12 volt adapter The 12 TO 17 5VDC C19 se c9 p C18 J1 1000 LEFT CHANNEL R3 C5 6 C13 INPUT 47K 220 8 220 C11 i 3 7 20 can 8 680pF 2 IC2 3 Py LM386N 1 R11 R1 i 47K LEFT r R9 R13 CHANNEL C1 R7 5K 50K OUTPUT 47 509 AS C15 j J2 RIGHT CHANNEL R4 C6 INPUT 4 7K 220 Ahh 4 RIGHT R10 R14 6 CHANNEL 5K 50K T OUTPUT
144. browsing Ideally items at JEFF HOLTZMAN arbitrary locations within the hierarchy could be linked although that was not an absolute requirement In my opinion Experience showed that things would become lost so searching would have to be supported across the full hierar chy or ideally any branch thereof OK So hierarchy information management was important But had other requirements of the PIM as well needed some basic scheduling functions nothing too sophisticated needed a task tracking prioritization and reminder scheme My dentist was literally tired of my missing appointments and had a few close calls with important business engage ments as well The problem is that when get deeply into some technical activity totally lose track of time and place Other Requirements Along with the primary requirements for a PIM that just summarized had subsidiary requirements as well objectives is probably a better word These were features would really like but could live without if there were other compelling features to compensate One was to eliminate the need to carry my daily planner address book with me all the time needed some electronic way of tracking my time billable and otherwise Another objective was some electronic way to easily capture infor mation at any time or place needed a method to centralize and simply record lots of personal information that my family would require in
145. cable TV equiDTe PE am DESCRAMBLERS S ERE THE DEALERS BUY a A IMPROVE YOUR IMAGE WITH BU abie Doscrambiers Wp A VIDEO STABILIZERS Con pox Catalog open Every Day A rni ABLE 0 Yon GRS ae CATALOG ED Caa S Darl any tape GUA R Seyi ys 2 Dye es REAA O SRR En rercavoougre 20t Copy any inchuded e Power Cons and RC Plugs oe wr 2 Yes Warranty sj CALL Now ye aaae Lie a Now you can tune in your favorite 30 DAY cable TV programming W ana SAVE St00 s o OLA EVEN S1000 S on premium f CABLE TV EQUIPMENT R 2 m MODERN ELECTRONICS 1 800 906 6664 e Tere a Z947 http www modernelectronics com n AA I ean Prem A es i p f 958 North Main St Mansfield TX 76063 CIRCLE 145 ON FREE INFORMATION CARD CIRCLE 149 ON FREE INFORMATION CARD Call for your FREE 348 page catalog TODAY 68 000 Products 130 Manufacturers All Orders Ship Same Day No Minimum Order 800 992 9943 817 483 6828 FAX 817 483 0931 www mouser com catalog mouser com Quality Microwave TV Systems WIRELESS CAE Ma pS ATV INTERNATIONAL BAND Amplifiers e Antennas Books Components Filters Systems Video Products RF Frequency 1990 2700 MHz Cable Ready VHF UHF Outputs SASE For FREE Catalog or Send 1 For Professionals Who Know The Difference Oscilloscopes Video Sync Test Generators Waveform Mon
146. can also be powered from the 12 volt supply of your car or boat Components RI C3 and Zener diode D1 provide voltage spike protection Integrated circuit IC3 a 78L05 5 volt 100 mA voltage regu lator is used to regulate the 9 volt output of the battery to 5 volts for IC2 Since the circuit draws over 30 mA of current JP1 is used to switch the battery source on and off oth erwise battery power will be lost Of course JP can be replaced by a switch if desired Assembly Instructions The Hall Effect Electronic Compass was built on a small printed circuit board measuring 4 by 2 g inches A full sized template of that printed cir cuit pattern is shown in Fig 2 The pattern can be lifted from the page and used to etch your own board If on the other hand you d prefer not to fabricate your own board a pre etched and drilled board can be purchased from the supplier given in the Parts List Once you obtain ail of the com ponents shown in the Parts List Fig 3 Once you ve obtained all the components needed for the project assemble the cir cuit guided by this parts placement diagram Be sure that IC2 1C3 the Zener diode the LEDs and other polarized parts including the battery connector are properly orient ed or polarized assemble the circuit using the parts placement diagram shown in Fig 3 Note that the printed circuit board contains seven short jumper wires Install them first using bits of solid ins
147. can directly drive the LEDs as long as the current is no more than 6 mA Resistor R2 an 820 ohm unit is used to limit current to the LEDs The author s circuit is powered from a single 9 volt transistor radio Ps No 1776 East 17th Street Clevetand OH 44714 216 781 9400 1 300 243 6445 MA an Education Just Training Independent study from CIE will give education at CIE matches or you the skills you need to win your own exceeds those gained through independence ina traditional commuter successful career institutes while At CIE we pride providing an educa ourselves in keeping tion schedule to pace with the latest match your commit developing technolo ments and lifestyle gies In turn this Our patented assures Our students learning program is that upon graduation specifically tailored they can mesh for independent seamlessly into a study and backed up variety of exciting and by a caring team of rewarding technology professional educa based careers tors who are at your Back in the 1930 s call whenever you we specialized in need their help teaching radio and At CIE we ll television sciences match our training Today its computer with your background technology program and career goals and ming robotics broad help you decide cast engineering which of the many information systems career courses that management and the we Offer suits you electronics behind it all best We offer an But some
148. case became disabled or worse And finally required a simple procedure to integrate all the information involved with these seem ingly random activities Then there were the hardware requirements Hardware had an old 386 based subnote book lying around a HP OmniBook 300 It runs Windows 3 1 has ROM based versions of Word and Excel and is quite portable It also has a nice key board which made it attractive for re mote work It turned out that the s31u01498 3 weindod 76614 Jsniny d Q3 Popular Electronics August 1997 d Ja You re never more than a phone line away from the information that s important to you Just snap on the PalmPilot Modem and press a button to connect with your desktop computer machine just didn t have the horsepow er to run any of the target applications even after a memory upgrade The big gest problems were lack of space and frequent program crashes which didn t happen on a desktop machine Very reluctantly gave up the idea of using it looked into purchasing a more modern sub notebook but the costs seemed way out of line looked into used machines and previous genera tion machines but was unable to find anything locally And was unwilling to purchase so personal an item via mail order even though there always seem to be lots of good deals available Then a friend showed me his new toy a US Robotics P
149. ce in Computer Science The B S E T programs now include Electronics Workbench Professional 5 0 An important part of being prepared to move up is holding the right college degree and the absolutely necessary part is knowing your field Grantham can help you both ways to learn more and to earn your degree in the process Write or phone for our free catalog Toll free 1 800 955 2527 or see mailing address below Accredited by the Accrediting Commission of the Distance Education and Training Council GRANTHAM College of Engineering Grantham College Road Slidell LA 70460 Editorial For Children of All Ages It appears to me that the older you are the more apt you are not to explore the computer s possibilities My opinion is based on watching children dive into exploring activities on the computer thereby investigating parts of programs that never even knew existed Why is this so Children are known to singe their finger tips while discovering hot and cold We adults cut down our exploration activities for fear of hurting ourselves Now computers cannot burn you but they sure can stomp on your ego Children don t respond to ego and peer Pressures as much as adults think they do With this amateur philosophy in the back of my mind undertook the learning of QuarkExpress a complex page maker program used in publishing Let me tell you that after a few jolts to my ego got defiant back to my chil
150. ch Speakon a AC operation adap tor included Built in recharging circuitry for ni cad batteries System includes 900 MHz transmitter wheless speaker pair AC adap tors and all cables necessary to hook up system Limited availability Net weight 9 Ibs Frequency response 20 18KHZ PO 319 030 a n ceeesseeeerenersnneereenneeess a s2U0198 3 seindog Z664 Isnbny Friday 9 00 am 5 00 for shipping estimate on Phone 937 222 0173 Fax 937 222 4644 w CIRCLE 146 ON FREE INFORMATION CARD Popular Electronics August 1997 oO Ja ALFA ELECTRONICS INC 1 800 526 2532 526 ALFA 15 Days M LCR METER TARA iti gr ee ae HIGH QUALITY TEST EQUIPMENT PROVIDER wens ISOC EE DMM 10 19 95 3 digit DC AC V O hFE diode signal output 3V 0 5 Vsq 50 duty DMM 17B 39 95 3 digit DC ACV contin DC ACA Q Capacitance hFE diode Freq DMM 20 74 95 AC DC V A Freq cont Capac Induct Q hFE diode duty cycle DMM 22 89 95 4000counts bar graph Freq AC DC V A Q Capacitance diode contin DMM 23T 99 95 4 digit high resol 10uV IOMA 10mQ hFE diode contin true rms DMM 89S 179 00 true rms AC DC V A Q bar graph freq capac dBm logic diode FC 1200 31729 95 1 25GH2z Handheld digits display Oppm accurary sensitivity Sm V 130 350MHz 30m V 440
151. com CIRCLE 150 ON FREE INFORMATION CARD GTRONICS In stock orders received by 5 00 p m YOUR TIME are Prices Effective June 2 through August 29 1997 To take advantage of these prices you must supply this special price code TENMA DMM with Temperature Function 3 digit DMM also doubles as an accurate temperature meter Ideal for appliance repair and many other applications Regular price 79 95 Order 72 4030 50 Watt 2 Meter Ham Amplifier Operates with less than one watt input achieves SOW out with 5W in Switchable 18dB GaAs FET preamp For the 144 148MHz amateur radio band only Regular price 159 00 Order 111 2100 t le price Speaker Repair Kits Why replace the entire woofer when only the rotten foam surround is in need of replacement Included in this kit are contents for repairing two speakers and consist of quality foam surrounds advanced formulated adhesive to work with many cone materials and repair instructions Order Description Kit 50 2726 6 kit 15 95 50 2731 8 kit 17 95 50 2736 10 kit 18 95 50 2741 12 kit 19 55 50 2746 15 kit 20 95 50 2751 2 dust caps 2 09 50 2756 3 dust caps 2 29 50 2761 4 dust caps 2 49 Same Day Shipping shipped the same day FREE 2 Catalog oes kee AAA e Bae aE EA sE h 2 Je D Ie s MCM ELECTRONICS 650 CONGRESS PAR 3 Aa CENTERVILLE OH 4 A
152. compass integrated Circuit see text U2 74HC154 CMOS 4 to 16 line decoder integrated circuit U3 78L05 5 volt 100 mA voltage regulator integrated circuit D1 15 volt Zener diode LED1 LED8 Light emitting diode RESISTORS All resistors are 4 watt 5 units R1 10 ohm R2 820 ohm R3 R6 100 000 ohm CAPACITORS C1 C2 0 1 yF 50 WVDC monolithic C3 100 wF 16 WVDC electrolytic ADDITIONAL PARTS AND MATERIALS B1 29 volt transistor radio battery connector JP1 2 pin jumper post and shorting block Printed circuit materials battery connector 28 pin IC socket insulated hook up wire hardware solder etc Note The following items are available from LNS Technologies 20993 Foothill Blvd Suite 307R Hayward CA 94541 1511 Tel 800 886 7150 a complete kit of parts for the Electronic Compass including etched and drilled printed circuit board 1490 sensor battery holder ICs and all other components listed above for 32 00 the 1490 digital compass sen sor IC1 for 15 00 the PC board only for 10 00 Please add 5 00 shipping handling for all orders California residents add local sales tax MC VISA orders accepted No C 0 D s puts of IC are fed to the BCD inputs of IC2 a 74HC154_ high speed CMOS 4 to 16 line decoder that s used to decode the output of the sensor The four pull up resis tors R3 R6 are needed since the sensor has open collector outputs The 74HC154
153. cs Web site start at http www gernsback com where the main navigation tool is a rotary switch Although the switch labels are perfectly readable on a VGA monitor they are illegible on a TV especially at normal viewing distances While WebTV Networks refuse to pro vide detaiis on the number of subscribers it has current industry estimates are that there are about 300 000 WebTV boxes in living rooms across the country TV set manufacturers including Mitsu bishi and Zenith are beginning to build Web access capabilities into their sets Web masters will have to decide whether they want to alter their page designs to be readable on a TV screen We encountered a few other instances where our TV s screen resolution just wasn t up to where we d like it most notably when viewing seating charts for sports stadiums or concert halls Granted many of these charts aren t really usable Gizmo is published by Gernsback Publications Inc 500 Bi County Blvd Farmingdale NY 11735 Senior Writers Christopher Scott and Teri Scaduto Copyright 1997 by Gernsback Publica tions Inc Gizmo is a registered trade mark All rights reserved on VGA monitors either because many institutions scan paper versions of their charts and post the file as a GIF image unaware that they re essentially unusable Most Web pages however look just fine on the TV The WebTV interface attempts to deliver some of the most popular In
154. ction 399 S H Visa MC Check OK 9 TTL output for control app s Add 99 for source code option 10 Visual Basic source code avail The top choice of corporations universities and scientists worldwidel Alli son Technolo gy C orp oration AMAZE ELECTRONICS CORPORATION 8343 Carvel Houston TX 77036 USA amaze hooked net www hooked net users amaze PH 713 777 0401 FAX 713 777 4746 BBS 713 777 4746 Phone 800 996 2008 Fax 408 374 1737 http www atcweb com l E m CIRCLE 137 ON FREE INFORMATION CARD Print log to disk or export data Single channel units from 169 Accepts standard scope probes Dual channel units from 349 Uses standard printer port Options Small and portable s Probe sets Works with laptops Automotive probes Same day shipping Battery packs f Made in U S A hm wh For industrial educational hobbyist auto and audio test amp measurement ON an Order yours today 800 980 9806 MC Visa Amex The PRIMER 8085 Based Microprocessor Training and Control System shows you how to program by example Examples amp exercises in the Self Instruction manual Paes take you from writing simple programs 5 to controlling motors Start out in d P th 275 x 275 Machine language then move on to Assembler amp then continue on with optional C Basic or Forth Compilers This trainer can be used stand alone via the keypad and dis
155. ctions sec 4000 instructions sec 2400 baud serial 1 0 50k baud serial 1 0 14 pin SIP module 24 pin DIP module Same I O instructions as BS1 plus touch tones frequency generation pulse counting s rial shift registers X 10 powerline control etc I O functions common to both mod ules have a higher resolution on the BS2 IC due to its faster clock speed PARALLAX 7 888 512 1024 Australla 61 39 720 5344 61 67 722 777 Austria 49 241 918 90 0 Belgium 32 4 377 5151 Bulgaria 4359 2 7277 50 Brazil 55 11 453 5588 55 11 801 0045 Canada 514 336 9426 Czech Republic 42 49 5813 252 Finland 358 31 266 1885 France 33 3 20 52 98 52 Germany 49 241 918 90 0 Greece 30 1 902 0115 Hungary 36 1363 6676 india 91 422 232 561 Ireland 44 1 977 683 665 Israel 972 3 498 543 Italy 39 0542 55400 Japan 81 3 3251 1779 Netherlands 31 16 450 4949 New Zealand 61 39 720 5344 61 67 722 777 Poland 48 34 648 88 Little Green Men from Mars Bjarne Bergheim Ken Ghristian William Jackson and Ben Strayer worked on the Flying Saucer Project at the University of California irvine Their project which used nvo BASIC Stamp H modules was a literal flying saucer Although not as dramatic as l follywood versions their saucer did indeed fly And fortunately it didnt come on independence Day Parallax now offers Basic Stamp Starter Kits All Starter Kits require use of an IBM PC running DOS
156. ctive reactance When an antenna s impedance is quot ed it is usually the resistive part that is meant This is the situation at reso nance reactances are zero Off reso nance however the impedance begins to See a reactive component Third and perhaps most important the dummy load provides the ability to conduct tests off the air where you won t cause televi sion interference TVI or broadcast interference BCI or interference to other users of the test frequency that you select Besides it is illegal and just plain rude to radiate when you don t have to One tune up use for dummy loads is to adjust antenna tuners You can connect the dummy load to the antenna output of the tuner and then adjust the controls for best VSWR at a number of frequencies By recording the knob set tings you can rough in the antenna tuner when repositioning Digital Frequency Counter At one time a digital frequency counter DFC was terribly expensive Even cheap models cost about the Same as new cars of that era They were heavy to carry and were power hogs can remember lugging one of those things up four flights of stairs to a rooftop penthouse where a bunch of commercial radio transmitters were located I ve come to appreciate the modern types Those early DFCs were really open only to professionals and that top elite of rich hams The rest of us used a receiver and crystal calibrator to mea sure fr
157. d countermeasures INTERNET TRACKING amp TRACING The Net is infected with spammers stalkers scammers infectors and other wrongdo ers who hide behind its ano nymity Learn how to trace them down in this comprehensive eye popping manual COMPUTER PHREAKING Describes in detail how com puters penetrate each other Mol and how VIRUSES TROJAN a HORSES WORMS etc are implemented Dozens of computer crime md abuse methods and countermeasures ln cludes disk filled with hacker text files and utilities and the legendary FLUSHOT protec tion system Internet advice password defeats glossary much more Manual PC Disk BEYOND VAN ECK s20 nein PHREAKING lt 9 EN Sea Eavesdropping on TV and computer video signals using an ordinary TV described in detail Includes security in dustry reports Range up to 1 KM Plans include both the Consumertronics and the original Top Secret Van Eck designs CREDITCARD aR SCAMS lt 9 ji ompletely describes ever known means of credit car fraud and scams counter measures Protect yourself Kast t a CONS amp SCAMS 29 Most comprehensive manual on C amp S available Details 100s their
158. d s only tapeless cleaning cassette It uses a patented brush process to safely and effectively clean without abrasion and reach where other cleaning cassettes cannot Absorbent fiber brushes housed in cassette shells automatically clean and maintain the inner components of a video system As dirt dust and oxides collect in a VCR s mechanism they accumulate above and below the tape contact area as well as in gaps and grooves of the video drum and video heads Failure to clean those areas can Cause picture and color loss as well as per manent tape damage Traditional flat The Video HyperBRUSH has a suggested retail price of 19 95 For more information contact Trackmate 5209 B Davis Blvd North Richland Hills TX 76180 Tel 800 486 5707 Fax 817 428 0567 CIRCLE 82 ON FREE al INFORMATION CARD AUTODYNE Continued from page 43 a 220 F DC blocking capacitor The input to the circuit is applied to pin 3 of IC1 through a 10k audio gain volume control Capacitor C2 connected from the DC power supply to ground is used to filter the source voltage applied to pin 6 of IC1 Capacitor C2 must be placed as close as possible to the body of IC1 In some designs there will be a 220 uF capacitor close to the IC and a 0 1 nF capacitor right at the IC body In doing some experi ments with the LM386 the use of C2 proved sufficient Also some circuits do not use C3 The gain of the circuit can be varied via a capacito
159. d The length of the pick up wire is pretty much up to the builder but a pick up Of from 16 to 24 inches is a good starting point for most applications In severe cases however if you live close to a transmitter the pickup wire can be shortened as needed but be warned that too short a pick up wire less than 12 inches may reduce weak signal perfor mance A longer pick up wire up to 4 feet can be used in weak signal areas Pick ups longer than 4 feet will not improve performance and may lead to excessive signal input resulting in spurious signal genera tion Therefore longer pick ups are not recommended If excessive interference and or noise is heard with RS at minimum and a shorter antenna try relocating the anten na to a quieter location TO PICK UP WIRE ANT1 Fig 4 Once you ve etched your board and prepared the transformer assemble the pre amp board guided by this parts placement diagram When installing the components be sure to connect the transformer as shown and also see that the polarized components are properly oriented Note that although NE appears to be mounted to the component side of the board it is actually soldered to the copper side 1 2 PVC CAP PICKUP WIRE n FASTENED 1 2 PVC TUBING TO TUBING END PICKUP WIRE 3 4 TO 1 2 REDUCER 3 4 PVC COUPLING WITH STOP PC BOARD ASSEMBLY 3 4 PVC TUBING m CENTER PIN TO TAP ON T1 SOLDER Lae JOINT x1 GROUN
160. d a few capac itors to turn the DBM s internal osciliator into a variable frequency LO A voltage tuned local oscillator using a varactor diode for tuning is shown in B for DC blocking Figure 7A shows how to use an external inductor and a couple of capacitors to provide a variable frequency LO A pair of DC block ing capacitors connect the NE602 to a Hartley oscillator i e tapped coil circuit The required oscillator feedback is provided by the tap on L2 that tap is at a point about 25 percent above the ground end The inductor L2 is resonated by capacitor C10 The inductor in Fig 7A should be an adjustable type if maximum flexibility is desired other wise use a toroidal inductor The capacitor can be either a single air variable capacitor or a parallel combination of an air variable a trimmer capacitor and perhaps one or more NPO ceramic or sil vered mica capacitors in order to obtain the desired capacitance and capacitance range A voltage tuned local oscillator circuit is shown in Fig 7B That circuit uses a varactor diode for tuning A varactor diode offers a capaci tance that is a function of the applied DC voltage V7 The par ticular varactor used depends on 12V C5 gt R6 7 02 1002 C8 01 2 1 mH Q1 c9 RF 40673 01 OUT Q2 C6 MPF102 22pF D R4 R5 C7 100K 100Q 1 Fig 8 A variable frequency oscillator VF O built around a 40673 dual gate MOSFET Q1 that can opera
161. d answer most ques tions you would ask a real estate agent For example you ll find out what important places are nearby such as shops and the like as well as specific rules regarding whether you can have pets smoke etc There are usually floor plans you can bring up too which will give you an idea of whether your sectional sofa will fit in the living room An outside view of the building is often available as are maps of the area But what about inside views Well as mentioned earlier some of the apartments listed at Rent Net allow you to download a sim ple plugin Total View and go through a virtual 360 degree tour of your prospective new place to live These tours tend to look best on Pentium machines with 16 megabytes or more of RAM but if you don t mind a little jerkiness of motion the tour should run on a 486 with at least 8 megabytes of RAM Once you re ready to get serious about a certain place you can either send e mail to the particular office Hicrosyji imie ea a a apaa e a a a di le e A ri Click here to see a photograph of The Georgian Ap artmenits k i F7 Click on the bedroom size to see floor plans of The Georgian Apartments tie Studio Two J wecennmasaiatres eamensaaresbnes Bee moe mange os OO Es DP Poa cae Urar e ee ge aa Ph TEAT n g pea m Maa h RA r n oe ae r a a T mT T ee e J e a a Raa n e m a a E T n e oa a m Fai Se nRa a a anon in ee ate fre eaten bea a
162. d b to light in turn Caus ing DISP4 to display a 1 On the second overflow pulse count 2000 pin 3 returns to its low state At the same time pin 4 goes high feeding that high through DI a 1N4148 diode to the input of U3 at pin 12 clamping the input high and thereby stopping the count At this 8 8VDC REG 5VDC Fig 2 Here is a simple power supply circuit consisting of a 12 volt 2 amp center tapped step down transformer T1 a pair of diodes D3 and D4 configured for full wave rectification a 5 volt 1 amp voltage regulator 1C7 and a few additional compo nents that can be used to power the DTMF Frequency Counter 2S O S EE o a M a s3lu01 93 3 1ENdod Z664 IsNbny Popular Electronics August 1997 Q o point all of the display digits have returned to zero When the counter has visibly gone through its count and all the digits return to zero you ll know for certain that the count has gone overrange The counter actually will count well above the audio range but would only display the last three digits The circuit was simplified to count only to 1999 Hz which covers all the frequencies used by tone phones The last three sections of _FND507 PIN NO FUNCTION 1 2 3 4 5 6 7 8 9 _ TO DiSP4 ONLY itor connected between pin 3 and pin 4 of IC3 The overflow output of IC3 at pin 14 is tied the clock input of IC6 b The BCD output of IC3 is fed
163. d of color 1 is connected to one end of color 2 and other end of color 2 is con nected to one end of color 3 Note that the connection between color 2 and color 3 forms the tap of the transformer whereas there is no connection NC to the color 1 color 2 junction Mark those con nections accordingly Connect the finished transformer to the printed circuit as shown in the parts placement diagram Fig 4 and then install the rest of the pre amp components in the positions indicated Because Q1 Q2 T1 as well as the wire used to wind the transformer and NE1 are critical to proper circuit operation no substitu tions or modifications to those com GND WIRE FOR J1 WIRE FOR J1 ponents are permissible Make sure TI is properly connected and that Q1 Q2 C1 and C3 are installed with the proper orientation Note Although NE1 appears to be mount ed to the component side of the board in Fig 4 in the authors proto type it is actually soldered to the copper side of the board Install a flange type F connector which is used to mount the board to its enclosure as well as connect the circuit to its power source to the board where indicated and then solder the antenna wire to the opposite end of the board The antenna pickup is little more than a length of 18 or 20 bare steel wire but any similar diameter copper wire should suffice The wire was soldered in line with and direct ly to the end of the boar
164. decibel sound effects The disc offered a chapter menu consisting of thumbnail stills that represented a dozen or so scenes That came in handy because we had an unusu ally large number or interruptions that afternoon including a real life thunder storm that offered some serious competi tion to the on screen weather action As promised and expected both video and audio were a quantum leap superior to that of videotape Next we watched The Wizard of Oz Judy Garland never sounded better Other than one slight glitch that resulted in a slight pause skip in play the picture was also of superior quality That glitch was created in the encoding process The addition of DVD even to a less than perfect home theater setup mea surably improved our viewing pleasure In fact it made us think seriously about doing some equipment upgrades A defi nite plus as far as the consumer electron ics industry is concerned The screen size certainly could have been larger and its resolution sharper and we wished that we had a Dolby Digital AC 3 amplifier While we weren t able to experience the full blown maelstrom of the digital Twister soundtrack the DVD sound delivered on our system still left us feel ing a bit battered and windswept And even though our television cannot deliver 500 lines of resolution the DVD images were crystal clear in comparison to stan dard broadcast fare or VHS tapes Continued on page 30 Meas
165. decrease the gain of the input signal Capacitor C3 is connected in the wiper Circuit of R5 as a bypass for AC signals With the gain control set so that all of the R5 is not bypassed Q2 provides a voltage gain of about 6 with an overall antenna to cable gain of 2 When impedances are factored in the circuit has an output gain of about 36 dB Potentiometer RS is adjusted for best results on a weak signal and it should be set for the lowest useable gain to allow for the best dynamic range Transformer Tl a toroidal wide band transformer with a 9 1 imped ance ratio determines the band width and signal handling capa bility of the preamp The 50 75 ohm antenna input of the receiver is transformed to 450 to 680 ohms as seen at the collector of Q2 Resistor R6 suppresses Q2 s tenden cy toward VHF parasitic oscilla tion DC bias for Q1 and Q2 is fed to the circuit through the tap on T1 Capacitor C2 AC grounds the cold end of T1 and bypasses the drain of QI The amplifier band width is about 10 MHz at 3 dB down but that s allowable as the antenna is more efficient at the higher fre quencies where less gain is need ed That s also desirable since SW stations on 12 and 15 MHz are sometimes very strong and can cause cross modulation Below MHz antenna pickup is the poorest and higher gain is needed The amplifier s low frequency point is around 80 kHz depending mainly on T1 That covers the lower limit of the
166. dhood and responded by poking and prodding my way through the complex program Guess what found out I m as tough as any teenager maybe as tough as a ten year old We all agree that many program manuals fail to explain things in a complete precise style or if they do the material is over complex or much too technical for the unskilled user discovered that kids whiz through the on screen tutorials and then dive into the menus with gusto The help button is pressed frequently and when a menu item or button function is mysterious or unkown the kids press it That was the approach used with great success It is true that the computer burned me a few times but never said Ouch So say to all you oldtimers from ages 20 through 95 turn on your computers and jump into a program You have nothing to fear but the mouse itself and the mouse does not bite Julian Martin Editor TECHNOLOGY UPDATE How to make your car invisible to radar and laser egally Rocky Mountain Radar introduces a device guaranteed to make your car electronically invisible to speed traps if you get a ticket while using the product the manufacturer will pay your fine by Phil Jones If your heart doesn t skip a beat when you drive past a speed trap even if you aren t speeding don t bother reading this I can t tell you how many W The Spirit H times that has hap will jam radar pened to me D
167. dio power than the one in the last letter take a look at the circuit in Fig 4 This stereo power amplifier is built around two LM383T 7 watt audio power amplifier ICs Although the circuit exhibits maximum performance and fidelity with a preamplifier the head C24 D1 1N4001 C21 89 2200 50V 1000 TREBLE R18 b 100K TREBLE 10K R20 150K LM383T Fig 4 This stereo power amplifier provides up to 7 watts per channel Good substitutes for the LM383T ICs are the NTE 232 devices 100K C22 2200 50V phone output from a CD player can be fed directly to jacks J1 and J2 It can then be coupled to the non inverting input of 1C1 and IC2 through resis tor capacitor pairs R11 C5 and R1 2 C6 respectively Balance between chan nels is accomplished with potentiome ter R8 An automatic gain system is formed using components C1 C4 and R6 for the left input and C2 C3 and R7 for the right input Dual potentiometers R5 R17 and R18 are used to uniformly vary the volume bass and treble con trol for each channel Again the tone controls are part of a negative feedback loop The outputs of IC1 and IC2 are cou pled to the speakers or headphone through capacitors C21 and C22 respectively Switch S1 is a power on off switch The fuse you need in series with this switch depends upon how much current you want to supply for the amplifier National Semi conductor recommends 3 5 to 4 5 amps per LM383 Since this
168. ds Create your own program to control your home automation system tuming on off any device plugged into an electrical outlet with responce to time date other X 10 transmissions or any other computer input stimuli 38 50 Telephone Scrambler Scrambles your volce before sending it over the telephone line Prevent eavesdropping from an extension or tap Connects between your telephone and wall jack No modifications are required to your telephone Full duplex operation 43 00 Add 4 FREE eeder uszcmis CATALOG Calier ID RS 232 Connects between a telephone wail jack and an AS 232 serial port ecodes the caller ID data sent over the phone line and sends it to your PC Mac In a pre formatted ASCII character string Create your own program to log the name number date and time of all Incoming calls ff Biock out unwanted callers to your BBS modem 34 50 IR Remote Control Receiver Learns and records the data patterns emitted by standard controls used by TVs VCRs Stereos etc Lets you control all your electronic projects with your TV remote Seven Individual 1 O pins can be assigned to any button on your remote and can be configured for either toggle or momentary action 32 00 Or large runs PCBs wave soldering cabinets and other metal parts silk screen printing plastic injection xformer coil winding etc Assembly wiring Very low prices Twin plant
169. e while industry support among consumer elec tronics and computer manufacturers is quite strong the motion picture industry is not as firmly committed to the format Columbia TriStar which is owned by consumer electronics giant and DVD pro ponent Sony Sony Music Video MGM Home Entertainment New Line Home Video and Warner Home Video are releasing movies on DVD Other major players including Universal Disney Paramount and 20th Century Fox are cautiously waiting to see how well DVD is accepted by the public before jumping on the bandwagon We re not sure what the future holds for DVD but we can tell you what it s like to use a DVD player right now Read on for a description of the Panasonic DVD A300U E DIGITAL VIDEO DECK Continued from page 25 When we switched from the VHS to the DVD version of The Wizard of Oz DVD s sharpness and clarity jumped out at us with the same startling intensity that Dorothy must have experienced as she stepped out of her dull sepia toned Kansas farmhouse into the brilliant colors of Oz Gizmo News Digital Imaginations As if you didn t have enough ways to spend your money out at a Major League ballpark the Eastman Kodak Company has come up with yet another although it s available only at Atlanta s new Turner Field so far This season fans will be able to pose for their own rookie cards get classic photo prints from the Atlanta Braves archives or even create p
170. e Connection j Y Now with NRI s new PC Options Plan you can keep up with late breaking advances in J State Zip__ i technology by upgrading your computer system at special student rates You ll get all the details i shortly before your computer is scheduled for shipment It s NRI s state of the art guarantee A Division of The McGraw Hill Companies H 3087 b m am me es ee ee ee ee a a Popular Electronics August 1997 NO Oo Palm sized electronic Organizers have been available for years but few pack as many useful features in such a small space as Texas Instruments PS 6800 Personal Organizer In a field dominated by two of Japan s biggest com panies Casio and Sharp an American manufacturer has finally produced a highly com petitive instrument Consider the following speci fications In a package measur ing only 3 by 5 inches and roughly a half inch thick TI has managed to squeeze in one of the largest liquid crystal displays 6 lines with 24 characters per line found in devices of this type A necessarily cramped 67 key entry pad occupies the remaining exposed sur face Internally a full 128K of storage memory provides space for thousands of personal reminders addresses and notes An identical Organizer with only 64K of memory is offered by Ti as the model PS 6700 The built in software includes a cal culator albeit only four function a clock with times shown in major c
171. e DVD A300U doesn t ook revolu tionary With its slide out disc tray and large jog shuttle dial it resembles a cross between a CD player and a VCR which in a way it is After all it plays both music and videos The disc tray is cen tered on the front panel with a large dis play just above it To the right can be found the jog shuttle dial topped by two SKIP buttons the OPEN CLOSE control and PLAY STOP and STILL PAUSE buttons To the left of the tray are the POWER button level controls for echo and optional head phones and microphone and jacks for phones and mic Several possible setup scenarios are described in the manual The most basic involves the DVD player and a mono TV the optimum arrangement includes an AC 3 amplifier and six speakers plus a subwoofer to take full advantage of the player s digital surround sound capabili ty Our setup fell somewhere on middle ground a large sceen TV with a Dolby Pro Logic receiver With the system hooked up we were ready to jump right in and watch a movie That s easy enough to do Pop in a disc select play from the main menu and you re in business If you want to take full advantage of DVD s many features how ever plan to spend a little time reading the manual and familiarizing yourself with the remote control In an unfortunate design choice the manual presents instructions in English French and Spanish on every page pre sumably so that the illus
172. e High Quality Fans feature Ball Bearings and Brushless DC Motors All of them are designed to meet UL CSA amp VDE Standards Design these fans into power supplies computers or other equipment requiring PRICE EACH additional air flows for heat removal AT NO l 10 25 Ve These fans are regular Circuit Specialists CSD4010 12 9 88 6 38 5 48 4 87 stock items they are not surplus CSD 6025 12 9 38 9 91 9 41 4 7 CSD 8025 12 8 88 5 85 5 19 ne i CSD9225 12 8 95 6 14 5 29 4 59 INDUSTRY BEST PRICING CSD 1225 12 11 45 8 96 7 82 6 85 RATED START INPUT STATIC DIMENSIONS VOLTAGE VOLTAGE CURRENT AIR FLOW PRESSURE SPEED NOISE LEVEL MM V V A CFM NCH H O RPM dB WEIGHT 9 40x40x10mm 12 7 0 06 5 1 0 19 5 500 26 20 60x60x25mmM 12 5 0 13 13 7 0 165 4 500 28 65 80x80x25mm 12 5 0 16 37 8 0 177 3 000 3 80 CSD 9225 12 92x92x25mmM 12 5 0 32 42 0 18 2 800 37 95 CSD 1225 12 120K1720x25er 0 35 62 0 180 2 500 42 135 e SOLDER gt SOLDER e SOLDER e SOLDER Westock high quality 60 40 Sn Pb 03 1 anad63 37 031 diameter This is prime JIS fa certified solder that we maintain as a SEF regular stock item It is not Left overs Rejects or Surplus and you can buy it from us ata fraction of the pricethat j you are used to Tired of Paying Inflated Prices for Solder PRICE EACH CAT NO DESCRIPTION l 10 25 RH60 1 l ib Spool 031 60 40 6 90 5 96 5 30 RH63 1 1 Ib Spool 031
173. e four FND 507 display modules are plugged into the two 24 pin IC sockets side by side Please note that the IC socket pins for DISP4 Count 1000 will be wired dif ferently so eave its wiring for last Modules DISP1 DISP3 are multi plexed That means that all of the like segments are connected together e g segment a of DISP connects to segment a of DISP2 and DISP3 and are connected to the card edge labeled a The same is true of all the b c d e POWER DISPLAY SUPPLY BOARD BOARD All three of the boards that make up the DTMF Frequency Counter were mounted tn a metal enclosure Located in the bottom of the enclosure is the power supply board the display was mounted to the front panel and the counter board was placed above the power supply using a card edge connector mounted to the rear panel of the enclosure PARTS FOR THE DTMF FREQUENCY COUNTER SEMICONDUCTORS IC1 555 oscillator timer integrated circuit 5 1C2 7T400 quad 2 input NAND gate s gt integrated circuit i C3455338 3 digit BCD counter micerated circu a 3 E4 TEn BCD to T segmen decoderdriver integrated circuit C5H0 14 staze counter with oscillator Integrated circuit 1C6 74L53593 dual binary counter integrated circuit DI D3 14148 general purpose small signal diodes s DISPI DISP4 FNDSOT seven s g ment commen anode LED display f RESISTORS AIl resisters are watt 5
174. e meter range PARTS LIST FOR THE METER RESISTANCE TESTER Fig 7 Al Re 5o 000 ohm a waltt 5 gt potentiometer sS1 SPST momentary push button Switch normally open Riadio Shack 275 1556 or equivalent Aligator clips RadioShack 270 249 of equivalent adjustable 1 5 E to 6 volts DC power source ete A bE tae aed Ret a Meter Under Test Many times bargain analog DC meters can be obtained at flea mar kets or hamfests These meters are great to use in your equipment provid ing that you place an external shunt resistance across the meter s termi nals In order to calculate this shunt resistor value you must know the TO NORMALLY CLOSED CIRCUIT Ss Fig 8 Here s a handy little tester which will alert you when Murphy s little grem lins intermittently open a connection O BARTSLISTFORTHE INTERMITTENTLY OPEN __ CIRCUIT TESTER Fig 8 Ci o 01 UF ceramic disc capacitor D1 D2 1N4002 diode ae SLED 1 Light emitting diode any color or type i aAi 4 0 ohm 4 watt 556 resistor A2 4700 ohm watt 5 resistor S1 SPST toggle switch Radio gt s Shack 275 612 or equivalent SCRl Silicon controlled rectifier 2N5060 RadioShack 276 1067 or a ee equivalent Bi 9 volt alkaline battery Alligator clips RadioShack 270 iir M9 or equivalent Btc internal resistance of the meter move ment Our next test circuit in
175. e of the best ways to learn a new language Expert Saft ware s new Speak German is just what you need if you want to learn German The disc transports users to a virtual German city where they can explore things meet people and learn German along the way You can hear perfect pronunciation see the correct spelling of any word record your voice and even compare it to a native speaker The program keeps track of multiple users remembering where each stu dent left off on the last visit For only 14 95 Speak German is a no risk en rollment in a beginning German lan guage class Destruction Derby 2 is now available from Psygnosis This is the sequel to the original automobile smash up derby game with realistic crashes and smash es Instead of displaying pre rendered crash routines accidents are now ren dered in real time everything but the crunching bumps America Wants to K There are also longer wider tracks with tunnels jumps alternate routes and banking corners Seven new tracks and improved special effects make this game even mcre exciting than the original Destruction Derby 2 is one way to smash out your frustra tions without damaging the family car and for only 50 New from Broderbund Software comes Koala Lumpur Journey to the Edge Ir this game you play Fly Koala s spirit guide through an animated comic book world You ll visit The Land of Lost Things Stream of Consciousness Eye in
176. each room and then try to determine how much of each material would be required for the job Even if we couldn t calculate gallons of paint per area of room at least we could give the guy at the paint store a real figure to work with Serendipity struck in the form of a package from Seiko Instruments Inc Inside we found a selection of electronic tools for home improvements including the ProTape 16 the ProLevel and the ProMeasure Home Contractor an electronic tape measure level and a tape less measuring tool that also performs material estimates The ProMeasure was exactly what we needed It measures distances elec tronically calculates area and volume and then computes the amount of materi als needed to paint panel carpet wallpa per heat or cool a room But we ended up putting all three tools to use before we had finished painting carpeting and then decorating the new upstairs Short reviews of the other two tools follow The ProMeasure Model HC1000 is a lightweight handheld device about the size of a remote control or a small flashlight In fact it looks a bit as if a soiuosoe g seindog Z664 isniny 25 Popular Electronics August 1997 N e flashlight had been somehow inserted into a remote Six inches long 24 inches wide the ProMeasure is about inch thick at its bottom At its top however the device measures just under two inch es in diameter The top is the electronic
177. ead of a low pass filter For example if you prefer an 800 Hz tone for CW then an 800 Hz bana pass filter would be used for the output filter stage From the output of the filter the signal is passed to an audio amplifier not shown A more sophisticated direct conversion receiver block diagram is shown in Fig 3 That radio design retains the mixer local oscillator and low pass audio filter but adds an audio output stage which can drive either a loudspeaker or ear phones as well as an RF amplifier stage The latter stage is used to amplify weak input signals and reject unwanted signals It also pre vents leakage of the local oscillator signal applied to the mixer from being radiated from the antenna to interfere with other receivers Note One of the dangers of some direct conversion designs is that the local oscillator signal can be erro neously coupled to the antenna causing illegal local interference to other receivers Simple Direct Conversion Mixers Any type of mixer circuit can be used for the front end of the direct conversion receiver and both pas sive and active designs have been developed For example consider the circuits shown in Fig 4 In Fig 4A a junction field effect transistor JFET is used as the autodyne mixer The RF signal is applied to the gate of the JFET while the LO signal is applied to the source Note that the source bias resistor is not bypassed to ground as it would be in a JFE
178. ed by a poor antenna In restricted use areas high rise apartment buildings or dense packed private homes the anten j f you re an SWL or AM radio DX na usualy a length of wire is strung around the room in a vain attempt to pluck signals from the air But an indoor antenna sur rounded by RFl infested AC wiring is unfortunately a very poor substi tute for a well constructed long wire antenna Adding to the prob lem are light dimmers computers fluorescent lighting TV sets and video equipment all of which can be real noisemakers In addition many newer electrical and elec tronic appliances and assorted gadgets are microprocessor controlled which generates lots of RFI Not to mention that with the frames of modern buildings com prised of various types of metals it s like living inside a shielded can with RFI generators going full blast If you ve encountered any of the drawbacks usually associated with the ham or SWLing hobby then just maybe this article will be of interest to you Presented here is a reasonable solution to most long wire problems the 100 kHz 30 MHz Active Antenna Circuit Operation A schematic diagram of the 100 kHz 30 MHz Active Antenna is shown in Fig 1 The incoming signal is picked up by the antenna wire and coupled via C1 to the gate of QI an MFP102 FET configured as a source follow er Capacitor C1 has a very high impedance to stray 60 Hz and 120
179. ed every two months so you know its fresh Comprehensive info on getting pirated software Includes examples counter measures and lots of tips 24 BY AN ORDER OF THE MAGNITUDE The most comprehen sive hard hitting hi tech survival book ever written Topics include lt electronic computer commo tte pom weaponry cryptography energy conceal ment revenge alarm disguise amp ID change Designs tactics amp strategies to survive an increasingly dangerous and brutal world Field expedient use of tech nology in various threat and conflict en vironments and scenarios 49 THE ULTIMATE SUCCESS MANUAL How to lie cheat steal influence and intimidate your way to success Under pi Overworked and erase messages and to convert them into mini VMBs Plus countermeasures protect yourself from hackers thieves 19 detail how Fax Machines are hacked and j i PHREAKING countermeasures Includes G3 28n CALLER ID amp ANI Fax protocols commo param n A eters compression algorithms Class 1 amp Details on how the Class 2 commands Spy Fax Switcher Fax Serv work and dozens of ef ers FODs FOCs and Makeup Terminating fective ways of defeat Codes And insights into designing Fax inter ing Caller ID ANI 69 5 Call Blocking 67 etc Also or read and modifying existing Faxes deictib s Caller ID O Pai info Stealth Paxes Eyes di ble describes Caller ID Orange
180. ed Accuracy 23 C 8 C RH lt 75 Temperature Ranges on a Operating 0 C to 40 C 32 F to 104 F Hish Storage 10 C to 50 C 14 F to 122 F g Power 9V Alkaline or Carbon Zinc Battery NEDA 180 Quality Low Battery indication BAT on Left of LCD Display Full Sized Dimensions 188mm long x 87mm wide x 33mm thick DMM Net Weight 400g DC Voltage DCV 0 0 19 Range Resolution Accuracy 200mMV 100UV any qty 2000mV ImV 20v TOMV 1 rdg 2dgts Resistance N 200V 100mV Range Resolution Accuracy 1000V TV 2002 100mQ Maximum Allowable input 1000V DC 20009 12 or Peak AC 20KQ2 10Q 1 2 1dg 2dgts OC Current DCA Z200KQ2 10022 Range Resolution Accuracy 2000K2 KQ 200A 100nNA 20MQ JOKQ 2 rdg 1lOdgts 2000uUA WA Maximum Open Circuit Voltage 2 8V 20MA 10A 1 2 rdg 2dgts 200MA TOOLA Diode Test 10A 10MA 2 rdg 2dgts Measures forward voltage drop of a Overload Protection mA Input 2A 250V semiconductor jJunctionin mV test cur fuse AC Voltage ACV rent of 1 5mA Max Range Resolution Accuracy OhFE Test a vail eRe OS Measures transistor hFE Frequency Range 45H2 450Hz Maximum Allowable input 750V rms Response Average Responding Cali brated in rms of a Sine Wave CAT NO DESCRIPTION PRICE 9300G Rugged High Quality DMM with Rubber Boot 19 00 Switchable Scope Probe Sets Selectable X1 Ref X10 These high quality scope probe sets are for oscillo Gee scopes up to 60MHz model HP 906
181. ed a college degree to qualify but you do need an FCC License No Need to Quit Your Job or Go To Schoo This proven course is easy fast and low cost GUARANTEED PASS You get your FCC License or money refunded Send for FREE facts now MAIL COUPON TODAY Or Call 1 800 932 4268 Ext 240 i COMMAND PRODUCTIONS FCC LICENSE TRAINING Dept 240 P O Box 2824 San Francisco CA 94126 Please rush FREE details immediately NAME ADDRESS ____ a ee CITY STATE _ ZIP ma ee sm cfte RELAYS LIGHTS MOTORS C TEMPERATURE PRESSURE LIGHT LEVELS HUMIDITY SWITCH POSITIONS THERMOSTATS LIQUID LEVELS I NEED A CUSTOM PCB TRY US DRA E CIRCLE 45 ON FREE INFORMATION CARD Don t rent Own Cable TV Descramblers We ll Beat Any Price Same Day Shipping e30 Day Money Back Guarantee eCredit Cards C O D eOne Year Warranty Have make and model number of equipment used in your area REPLACEMENTS FOR MOST SYSTEMS CALL TOLL FREE CD Electronics 1 800 684 9135 NO NEW JERSEY SALES Anyone implying theft of service will be denied assistance p E i a Lasers Tesia lons Anti Gravity Magnetics amp More Laser a Ray Gun 7 andheld 250KV Tesla Coil ra 10 14 of Explosive Bolts of Lightning battery operated Transmit Wireless Energy Produces an intense Anti Gravity Bburst of light capable of bumin
182. ed only for screening It refers babies with poten tial hearing problem for more exten sive traditional testing With a unit cost of only about 3600 the ARC means that all infants can now be screened Previously because of the time and expense involved only chil dren at risk because of rubella phys ical abnormalities or premature birth were tested very early in life So far some 6000 babies have been suc cessfully tested with the ARC Hearing of a newborn infant being tested with the Auditory Response Cradle s21u01428 3 seindog Z664 IsnBbny amp J Popular Electronics August 1997 amp a EA A 100 kHz 30 MHz ACTIVE ANTENNA Give your ham rig or DX station the pull it needs to catch the communications that you most want to hear WILLIAM SHEETS K2MQJ AND RUDOLF F GRAF KA2CWL fan living in or near a large city you ve no doubt been plagued by one or more of the common antenna maladies For example no outside antennas are allowed in your community or you live near an electric plant where high RF noise levels abound Perhaps you simply have no room in your yard for an outside antenna Other problems include theft and vandalism esthetics and unsightly appear ances restrictive covenants legal liability kids pets efc fear of lightning strikes and on and on ad nauseam And all ham radio fans know that even a good communi cations receiver is literally hobbl
183. eep beep Sensitive built in microphone Sensitive built in microphone f tone that increases from a low pitched Ideal for locating lost or stolen items Range up to 1 mile Range up to 1 2 mile growlioa oe pitched squeal as the sig f Range up to 1 mile Custom frequencies available Custom frequencies available J 4 Strength increases q ai TE MITTER KITS XST 500 Voice transmitter Range up to 1 mile Supersensitive mic Uses 9 volt battery Uses surface mount components XWB 1000 Voice transmitter Range up to GA Sus hij 1 2 mile Includes mic and battery on Circuit board Uses surface mount components XST500EZ XWB 1000EZ XFM 100C XFM 100 Voice transmitter Range up to 1 49 95 46 95 21 95 mile 9 v battery and leaded components 88 108 MHz FM TRANS 29 95 Worlds smallest FM radio As small as a hearing aid XSP 250 Super miniature telephone Weighs less than transmitter Range 1 4 mile Powered by 1 4 02 amp gt phone line Uses surface mount component Digital touch tuning a J XTR 100 Tracking transmitter Range up to ll c 1 mile Uses 9 volt battery Transmits a BEEP fF XSP250EZ XTR100C XTT 100C BEEP BEEP tone 34 95 29 95 19 95 XTT 100 Telephone transmitter Range up to 1 mile Uses 9 volt battery ideali for use with our 88 108MHz FM transmitters et BAe oe rN 3 THE ENFORC Oe a XPC 2 S XXE
184. ehr brand sold at Home Depot or the stuff Sears had on sale for 9 99 galion Although the ProMeasure offers no WOODFLOOR button we were able to take the carpet figure square yards and divide it by 9 to figure out square footage instead From there it was simple to determine how much more it would cost to put wood instead of carpet in the hall way and office The ProMeasure has its drawbacks Our biggest complaint is with the keys on the conversion calculator which were so mushy that we often had to press them several times before they would respond until we finally reverted to using a standard calculator and only using the conversion calculator s keypad to enter our final tallies We also would have preferred the conversion calculator to be linked electronically to the measurement computer so that all of those figures could be entered as the measurements were being made Measuring writing down adding up on a calculator and then finally entering the total on the Pro Measure was somewhat cumbersome And while a completely accurate mea surement is stored internally for use in computations the displayed measurement is rounded off That could Jead to trouble if you re measuring for something that can t be figured with the conversion Cal culator the exact length of a closet rod for instance It was however quite a bit easier to measure a room using the ProMeasure than with a standard tape measure Ii was
185. eiting magnetic stripe false front PASEL DEJ OL F MIND WF CONTROL TEMPEST Van Eck tapping spoofing inside job super cool vibration pase high voltage COLOR BOXES gt Fear increases over EM and ultrasonic mind others Case histories law countermeasures Dozens of PCB s de control technologies detailed security checklist labeled scribed many circuits f internal photos figures ATMs 39 Plus Call Forwardin contain up to 250 000 in cash especially implants Many more lies published than facts Secret ean g Phreak ama istory Glossary Diverters Extend PAGER BEEPER s29 agents are often used for reporting back MANUAL to covert organizations Learn shocking ers Loops REMOBS Bridging Heads amp Cans Optocom 3rd Party and many f truth about this bizarre phenomena 29 Describes in detail how Pagers ZA work different types and uses other non box methods more 29 da pained advantages over an uses with cellphones and tips and tricks How Pagers are hacked and countermeasures Includes plans for a Personal Pocket Paging System xmitter and receiver HACKING FAX MACHINES SPECIAL PROJECTS We design build modify repair consult on any device system process project elec tronic computer mechanical p optical eg hone auto security Radionic lab ener now rake in 2 Billion an nually Most are done with little fear of prosecution Detaile
186. ell us what you want Engineering staff Profes sional confidential Fax today 806 792 0207 Or write TESCO TECH Box 53743 Lubbock Texas 79453 USA ee PLANS KITS SCHEMATICS Oe TRANSISTOR Data Tables Given are the basic electronic parameters for the worlds popular tran sistors in one volume A must for servicemen hob byists and engineers Order Transistor Data Ta bles BP401 for only 9 95 price includes shipping from ELECTRONIC TECHNOLOGY TODAY INC PO Box 240 Massapequa Park NY 11762 0240 USA and Canda only US funds CRYSTAL Set Handbook Visit antiquity by building the radios your grandfather built Assem ble a Quaker Oats rig wind coils that work and make it look like the 1920 s Only 10 95 plus 4 00 for shipping and handling CLAGGK INC PO Box 4099 Farmingdale NY 11735 US funds only USA and Canada no foreign orders HEATH COMPANY is selling photocopies of most Heathkit manuals Only authorized Source for oem manuals Phone 616 925 5899 8 4 rr ee ELECTRONIC Project Kits www qkits com 1 888 GO 4 KITS 292 Queen St Kingston ON K7K 1B8 QUALITY KITS l GOTY RIS ee TRANSFER paper for printed circuits with laser or copier excellent quality 30 sheets 8 5 X10 with instructions 24 00 send check or money order to G SANTA MARIA 1602 A Washington Ave Suite 915 Miami Beach FL 331 39 ALL in one catalog 60 mouth watering pages CB HAM audio TV
187. elop at the edges of certain current carrying materials when they are placed ina mag re SE P K oe gt hb ae 3 So See spacers to a small section of Plexiglas Note When using the unit it is important to keep the sensor horizontal netic field The 1490 digital compass dey contains a miniature rotor on jewel bearings surrounded by four solid state Hall effect IC s The 1490 has four outputs that correspond to each of the four main compass directions North South East and West However because the range of adjacent outputs overlap each other by 45 degrees a total of eight different compass directions can be resolved with proper decoding The 1490 sensor is internally damped to give a smooth response to directional changes without over swing It has built in hysteresis to prevent unstable output signals The 1490 is designed to operate in a ver tically mounted position only If held off vertical some directional error will occur The 1490 operates from a wide range of supply voltages ranging from 5 to 20 volts DC The sensor can be damaged however from over voltage spikes or reverse power polarity Its power con sumption is approximately 30 mil liamps MA and the four outputs which are comprised of open col lector NPN transistors can sink up to 25 MA each As shown in Fig 1 the four out PARTS LIST FOR THE HALL EFFECT ELECTRONIC COMPASS SEMICONDUCTORS Ui 1490 digital
188. ent into reprint editions nine times It is packed with circuits theory antenna instatiation and tips on consumer radio receivers that were popular in the early 1920 s Antique radio buffs and those inquisitive about the early days of radio will find this booklet an exciting invaluable and excellent reference into the minds of early I 7 l h l A J l i l day radio listeners Sorry we I l l l I i i i l 4 A i Pal Ti m i PEE ae a cannot honor the original 25 cent cover price ELECTRONIC TECHNOLOGY TODAY INC P O BOX 240 Massapequa NY 11762 0240 Address E City State Zip I 4 Name l l l zF 00 RADIO HOOKUPS REVISED THE EIC O HOW TO USE OP AMPS Sj BP88 5 95 i The engineer s best friend is the op amp This basic building block is found in many Circuits analog and hu digital alike The op amp finds many i ar useful purposes such as A oscillators inverters isolators high and low fiiters notch and band pass filters noise generator power supplies audio MIDI and much more Prepared as a ie ani designer s guide some limited math 4 ier Summa i is used however engineers and es RR ini hobbyists alike find it a useful text for their design needs SHIPPING CHARGES IN USA AND CANADA 0 01 to 5 00 2 00 5 01 to 10 00 3 00 10 01 to 20 00 4 00 2
189. epeat this test Once you find the bad junction proper cleaning will cure the problem Caution Before removing or cleaning any battery post refer to your car man ual In some cars the computers don t like to have their power source interrupted ALLIGATOR CLIP Fig 3 This compact general purpose conti nuity tester is an indispensable tool for checking cables connectors and switches Its audiovisual output will keep you awake Make sure all power is removed from the circuit under test e4 PARTS LIST FOR THE CONTINUITY TESTER Fig 3 LED1 Light emitting diode any color or type A1 470 ohm 14 watt 5 resistor Bi 9 volt alkaline battery BZ1 Piezo buzzer RadioShack 273 060 or equivalent Meter probe RadioShack 278 704 or equivalent heavy duty alliga tor clip RadioShack 270 349 or equivalent etc x aes ae ele hak oh ee Gace eb 8 s ay PE ae oy Our next circuit in Fig 3 shows a simple continuity tester with an audible and visual output This is a great little tester to use in checking for low resis tance shorts and circuit continuity between cables and connectors It s s21u01 29 3 Jeindoy z66LIsNiny oo j Popular Electronics August 1997 oO ee also handy in checking out switches All power must be removed from any circuit used with this tester PL1 110VAC OUTLET SOCKET Fig 4 Use this handy little circuit to avoid smo
190. equency more or less Today the Situation is different While the best DFCs are still costly there are a num ber of ham grade instruments on the market The MFJ 346 DFC shown in Fig 3 features frequency measure ment to 600 MHz with 10 digit LCD pre cision and for only 189 95 A number of very similar models that are also very reasonably priced are available from about a half dozen sources and they ailow you to measure frequency accu rately enough for most ham uses These battery powered devices make the use of the DFC a game for all A Personal Note Every month at the end of my col umn provide my e mail and snail mail addresses in the hope that readers will contact me A number of readers take advantage of this and either write or e mail questions criticisms requests for information and so forth Not long ago got a letter from a reader who asked where he could get parts for his old Vibroplex bug a semi automatic telegraph key for you young un s recognized his name from my ham activities in northern Virginia about 35 years ago so called him on the telephone He was surprised but it was obvious that he didn t remember me asked him Do you still have that Hammarlund HQ 180 He was now really surprised how does a guy at Popular Electronics know about a receiver he had when he was a kid can be reached by snail mail at P O Box 1099 Falls Church VA 22041 or by e mail at ca
191. equivalent heavy duty alliga tor clip RadioShack 270 344 or equivalent etc Ep A Pk g Se coe Fl lars Be Let me share the solution to one auto battery problem that I ll bet every one of you has had at least once Your car was starting and running fine when you parked it You took care of busi ness and returned to your car minutes later but now it would not start All you could hear was a clicking noise no motor turn over Nine times out of ten the problem can be traced to the junction where the heavy battery cable connects to the battery post The connection can look just fine but a thin layer of oxidation can be hidden between the cable con nector and the battery post adding resistance to the circuit Since the car s starter takes several hundred amperes to bring the engine to life any added resistance keeps the starter from doing its job Examine the battery cables and post CHARLES D RAKES connections Since both battery termi nals must be checked start with either post terminal Take the first of our two troubleshooting circuits and connect the clip to one of the battery cable clamps and then press the probe in on the cen ter of that battery post Unless the con nection is really bad the indicator should be dark When the starter is en gaged the lamp should glow if you are on the bad connection If not go to the other battery cable clamp and its corre sponding battery post and r
192. ers better than laserdisc quality video Dolby Digital 5 1 channel surround sound and digital convenience on a five inch disc that looks just like a CD but has a much larger stor age capacity A single sided single layer DVD disc can store up to 4 7 gigabytes of information enough to hold a 135 minute movie A dual layer disc holds 8 giga bytes and a two sided dual layer disc can store a whopping 7 gigabytes A single DVD a can easily hold a full length motion picture with plenty of room to spare Even epic films like Lawrence of Arabia or Gone With the Wind can be viewed without having to flip over the disc which is considered a major drawback with laserdiscs Disc manufacturers can include soundtracks in up to eight languages and subtitles in as many as 32 languages One of the most talked about applications is to include on a single disc multiple versions of the same film with different ratings perhaps or your choice of endings In fact thanks to MPEG 2 video compression and the discs unique double layer design there s enough room on a dual layer DVD disc for as many as four films DVD also offers Dolby Digital sound capability formerly known as AC 3 Dolby Digital sound provides the sense of continuously moving sound through six discrete channels full bandwidth 3 Hz to 20 000 Hz for the front left center and right and the left and right surround channels plus a dedicated low frequency 3 Hz to 120 Hz
193. erse biased When current does flow it cre ates a voltage drop across the load current through the resistor is also close to zero producing only negligible volt JOHN J YACONO LAB TESTING COORDINATOR WINDOWS MAGAZINE IEEE age as shown by the waveform diagram in Fig 1B This diode in the circuit forms what is called a half wave rectifier and the resulting current is called pul sating direct current Now we have lower voltage with current flowing in only one direction although this current is intermittent What we need is a circuit that fills in the gaps So current continues to flow through the resistor when the diode is cut off Perhaps we could use another diode receiving bias current that is out of step with the one we have already Figure 1C is exactly that Here we are taking advantage of a center tapped transformer Relative to the center tap the polarity of the secondary voltage at point AA is always opposite to that at point BB except for those brief moments when the voltage is zero So when diode D1 is reverse biased diode D2 is forward biased and steps in to provide current to the load Let s look at the operation of the cir cuit one step at a time When point AA goes positive with respect to the cen ter tap diode D1 conducts Conven tional current flows through D1 re turning to the center tap by way of the load Also when the voltage at AA is positive the voltage at BB is negative At t
194. essed stamped envelope to Lud Sibley at 44 East Main Street Fleming ton NJ 08822 1224 or 2 Download the file from the New Jersey Antique Radio Club Home Page Attp globalent nevVoldradio but cur rently being changed to hAtto www eht com oldradio Lud anticipates that additional sup plements will be released from time to time as new discoveries continue to surface Star Roamer Echoes Reader Ed Gold Ezec KY writes Thank you for the series on the Star Roamer spent a summer mowing grass and baling hay to save enough to buy a Star Roamer kit At the time was 12 years old Somehow the radio actu ally worked couldn t tell you how many hours spent listening to the world got away from shortwave listen ing for many years but last year was in RadioShack and found a DX394 This is a good receiver but lacks the personality of my old Star Roamer I d give a lot to find out what happened to it 25 or 30 years ago Thanks again for all the great memories ne camel ey wma GREASTO BOARD 2 O BIRA wO Si How one man can erect an antenna mast from 1928 Radio Trouble Shooting eag E ES m ae ra Ph fg Ea are m lan E f BRICKS i 4 a 3 iy e I was impressed by Ed s achieve ment He put together a working Star Roamer at age 12 That was no mean task From my own experience can testify that while the Star Roamer re ceiver was inexpensive and h
195. ethod you get hands on programming designed specifically for creating programs CALL 1 800 321 4634 Ext 2564 in a Windows 95 environment experience as you master today s most http www mhcec com popular languages and programming Best of all you master these important SADAN U t environments Step by step you learn to languages as you train with and keep the SEND TODAY FOR FREE CATALOG More equipment more advanced software tar MN l re Ld Schools onnecticut Aver_ue Washington and more real world programming igi Check one FREE catalog only i experience than any eA COMPUTER PROGRAMMING x gE C PC Applications Specialist other school 7 Internet Sy as ee i Training l Q Networking with Windows NT ae O Microcomputer Servicing l Desktop Publishing with PageMaker C Bookkeeping amp Accounting il C Multimedia Programming i J Mastering Microsoft Office i C Webmaster Series E GET YOUR DEGREE ONLINE l lt 1 e AAS Degree in Accounting lt a AAS Degree in Business Management i Pentium 166 processor e 33 600 baud fax modem j ees pennan ar E e 16 meg RAM and 256K cache memory Netscape Navigator Web browser e 1 6 gigabyte hard drive e BASIC interpreter B name Age i e Super VGA color monitor meg e Power C and Visual Basic compilers please print g video memory e Windows 95 i panies I 8X CD ROM drive and 16 bit sound card e Exclusive access to NRI s Onlin
196. extensions using standard tone or rotary phones FAX and answer machines Plug in with regular phone plugs Easy to install Do it yourself 298 limited time special Plus S amp H California add sales tax Discount Code X4PE MSRP 399 XILLION Co http www xillion com 15447 Proctor Av City of industry CA91745 Tel 818 336 1890 Fax 818 336 2061 Boost your microphones output up to line level Plug your mic into our AP 1 and drive your amp to full capacity Connect an AP 1 to a pair of amplified speakers plug your mic in and you have an instant PA system Requires 6 to 12v DC Size 1 75 X 1 AP 1 kit 9 95 Read the code from any INFRARED Device e Complete with Software for any 80386 or 80486 base machine operating on DOS 3 3 or higher Sampled data can be saved to disk for instant comparison amp analysis e Zoom in on and view any 8 millisecond portion TIR 1 KIT 89 95 i DECODER Sweet 16 tone decoder operates great over phone lines radios or scanners e 16 TTL Level Outputs e DTMF Decoder Decodes 16 different touch tones using the phone radios or scanners e One relay amp driver circuit on board e 9v battery powered Size 2 3 4 x 2 1 8 TT 16 KIT 34 95 MICRO MINIATURE WIRELESS MIKE So small you could hide this one on some real bugs It s the smallest we
197. former pro vides an 8 volt source that is filtered by C7 and C8 a pair of 470 uF 25 WVDC electrolytic capacitors The 8 volt output is provided because some tone phones may require a lit tle more than 5 volts DC to operate In the other path the transformer output is clamped at 5 volts by the action of IC7 a 7805 5 volt 1 amp voltage regulator Construction The author s prototype was builf in two sections one section containing the four display modules DISP1 DISP4 and the other containing the remainder of the circuitry the counter section The counter was assembled on a RadioShack catalog 276 154A card edge protoboard which has copper traces and solder pads for the ICs When assembling your unit be sure to use sockets for all of the ICs Start by attaching sockets for D pae t up lle Le q in uu I b k m p B a af tm E in Lo By A lt i My ep DP NOT USED C D E the ICs to the board Install the sup port components as needed while using point to point wiring to make all of the interconnections between the ICs and the support compo nents Carefully check wiring When wiring up the counter board be sure to keep the input leads to the LM555 IC short and away from wires carrying 60 cycle AC otherwise you could pick up 60 Hz hum Be sure the 8 volt DC to RI at the LM555 input is well filtered for the same reason Remember that the crystal in the author s prototype unit was salvaged from a disc
198. foundly deaf for up fo 75 years The experiments have been very successful and now surgeons in many cities are perform ing the implants The CLARION sys tem is the first cochlear implant sys tem that was cleared by the U S Food and Drug Administration FDA in a decade and it is the only FDA approved cochlear implant manu factured in the United States E TRANSFER PAPER USE WTH REGULAR HOUSEHOLD ROH 30 sheets for 24 00 8 1 2 x 11 zr Send check or money or SPARE er to Ly Ta i 4 1348 Washington av NB 189 Miami Beaciy Florida FL 33139 MAKE CIRCUITS EASY FROM YOUR LASER OR PHOTOCOPY MACHINE ACTIVE ANTENNA Continued from page 53 hiding the antenna you may want to make several dummy units out of PVC pipe and arrange them around a bush tree terrace etc so they look like plant stakes The cables can be 50 or 75 ohms any type and are not critical but it is best to use a good grade of cable if runs longer than 100 feet are planned Miniature coax such as RG174 U can be used to keep things inconspicuous but remem ber to use suitable connectors and avoid mechanical strain Use coax suitable for direct burial Ask for the kind with a non contaminating jacket Black or dark brown cable jackets are easiest to obtain and camouflage well If an underground run is necessary and rodents are plentiful in your location you may want to think about running the cable through some i inc
199. g holes LAGUN2 Plans it Kit Plane Visible Beam lasers T LASIKM 1 mw low cost Kit LGUSK 2 3mw Kit mam GRA1K Power Supply KivPlans a ath GRA10 Assbid Kit Plans A raat pe J Star Wars technology weapons potential OG7K cies 50 5 10ma H Plasma Globe 1 Spectacular color Pulsates to mo i Mf sounds 8 9 with intensity and sound 1 controls PLASMA Ready to Use 79 50 A Cybernetic Ear Enhances normal iif Adjustable volume control Line Grabber A Infinity Transmit ji i e 3 Use tone phone anywhere i CYBEREAR 19 95 Access ongoing calls longwinded kids Control up to 8 appliances in your home 4 Re direct Costly toll calls from FY phones F TELCONS Pians credit to purch 1 TELCONSK Plans Kit VWPM7K_KitPians 39 50 TELCON30_Ready to Use hearing 3 4 times fits easily into either 13M Telephone Xmitter 4 Tune able 80 130 Mhz Undetectable 4 Only transmits when phone is used IP Pla ay i z Telephone Taping System 4 Tapes Phone Conversation Extends 4 Tape X4 Check se ae Laws before or aao 4 Tunable Output Uses FM Radio 4 Excellent Signal Beacon HOD1K Kit Plans stener 4 Aim at window and listen to sounds from 7 reflected light eae Not for p J use LWB3 Pian 10 00 1 LWB3K KitPlans i 20 00 Price on Reg m Many other experiments shown in detail Award winning science project
200. gles metal reinforced tool case with heavy duty ra Gare Driver handle and locks A removable pallet han SW 3 Solder Wick dies most of the tools listed with more room for tools and parts in the lower half Model XP 581 4 Fully Regulated DC Power Supplies in One Unit XK 550 Assembied and Tested 169 XK 550K Kit 139 Tools and meter shown optional MX 9300 Four Functions in One One instrument with four test and measuring systems 1 3GHz Frequency Counter 2MHz Sweep Function Generator GF 8026 w Frequency Linear and Log Sweep Digital Multimeter Digital Triple Power Supply g 4 OC voitages ai eo me on 1A 12V 1A 02Hz to 2MHz 0 30V 3A 15V 1A 5V 2A able 2 e Counter Range yo ina 1Hz to 10MHz eg 2 ee 479 4 Digit Display 225 Auto Ranging Hand Held Digital Multimeter Fluke Multimeters DMM w Bar Graph Model M 1700 70 Series 80 Series Model 70 69 95 Model 83 235 00 Model EDM 1 63 Mode 73ll 97 50 Model 85 269 00 Modei 75Il 135 00 Mode 87 289 00 Model 77il 154 95 Model 79ll 175 00 B amp K Precision Multimeters Model 391 159 00 Model 388A 99 00 sAd or ae ee ee arr Model 390 139 00 Model 2707 79 00 ERETTI Model 389 109 00 Model 28604 85 00 ease
201. gt Av LAPN64 15mw equy 2000 I LAPNE 50mw eq V 4000 HEP1 Pians Solid state Tesla Coil E Generate fiery electrical fields TCLS Plans pnosis Book amp Plans Parabolic Mic can hear a distant whisper BUG Nature 4 149 50 I Optional Wireless Retrofit transmits 1 captured sounds to an FM radio Raia Kit for aes OF tion 10 00 fEireBall Gun GE OE Shoots flaming ball two shot capacity Great for special effects and 1 remote fire starting CAUTION REQUIRED FIREBALL Plans dangerous product si 00 See In Total WUC High gy kai Night Vision illuminator S010 Read to Use m High Quality Laser Pointer 84 50 11000 Potato Cannon W Not a Toy Uses electronic or piez k j ition CAUTION REQUIRED 39 95 other 939 50 J STUN GUNS sold separately STUN100 100 000 Volts s000 34 50 pe TUN200 200 000 Volts ojan VISIT US ON THE WEB http www amazing1 com a CATALOG FREE with Order or send 1 P amp H 1 ATTENTION A pingid amp Resear Anti Gravity Rail amp Coil Levitation Research Exploding Water Propulsion Driverput Lattice Snapping EMP etc Loss less Energy Charger _ F with triggered spark switch Adjustable 500 to 3KV out oa F Charges up to 25KJ Programmable Output lt A 15 00 ge Guns Mass Warping Electric Gun prototype designed 1 Ballistic Velocities Handheld B
202. h PVC conduit to discourage rodents from chewing on the cable You will find that the antenna will perform as well as any prohibited or illegal long wire antenna you might try to install and probably better since it can be placed away from noisy AC wiring It will also improve the performance of some inexpen sive SW receivers as well The anten na was tested on several receivers including Hallicrafters S38D SX99 5X122 SX62 and an old National NC 98 as well as the receiver section of an Icom 726 all band ham trans age pet T d Ay Wace ae lege ORG ceiver In each case performance was excellent The antenna really did wonders for the old S38D and X99 40 years old And indoors the antenna was compared to a 5 foot telescoping whip A 10 to 30 dB improvement on signals from AM BC to some local 27 MHz CB signals was noted We think you will be pleasantly surprised at the performance that this antenna can provide Use With A Multiple Receiver Setup Many SWL hobbyists have more than one receiver and this antenna can drive several short wave receivers at the same time A signal splitter can be built using a few suitable jacks a metal case and a few resistors as shown in Fig 8 Commercially available signal splitters sold for TV and FM reception may be used but make sure that they will handle frequencies down to the lowest frequency that you want to receive Be warned some do not work below 30 Mkz
203. h is used in this circuit as the LO input The dif ferential inout amplifier is tuned by C1 and L1 a the coil Ll a has a low impedance tap to match the impedance of antennas typically 50 ohms The secondary of the input Coil L1 b is a low impedance winding that is applied to the differ ential inputs of IC1 The output signal is also differen tial so an audio output transformer is connected across IC1 s output terminals with one end connected to the 12 volt source as well Use an audio transformer that has a 10 kiiohm primary and either l or 2 kilohm secondary winding The audio output of the transformer must be routed to a high gain audio amplifier Another direct conversion receiver this one based on the NE602 is shown in Fig 6A The NE602 is a one chip approach to both RF and LO functions It uses a double balanced mixer Gilbert cell circuit in the front end and contains its own internal oscillator stage alll within an 8 pin DIP package The double balanced mixer provides a cleaner output than other mixers because only the sum and differ ence signals exist the LO and RF signals are suppressed in the out put The input circuit is tuned by a transformer comprised of coils Ll a and L1 b and variable capacitor C1 The transformer coils are wound on a toroidal core Coil L1 a consists of several turns 2 to 6 wound over L1 b The main tuning inductor is L1 b which must have an inductance that
204. h of inch pipe or conduit that holds the pickup antenna A cap is placed at the end of the 2 inch PVC pipe that holds the far end of the antenna wire in place The wire is folded over the pipe end and the cap forced over it Do not use a screw as this will result in exposed metal and possible water leakage Once that step is com pleted check out all wiring and the component placement Now turn your attention to the DC Block The DC block was hard wired into a small metal box as shown in Fig 6 A good source of such enclosures are old video game switches or junked TV assem blies You can also use a small metal project box Do not use a nonmetallic enclosures as RF shielding is necessary here Wire the Circuit together using Fig 1 and Fig 6 as a guide The DC Block can be mounted in any convenient spot as location is not critical If would be best to choose a spot more than 2 feet from AC wiring to mini mize the chance of noise pickup Checkout Procedure After all wiring has been checked out and found to be OK apply power to J1 solu0ijoe q seindog 2661 Isnbny on wok Popular Electronics August 1997 a NO J2 TO ANTENNA Fig 6 The DC block which serves as the preamp section s power supply was hard wired into a small die cast metal enclosure A good source of such enclosures are old video game switches or junked TV assemblies You can also use a small metal project box Do not use a nonmetall
205. he scan ner bands Kyler Abarnathy of Hawaii tracks endangered seals via the ARGOS satellite system He is licensed as WA2XEE on 401 65 MHz Aienco Communications Inc in Texas as WA2XEK tests the feasibili ty of a BETRS wireless local loop on 454 70 454 975 459 70 and 459 975 MHz California State University is licensed as WA2XDI on 401 7025 MHz to collect weather information from the GEOS satellite system The state of Alaska does the same as WA2XFE on 401 7355 Mhz Digital Radio Technology Inc oper ates as WA2XDO on 112 45 136 125 136 15 136 75 136 775 and 136 80 MHz This signal is broadcast through out the United States to develop datalink radio equipment for both air craft control and differential GPS navi gational landing systems Harris Corporation in Florida oper ates as KB2XEM to test and demon strate mobile data automatic vehicle location computer aided dispatch and digital voice on 811 00 816 00 and 856 00 861 00 MHz The same company also operates on 136 00 136 40 and 136 425 MHz to test a VHF digital link Oregon Emergency Management uses the callsign WA2XFO on 406 025 MHz to test and develop personal loca tor beacons Radian International based in Texas Operates a wind profiler radar on 915 00 MHz as WA2XEA This is for air pollution studies in Houston Continued on page 74 A Couple of Neat Things For Hams ingle Bells Jingle Bells No haven t gone whacky and I
206. heard with substantial ly better signals Before going into detail about this station let s first have a little history Turkish Republic of Northern Cyprus TRNC an independent nation but one recognized by only Turkey BRT Is Born The Turkish Republic of Northern Cyprus runs a semi official broadcast ing organization that is called Bayrak R and Television Corp It was founded in 1963 says Mustafa Tosun head of the Transmitting Department of BRT when Turkish Cypriots were deprived OSL card from Bayrak Radio and TV en Cyprus Cyprus is Asian and lies only wo score miles off the coast of Turkey Cyprus is also European the majority of its people are Greek And it is that split that has resulted in major problems for this island nation Cyprus a former British crown colony gained independence in 1960 Greek and Turkish Cypriots found they could live together under a single gov ernment However in 1974 Turkey in vaded and took over a substantial area of the island Nine years later Turkish Cypriots declared this territory the Credits Brian Alexander PA Erik Bueneman MO Jim Moats OH North American SW Association 45 Wildflower Road Levittown PA 19057 BAYRAK RADIO amp TV RPT of access to the existing Cyprus Broadcasting Corp It has local AM and FM radio and TV services plus an overseas SW operation The SW voice was small only 7 5 kilowatts of power but Bayrak R some times was he
207. his time diode D2 is reverse biased and no current flows through it Eventually the voltage at AA drops and goes negative with respect to the cen ter tap diode D1 stops conducting When the voltage at AA becomes neg ative the voltage at BB is positive Then diode D2 conducts current which flows through the load back to the center tap Note how the direction of current through the load remains the same regardless of which diode is con ducting at the time This diode transformer configura tion makes up a full wave center tap rectifier circuit although the resulting waveform is still termed pulsating DC Can you think of a way to use four diodes and a plain transformer to achieve the same result We will explore the answer to that next time Now let s get to the letters soiu0djoa q seindog 2664 Isniny w Popular Electronics August 1997 D gt 9 TO 12VvDC ______ _ __ ______ S1 ON OFF D1 1N4001 C6 m 047 LEFT CHANNEL INPUT 5K IC1 a LM386N 1 50 j R3 a C10 250K 47 VOLUME R2 R6 a R7 50K RS 100K 7 5K 5600 BASS m pp ewer a C14 C5 a C13 a2 f 4 7 aa R1 R8 L aaa _ 1K R23 22k 22002 I T R9 a E O B me R22 von E TREBLE 500K i BALANCE a MONO d C26 L cz l C28 680pF 47 J2 sd STERED 047 RIGHT l i CHANNEL Rig C18 C25 amp INPUT I sk 22 220 5 IC2 C15 LM386N 1 SOpF R3 b C
208. hone 1 614 759 3666 8 30 am to 5 00 pm EST Monday Friday B Fox 1 614 759 3749 24 hours a day 7 days a week e Ciub 0112738 47 Hardcover 036432X 29 95 Hardcover 0241906 34435 P Hardecver amp 73092X 19 95 Basic Electrorics Cours ing tation 1574875 19 95 0053553 50 00 0304122 17 95 McGraw iitl Circuit 3 ne ent MOUSTRIAL Into Great J laj Eees 0376115 36 95 Security Systems Puree k tit 0717753 19 95 ee 0331898 XX 89 50 Trosbieshaoting amp Repsirieg Solid State TVs 0157537 XX 44 95 Hardcover Counts as 2 TROUBLESHOOTING amp REPAIRING GORDUN MeCIME 155016X 34 95 i ELECTRON NIES SS 3A HANDBOOI f SONALI ROS Counts as 2 1577564 24 95 0305285 39 95 Hardcover 0359768 19 95 5869349 44 00 skaj to test almost everything electronic 0304068 17 95 0376581 39 50 athe RI BASIC MATHEMATICS FOR ELECTRICITY AND ELECTRONICS 0044392 12 95 Handbook af Electrical Eanstructian Tools and Materials Al ED 0699208 65 50 E purana S 4 1570519 17 95 Troubleshooting amp Repairing wes Sader d Bees 0053146 24 95 0765359 34 95 Hardcover 0317917 60 09 Treuileshoeday Maintaining amp Repairing Persenal Lemputers ORR uaeresrs we totoa fc A i E h rad fa amp
209. hor rifying seven deadly sins which are split between each side of the double sided disc The Mask on DVD disc features a com mentary voice over from the director Charles Russell as well as two addi tional scenes that were not included in the original theatrical release phone calls With the scene marked the rest of the family can finish watching the film and she can come back later and eas ily pick up where she left off as long as the disc hasn t been removed from the player The DVD A300U offers a few other convenience buttons Those include AUDIO SUBTITLE and ANGLE which allow you to change the audio soundtrack or subtitle language turn subtitles on or off or select a different viewing angle during play without going to the menu Of course those options must be avail able on the disc being watched Like all other DVD players the DVD A300U is backward compatible with audio CDs and video CDs The DVD con trols described above work similarly for those older formats In addition the PLAY MODE button can be used to program the playing order of up to 18 audio tracks Offering a microphone input and the abil ity to turn off the vocals on video discs the DVD player can also be used for karaoke sessions The first DVD disc we opened was Twister a film we d yet to see other than at manufacturers DVD demo sessions It s a good pick for the DVD format with lots of action and plenty of high
210. hotos that digi tally place them in action scenes The three different systems Braves Rookie Card Braves Memories and Braves Scrapbook will be available at all home games Braves Memories arguably the most interesting of the systems features real time video posing in which fans see themselves on a video screen interacting with players in the great moment that they choose such as the scene shown here after an Andruw Jones homer The fans can adjust their poses to best fit the chosen scene If you don t live in Atlanta or if you just hate the Braves don t despair Kodak is working to bring its Kodak Digital Science photo systems to other stadiums A h Kodak s chroma key technology was used to insert a fan into a home plate celebration picture with left to right Brave s first baseman Fred McGriff outfielder Andruw Jones and catcher Javy Lopez HDTV IS COMING Well OK not HDTV but DTV What happened to the H It s gone in the pur suit of profits Perhaps that s a bit too cynical But while few people were looking HDTV or high definition television became DTV or digital television The difference is that DTV can be high definition but it doesn t have to be Instead broadcasters can cram several standard definition sig nals into the space where one high defin ition signal would fit In the words of the FCC The Com mission will not
211. i order cust if orders exceeding 5 Ibs Foreign destination customers please send 340 E First St Dayton OH 45402 1257 5 00 U S funds for gatalog Quantity pricing available omers please Ca UNBELIEVABLE Z VALUE ROAN pa g ce wet r n wee 4 a z s Pl ca i T i n ali E i FS Peak Instrument Co proudly gt introduces The Woofer Tester Just ask any loudspeaker engineer and they will tell that the only way to design enclosures of the correct size 1 a and tuning is to measure the Thiele gt is P Small parameters for the actual drivers to be used The reason Manufacturers published specs can be off by as much as 50 But until Pe ODAY now measuring the parameters er MOREY BACK 5 GQUULRANTEE yourself required expensive test equipment and tedious calculations or super expensive measurement systems 1 200 to 20 000 The Woofer Tester changes all that Finally a cost effective yet extremely accurate way to derive Thiele Small parameters in only minutes The Woofer Tester is a combination hardware and software system that will run on any IBM compatible computer that has EGA or better raphics capability and an RS232 serial port The Woofer Tester will ganone the ollowing parameters Raw driver data Fs Qms Qes Qrs Vas BL SPL 1W 1m Mmd Cm and Rm Sealed box data Fsb and system Q Vented box data Fsb
212. ic enclosures as RF shielding is necessary here Wire the circuit together using Fig 1 and this illustration as a guide For the checkout procedure use a positive 13 volt DC source with the negative lead connected to the preamp s ground plane Set R5 to the default position as follows If you live in a city set R5 at mini mum gain fully CCW Also use that setting for the less expensive solid state receivers that may be sus ceptible to overload and spurious responses as this antenna can deliver a lot of signal Amplifier lin earity will also be best at lower gain settings If you live in the country far away from strong AM signals set R5 about halfway to two thirds CW from minimum Next check for the following volt Oi BP HRs g CAUTION Use care when connecting this or any other antenna to certain older tube type SW receivers that may use a hot chas sis AC DC types as a shock hazard S38D used as one of our test sets is this type Check your receiver docu mentation to determine what it is If in doubt elther consult a qualified techni cian or do not use this receiver with this amenna Do not install this or any antenna or associated lead ins near over or under any power lines or where there is a possibility of accidental con tact with power lines Performance will Suffer and you could be electrocuted Note that this antenna is for receiv ing only Active antennas such as this are not designed for tra
213. iently arranged alphabetically No need to call up the entire record if all you want to see is the phone num ber associated with your selection Of even greater value is the Find button that lets you search the entire data base for the occurrence of any keyword Thus if you have stored the names of service people whom you need to call upon their records can be displayed by entering Plumber Caterer Computer Repair etc This feature not commonly found on more expensive organizers raises this unit above the level of being just another electronic Rolodex A Bookmark function lets you mark any record as the one you may want to quickly return to the next time you turn on the Organizer While of limited value this feature epitomizes the inno vations that TI s engineers chose to program into the PS 6800 s read only memory Typical of these pocket won ders is the ability to store both daily and yearly reminders that trigger an alarm alerting you to the upcoming event You can even set the advance notice time you want to be notified of any appointment or task A variety of choices let you scan by week month or year for birthdays anniversaries or other special occa sions you ve opted to enter The built in calendar good to the year 2059 aids in planning engagements Use your PC Tl offers the PS 6155 PC Con nectivity Kit No user of the PS 6800 Organizer would want to be without this compact docking
214. in your four LED displays as shown in Fig 3 _ PARTS LIST FOR THE POWER Su 1778087 8 volt ime p yorage _ Tegulator PART cirat _ rectifier e capacitor e EET CRATE 2 WoC steric oe gapaditor te oe T1120 6 voll i Tap centers PP per a step down power transformer Proteboard line cord with plug w wire solder hardware ete inch piece of sinch clear plastic SS as was used to cover the display power supply to the circuit Connect I fourconductor modular telephone line cord between the phone to be tested and SOI on the DTMF Frequency Counter Apply power to The 4 conductor telephone Jack was mount ed in a cutout in the front panel along with the display and the power switch The author opted for an internal power supply the one shown in Fig 2 Most of the power supply Circuitry was assembled on a small piece of perfooard with only the power transformer mounted off board to the chassis If you build the power supply the 7805 voltage regulator will require a heatsink Also use an extra 10 uF tantalum capacitor on the counter circuit board VCC bus if there is any instability Once all three boards are completely assembled and have been checked for possi ble trouble spots it s time to consid er an enclosure for the unit The author s unit was housed in a small metal enclosure Radio Shack catalog 270 253 measur ing 6 by 5 174 by 3 inches A 2 1 2 b
215. ing Place with PC Sound here haven t been any big changes to PC sound card architecture for some time now Sound cards are pret ty much all 16 bit stereo with 32 note polyphony and most of them use wave table synthesis But you will soon see some very different products coming on the scene including some of the first PCI sound cards You ll also see or rather hear true 3 D sound The L e ENE TUN Hardware AWE64 now has 64 voice polyphony and improved sound quality over the AWE32 It also provides hardware acceleration for DirectSound and Direct Sound3D While the AWE64 Gold is more sound card than most people need it s still relatively affordable and there s a non Gold version which costs 50 less that offers the same basic capabilities UTSUEE of i rsuii Of Perfeci Fidelity Arne Creative Labs Sound Blaster AWE64 Gold has 64 voice polyphony improved sound qual ity and hardware acceleration for DirectSound and DirectSound3D Not just an effect that opens up the sound field true 3 D sound is steered on the fly by what s happening on the screen For example if you steer to the left or the right of an object its sound can be steered accordingly If you shoot at something and blast it into five pieces each piece hurtling toward you can create its own sound track as it moves around you Even the most popular sound card in the business has changed Creative Labs new Sound Blaster AWE6
216. ion slide switch three LEDs and a standard bubble level The switch can be placed in off LED or LED audio mode In LED visual mode a level surface is indicated by the center green LED If either the left or right LEDs light up it means that either the left or right side of the surface is too high With the switch in audio posi tion no sound means that the surface is level Two different sounds indicate that the right or left side is too high the high XZ a X The ProLevel s flashing lights and audible beeps make easy work of leveling even when it is difficult to see the bubble Handheld PC The pocket sized Cassiopeia handheld PCs from Casio Inc S70 Mt Pleasant Avenue Dover NJ 07801 weigh less than a pound and come with the Microsoft Windows CE operating system installed That operating system ensures a high level of data compatibility between the Cassiopeia and Windows 95 based desktop computer and offers the same user interface as found in Windows for desktop PCs Model A 10 offers 2 megabytes MB of RAM and 4 MB of ROM which Model A 1 has 4 MB of RAM and 4 MB of ROM The Cassiopeia features a 480 X 240 dot backlit display a touch sensitive screen and a standard PC card expansion slot Other pre installed applications include Information Manager which is synchronized with Microsoft Schedule for Windows 95 Microsoft Pocket Word and Pocket Excel e mail capabilities Microsoft Pocket Internet Explorer
217. is a stereo circuit it needs at least 7 to 9 amps In _ON 9 _ 12 TO 17VDC St F1 R32 1502 J3 HEADPHONE JACK R31 15002 ee a q a a m a i ees M X ee i eee SPKR2 822 SPKR s21u01 29 3 seindod Z664 isnbny oO oi Popular Electronics August 1997 2 e2 my experiment tried supplying 12 to 17 volts at 10 amps and it worked well Switch S2 allows you to choose between stereo and moaural Closing S2 selects monaural operation and opening it selects full stereo reproduc tion Switch S3 selects the headphones or the speakers A heatsink should be used for both ICs If you are using an aluminum chassis for your enclosure you can use it as a heatsink but don t forget to use heatsink compound Jose Ignatius A Alea Philippines That s an interesting implementation of a balance control Again folks you can dispense with S3 by using a head phone jack that cuts the signal to the speakers Jose recommends using the next circuit as a preamplifier for the Power Amplifier Cebu Power Amplifier Preamplifier Here s an amplifier circuit see Fig 5 designed to boost low power audio signals such as the headphone output of portable CD players It is sufficient to drive a loudspeaker or a high input im pedance power amplifier This circuit not only amplifies it filters the input signal at the same time so you can hear the highs and lows clearly The
218. it Murphy s intermittent trap circuit is shown in Fig 8 This tester can be attached across a suspected intermit tent open connection in just about any circuit under test As long as there s no break in the external circuit LED1 re mains off However when the circuit be comes a little nervous and momentarily opens the SCR s gate receives a posi tive current through R2 turns the SCR on and lights the LED The LED re mains on until the power is removed by opening switch S1 Diodes D1 and D2 protect the SCR from reverse gate volt age and prevent a positive input voltage from the monitored circuitry from false triggering the tester The clock on the wall says it is time to hit the old kill switch for this visit All that ask is you keep these simple trou bleshooting circuits in mind the next time an electronic problem comes your way Who knows one of these might be the very circuit needed to outfox Murphy Good hunting until next month g Here s the ground fault interrupter was supposed to install yesterday Computer Bits Getting Organized O ne of my resolutions this year as every year was to get bet ter organized For that reason have been experimenting with several Per sonal Information Managers PIMs What is a PIM It s hard to define A given PIM may combine any or all of the following contact management and or address book classifications project planning and appointme
219. ith this simple test instrument and only basic electrical troubleshooting knowledge Fig 1 Just about the simplest automobile voltage tester around pe E T T E A EE V BO OO PARTS LIST FOR THE SIMPLE VOLTAGE TESTER Fig 1 4 Auto lamp type 1891 14 volt 40 mA eee Meter probe RadioShack 278 704 or equivalent heavy duty allige tor clip RadioShack 270 344 or equivalent etc obs z BE a tee ae ho L aig t wen YE o Been at Ben TB RE Pa a EO e eae E ok Es a a The second circuit shown in Fig 2 is a modern version of the first circuit but with a built in polarity indicator Here we have replaced the miniature incan descent lamp with two LEDs When the probe is connected to the positive volt age and the clip to the negative voltage source LED2 lights up When the probe and clip are reversed LED1 lights up Noting the polarity can be useful when troubleshooting in areas where a common ground is not easily accessible PROBE t l R1 2 pan a GREEN LED ALLIGATOR RED N CLIP Fig 2 This little auto voltage tester will note the polarity of the test voltage Green light is for positive voltage and red light is for a negative value 2 PARTS USTFOR _ THE VOLTAGE TESTER WITH POLARITY INDICATOR Fig 2 LED1 LED2 Light emitting diode Le any color or type Ai 470 ohm 4 watt 5 resistor Meter probe RadioShack 278 704 or
220. ities around the world a secret note area which is password protected and a full feature database program for addresses of unlimited record length Packed with options The PS 6800 Organizer is menu dri ven and provides for a host of user defined options inciuded in these is the ability to change the displayed informa tion into either English Spanish French Italian or German An indicator shows the status of the two lithium bat teries one of which serves as backup in a clever arrangement that lets you change either one without losing any of your valuable data Other thoughtful options iet you TEXAS INSTRUMENTS PS 6800 PERSONAL ORGANIZER Get organized and plan ahead You can even create and exchange information with your PC change the contrast level of the LCD screen set the date and time lock or unlock the unit with your chosen pass word set daily alarms and check on the amount of memory you ve used even to the next page The sound made by each of your keystrokes can be changed from a click to a beep or silenced if preferred The PS 6800 may be alone in its capability to allow address and phone number entries to run to as many lines as you wish This eliminates the need to create imaginative abbreviations that other organizers impose because of their rigid data entry format A Scan button lets you quickly browse through your entire database of names and addresses which are conven
221. itioning System receiver you ww Popular Electronics August 1997 don t have to worry about los ing your way But for casual hik ing biking camping Or even excursions into the next county there is a simpler and cheaper alternative the Hall Effect Electronic Compass The electronic compass described in this article uses a Hall effect sensor that can detect the earth s magnetic field and convert that informa tion into a directional indica tion Powered from a single 9 volt battery the compass is easy to build and makes a great learning project that will provide many hours of fun soiudsjoajy seindod Z661 jsnbny w w Popular Electronics August 1997 Q3 Fa Fig 1 Ar the heart of the Hall Effect Electronic Compass is a 1490 digital compass a unique magnetic sensor containing a miniature rotor on jewel bearings surrounded by four solid state Hall effect ICs The sensor is supported by a 74HC154 high speed CMOS 4 to 16 line decoder that s used to drive eight LEDs Circuit Description A schematic diagram of the Hall Effect Electronic Compass is shown in Alek 1 At the heart of the circuit is IC1 a 1490 digital compass a_ unique magnetic sensor available from Dinsmore Instrument Co 1814 Remell St Flint MI 48503 that is based on the Hall effect The Hall effect named for its discoverer physicist Edwin Herbert Hall is based on the principle that a volt age will dev
222. itors Vectorscopes EFP ENG Instruments w RF Signal Level Meters Audio Generators amp Meters Frequency Counters Meters amp Bridges Power Supplies Function Generators RF Generators PRINT Products International 2 Sma SOMA LEVEN weve 953 Ate ae eS ee ee Popular Electronics August 1997 Test Instruments Equipment Tools amp Supplies For Electronic Production Maintenance amp Service 8931 Brookville Road Silver Spring MD 20910 800 638 2020 Fax 800 545 0058 CIRCLE 47 ON FREE INFORMATION CARD O TURN YOUR PC INTO A OSCILLOSCOPES DIGITAL STORAGE OSCILLOSCOPE from 169 eee Respantive D Storage Multiecope ATC Q Scope uses printer port to turn PC AT into Digital Storage Oscilloscope Spectrum Analyzer Freq Counter Logger DVM DC 500KHz bandwidth 7i Sg lt p At right nmec a ve eo mM A amp rs cE Actual 8 p scope as Gales screen as w ae seen on H Ne your PC Qi i monitor yW Vy Ma pawl FEATURES Spectrum _ Dual channel external triggered _ Digital storage Windows based Connects to PC parailel port 20Megasamples sec sampling 10Mhz max analog bandwidth _ 8 bit resolution 8K RAM buffer Prog gain 10v div to 1mv div Spectrum analyzer fft function Strip chart recorder fun
223. iuddjoat3 seindog 7661 IsNbny d W Popular Electronics August 1997 amp BEST VALUES instruments avail able today Products international TEST INSTRUMENT CATALOG 1 Call fax or email today for your free copy of our test instrument catalog jam packed with the in test and measurement PRINT 8931 Brookville Rd Siver Spring MD 20910 800 638 2020 Fx 800 545 0058 Email SMPRODINTL aol com CIRCLE 46 ON FREE INFORMATION CARD ATTENTION CABLE VIEWERS CABLE VIEWERS get back to your BASIC Cable Needs Call 800 577 8775 For information regarding ail of your BASIC cable needs gt GOOD REASONS TO BUY OUR FAR SUPERIOR PRODUCT PRICE EFFICIENT SALES AND SERVICE WE SPECIALIZE IN 5 10 LOT PRICING ALL FUNCTIONS COMPATIBLE WITH ALL MAJOR BRANDS ANY SIZE orDER FILLED WITH SAME DAY SHIPPING FE yN H a We handie NEW equipment ONLY Don t trust last years OBSOLETE and UNSOLD stock COMPETITIVE PRICING DEALERS WELCOME ELECTRICAL W ARE HOU S l N G Refer to sates personnet for spechitations CORPORATION P O Box 8180 u Bartlett IL 60103 a 800 577 8775 HOURS Monday Saturday 9 5 C S T Digital Entertainment also available through WSkyvision neice swm gromt s di sk E TWO REK W 4Dv FOR C BAND BEST Values fram Skyvision Receivers Everything on the ar for co nplete vanety from 249 including 4DTV Enjo
224. ke testing some unknown equipment The lamps provide a safe method to limit current flow PARTS LIST FOR THE LINE VOLTAGE TESTER USING LAMP LOADS Fig 4 1 S4 SPST toggle switch 110 vots AC 10 amp RadioShack 275 324 or equivalent L1 Incandescent lamp 110 volts gt AC 40 watt L2 lncandescent lamp 170 volts AC 100 watt L3 Incandescent lamp 110 volts A 250 watt Fi 10 amp fuse PRAAN Fuse holder lamp sockets AC out Jet sockets power line cord etg Line Voltage Testers Our next two circuits are helpful in checking out equipment that operates on 110 volt AC line voltage If you fre quent hamfests and or search out the flea markets for neat old radios or test equipment you definitely need a non destructive way to check them out Why smoke test when you can safely check out your treasures with one of the sim ple circuits shown in Figs 4 or 5 if you don t have a variable trans former the circuit in Fig 4 is the least expensive way to go Three 110 volt AC incandescent lamps with different wattages are used to pre set current limiting Switch S1 limits the maximum short circuit current to about 360 mA S2 to about 900 mA and S3 to about 3 6 amperes The only drawback to this circuit is the high initial turn on cur rent of a lamp The internal resistance of an incandescent lamp is much lower when its filament is cold and increases greatly when hot That is where switch
225. l 30 MHz Frequency Counter 1 800 996 3837 Sen SS hex 0 00 TOLL FREE 1 800 99 METER L ON GOLDSTAR EQUIPMENT ANYWHERE IN THE U S Excluding AK amp HI LOWEST PRICES EVER New FLuke MuLTiMETERS amp TEKTRONIX OsciLLoscopEs The Industry Standard in Multimeters Textronix TDS Seniesl ON Sate ve Test Equipment Depot A FOTRONIC CORPORATION COMPANY P O BOX 708 Medford MA 02155 617 665 1400 FAX 617 665 0780 email afoti fotronic com e Sine Square Triangle TTL CMOS Outputs See us on the Web NOW MAKE AN EXTRA 600 PART TIME WEEKENDS UP TO 2 000 A WEEK FULL TIME IN Explosive SATELLITE DISH TV ELECTRONICS FIELD Hottest Career Opportunity Invention of the VCR See How Fast The Money Rolls In Part time Here s what you can eam over a typical weekend Install 2 Satellite dish systems at 20C 400 Repair 4 TV s at 50 each 200 Since RHA i tl f Tota Weekend Income Full time Working just five days a week you could easily earn Install 5 Satellite dish systems at 200 1 000 Repair 10 TV s average 50 each 500 Clean and adjust 10 CD players averege 35 each 350 Service 2 Home entertainment centers at 75 150 Total Weekly Income 2 000 In addition you can make big extra profits on other supplies you furnish Get in THE FAST LANE on the NEW INFORMATION SUPERHIGHWAY Everyone s Talking About
226. lab a 107 Vision Electronics 0000 0000 108 Visual Communications iire 16 Weeder Technologies 106 Weka Publishing 97 WPT Publications w92 134 Xandi Electronics 0 000 000 0000 89 AINN e a 86 ADVERTISING SALES OFFICES Gernsback Publications Inc 500 Bi County Bivd Farmingdale NY 11735 3931 1 516 293 3000 Fax 1 516 293 3115 Larry Steckler EHF CET President ext 201 e mail advertising gernsback Christina Estrada Assistant to the President ext 209 For Advertising ONLY 1 516 293 3000 Fax 1 516 293 3115 Larry Steckler publisher Arline Fishman advertising director ext 206 Michele Torrillo advertising assistant ext 211 Adria Coren credit manager ext 208 Subscription Customer Service Order Entry 1 800 827 0383 7 30 AM 8 30 PM EST ADVERTISING SALES OFFICES EAST SOUTHEAST Stanley Levitan Eastern Sales 1 Overlook Ave Great Neck NY 11021 3750 1 516 487 9357 1 516 293 3000 Fax 1 516 487 8402 slevitan26 aol com MIDWEST Texas Arkansas Oklahoma Colorado Arizona Raiph Bergen Midwest Sales One Northfield Plaza Suite 300 Northfield IL 60093 1214 1 847 559 0555 Fax 1 847 559 0562 bergenrj aol com PACIFIC COAST Mountain States Anita Bartman Hutch Looney amp Assoc Inc 6310 San Vicente Bivd Suite 360 Los Angeles CA 90048 5426 1 213 931 3444 ext 227 Fax 1 213 931 7309 BASIC STAMP
227. lass postage paid at Farmingdale NY and at additiona mailing offices One yecr twelve issued subscription role US ond posses sions 21 95 Canada 28 84 includas G 5 1 Concdian Goods and Servicos Tox Registration No 125166280 all other countries 29 45 Subscription orders payable in US fundi only International Postal Maney Order or check drawn on o US bank US single copy price 3 99 Copyright 1997 by Gernsback Publications Inc All rights reserved Hands Gernsback Publications Ine Popular Elactronies trademark is registered in US and Conada by Electronics Technology Today Ine and lea Gerrsbock Publications Inc Printed in USA 31u01 99 3 Jeindog Z664 isn6ny oh Popular Electronics August 1997 NO August 1997 ee ee PRODUCT REVIEWS 20 Hands on Reports Texas Instruments PS 6800 Personal Organizer 21 Gizmo WEBTV Internet Terminal DVD Debuts Panasonic DVD A300U DVD Player Pleasure Home Contractor Protape 16 Model HC 500 Prolevel Model HC 200 and much more COLUMNS 8 Multimedia Watch About the changes taking place in the world of PC sound hard ware Marc Spiwak 12 Net Watch Apartment Hunting Online Dan Karagiannis 15 DX Listening Is it Asia Is it Euxrope 2 Don Jensen 58 Scanner Scene Of Scanners and Things Mare Saxon 59 Ham Radio A Couple of Neat Things For Hams Joseph J Carr 61 Antique Radio This n That Marc Ellis 63 Think Tank Jose Returns
228. late common sense to say nothing of the Second Law of Thermodynamics Yet physi cists have theorized since the 1920s that bright light should be able to chill objects Usually when light falls on a solid object it deposits heat or energy However under certain cir cumstances light can absorb ener gy from thermal vibrations in a solid thus decreasing the object s tem perature When an object excited by radiation at one frequency can be caused to emit radiation at a higher frequency which carries more energy the net result is the object cools You can think of the principle here as something like cooling an object by washing it with cool light Continued on page 78 i HATE Lath i i vr T E O aa Pitas l i j i i amp b m s W a ee 4 ae y ee 1 l er ua i A Ss j 5 S Ls S 5 oe P 4 m r Pgs a WEE UR 1 Ae Here s a look at some new sophisticated software technology which enables persons with minimal vision or profound bearing loss urgery and corrective lenses L cannot help persons with minimal vision therefore they are legally blind Likewise even the best hearing aids are of little value to people with profound sen sorineural hearing loss New technol ogy based on the power of the computer can now help both the profoundly blind and deaf Allowing the Blind to See Again Advances in computer technology coupled with novel design in optical lenses pro
229. le routes of 15 legs six coordinate systems and differential GPS capability Users can go anywhere in the world and know their exact loca tion They can save that location in memory store the coordinates for other locations navigate between any of the locations or waypoints that are saved in memory The GSC 100 has a suggested retail price of 999 For more information contact Magellan Systems 960 Over THINK TANK Continued from page 66 tor R8 form a feedback loop Fuzz intensity is also controlled by R7 By adjusting the wiper position the amount of fuzz produced by the ampli fier changes The DPDT switch 51 bypasses the amplifier and turns it off for normal guitar sound It saves your D3 1N4148 LED1 a A 1N4148 land Court San Dimas CA 91773 Tel 909 394 5000 Fax 909 394 7050 CIRCLE 81 ON FREE INFORMATION CARD battery from draining when you prefer the normal sound of your guitar The LED is a simple on off indicator The circuit can also be powered by a 9 volt battery or adapter Jose Ignatius A Alea Philippines wish could hear that thing Between the clipping and non linearity of the diodes it looks as the circuit can real ly mess up an audio signal Cebu R13 ee 6802 100 D4 J2 OUTPUT Fig 6 This little fuzz amplifier circuit will put hair on most guitar signals Tapeless Videotape Cleaner The Trackmate Video HyperBRUSH is the worl
230. lectronics August 1997 oO I nan D March 1996 the output of U2 b was not drawn in the input is shown In fact the second half of flip flop U2 has no actual role in the circuit connected it as a divide by 2 of the clock for conve nience but the user can employ it in any way desired Clement S Pepper Parts Search read the article Build an Auto matic Headlamp Control which appeared in the February 1997 issue of Popular Electronics would like to build the device but I m having trouble finding parts Mouser Electronics says that the IRF9Z30 P channel MOSFET Q1 found in the parts list has been discontinued by Thomson No substi tution is listed Any suggestions I d also like to know where to get a heat sink like the one used by the author Mouser doesn t show anything similar Thanks B W Greenville SC lf you are unable to obtain the IRF9Z30 P channel MOSFET de scribed in the Automatic Headlight Control construction article a good substitute is the IRF9Z34 unit which is available from Digi Key Page 186 in the January February 1997 catalog General purpose heatsinks can be found from a number of sources Again try Digi Key page 161 If you still have trouble finding parts you can always obtain them from the author as indicated in the article Hope this ee KEEP IN TOUCH S Now there are more ways than ever t contact us at Popilar Feens ve gt You can write to
231. lications data transfer software and multiple platform real time DSP code The HAppi Wizard provides an exe the visual design user controls that represent inputs outputs and tunable parameters are used to accomplish I O Objects such as knobs sliders keypads meters and displays among others are typical user controls After a project is designed graphically the worksheet is saved as a file which is then applied by HAppi to create the 14 Windows application Popular Electronics August 1997 Sol ef xf ol pe waaka Secon cae toed E Oy FUNCTION GENERATOR Or bo j di Amplitude cutable version of their project Within The HAppi Wizard can be used for creating virtual instruments sharing simulation test results with others and creating easy to use real time DSP sys tems for non technical personnel Because the initial design is based on an open software architecture and employs a device independent DSP board driver users can create a virtually limitless number of applications It can be used in the design of such DSP based products as speech and telecom munications products arbitrary function generators modem test sets spectrum analyzers and other virtual instruments and multimedia applications cosh oe hk OW eS eS wih Hyperception Inc The HAppi Wizard costs Bee For more information contact Hyper ception Inc 9550 Skillman LB 125 Dallas
232. long wave band 140 425 kHz or thereabouts found on some receivers with coverage below the AM broadcast band Signals from J1 are fed through a length of coax to the signal inout DC output jack of the power supply circuit J2 From J2 the RF sig nal is AC coupled through C4 to J3 and on to the receiver Capacitor C4 is used to block DC while pass ing the AC signal Power is delivered to the preamp through the same cable that deliv ers the RF signal to J2 That power is supplied by an AC wall transformer connected to PL1 which feeds 12 to14 volts to a simple half wave rec tifier circuit consisting of D1 R7 R8 and C4 C7 Diode D1 rectifies the incoming AC voltage to provide a DC source that is filtered by C5 and decoupled by C while C7 acts as a bypass Construction The 100 kHz 30 MHz Active Antenna was assembled in two sections the preamp and the DC block We ll look at the preamp first The authors prototype of the preamp was built on a small print ed circuit board measuring 3 by m 3 1 8 INCHES Fig 2 The 100 kHz 30 MHz Active Antenna was assembled in two sections the pre amp and the DC block The preamp section was built on a small printed circuit board measuring 3 1 by 314 inches A full size template of that printed circuit pattern is shown here soiu0ioe1y seindog Z664 Isniny amp Popular Electronics August 1997 oO 124INCH TORQID od FINISHC
233. lows Zambia 4 910 kHz ZNBC has been heard at 0305 UTC with choral and calypso like music with announce ments in an African language oO CABLE CONVERTER DIAGNOSTIC TEST CHIP OAD FULL ACTIVATION OF CABLE CONVERTER WE STOCK A COMPLETE LINE OF CHIPS TOOLS WIRELESS QUICK INSTALL TEST BOARDS AND DIAGNOSTIC CUBES FOR ALL CONVERTERS ANYONE IMPLYING ILLEGAL USE WILL BE khk DENIED SALE WE SELL PRODUCTS ONLY To TECHNICIANS OR CABLE REPAIR FACILITIESI 1 IN CUSTOMER SERVICE amp TECH SUPPORTI ALL ORDERS SHIP WITHIN 24HRS UPS FED X PRIORITY NEXT DAY SHIPPING AVAILABLE SALE BUY TEST BOARDS AND GET FREE MON FRI 8SAM 7PM SAT 10OAM 2PM EST WEB i HT TPL WWw 800 GOCABLE on Bee VISUAL COMMUNICATIONS INC ORDERS CATALOG 1 800 GO CABLE KEEP YOUR C BAND SYSTEM BEST VALUES ON Receivers including 4DTV Dish Movers amp LNB s all kinds e Tune up Kits Tools amp Parts Skypac Programming e Toll Free Technical Help Fax 218 739 4879 1 Inet 21 8 739 5231 Frontier Dr i S90 334 6455 M ESkyvision The demand for computer programmers will double by the year 2005 Train now for a high paying career as a computer programmer Only NRI at home training gives you in demand programming skills in three of today s hottest computer languages BASIC C and Visual Basic d D Plus you now train with and keep 4 D state of the
234. m the differential output terminals at pins 4 and 5 is applied through a low pass RC filter to a differential ampli fier circuit A1 which supplies suffi cient boost to drive a loudspeaker or earphones The circuit in Fig 6A can use either an external oscillator for the LO or the internal LO stage Alternate output circuit schemes are shown in Figs 6B and 6C In Fig 6B the output signal taken from pins 4 and 5 of the NE602 is applied to the primary of an audio trans former Bypass capacitors C8 and C9 are used to decouple the RF sig nal while retaining the low fre quency audio signals Again the output signal must be fed to an audio amplifier circuit The output Circuit shown in Fig 6C is similar to those used on circuits presented earlier It consists of a m network low pass filter comprised of C8 C9 L1 The value of L1 should be 1 or 2 5 MH use 2 5 mH below 7 MHz The output capacitor C10 is used AUDIO OUTPUT C4 047 Lo INPUT SEE TEXT Fig 6 Another direct conversion receiver design this one using an NE602 double bal anced mixer DBM in the front end is shown in A The output of the DBM is fed to a dif ferential amplifier In B the output of the NE602 from pins 4 and 5 is applied to an audio transformer In C the output of the DBM is applied to a low pass n network filter TUNING fA VOLTAGE C11 D1 Fig 7 The illustration in A shows how to use an external inductor an
235. me digital components mentaMAX includes mentalSPICE This simulator is based on the Berkeley SPICE 3F5 simulator and allows you to do timing analysis frequency analysis DC curve analysis and others It comes with over 350 semiconductor and 250 IC models Signals can be introduced into a Circuit using a virtual function gencrator and the resulting waveforms can be viewed in th2 Oscilloscope window Digital Simulator For heavy duty analysis of computer interfaces timers state ma chines controllers and others mentalMAX provides the digital simulator SuperSIM This comes with 150 common TTL and CMOS models You can stimulate circuits with a built in virtual pattern generator and view results in a logic analyzer window You can also single step a circuit and monitor its progress using virtual LEDs and displays Circuit Board Layout Software mentalMAX comes with the popular SuperPCB program for do ing layouts on printed circuit boards up to 32 x 32 SuperPCB features mil 001 resolution 2 signal layers silk screen paste and solder mask layers It includes industry standard Gerber and Excellon outputs and you can also print your artwork on laser and other printers SuperPCB comes with 150 package parts for both through hole and surface mount devices you can add your own parts In many cases SuperPCB can automatically build a circuit board from just a SuperCAD schematic input using the built in autorouter and a
236. mits them without any wires by Charles Anton oday television choices T are virtually unlimit ed Between cable satellite TV videos and network programming it s almost a full time job trying to keep up with all the alternatives And it promises to get more complicated in the future Breakthroughs in fiber optic technology will bring over 500 channels into your home Home broadcasting breakthrough The problem with all this technology is the ex pense required to maintain your system and keep it up to date Now a wireless video broad casting system from Recoton gives you the power to utilize this technology without the hassle and expense of re wiring your entire home Today Recoton in troduces the next gen eration in wireless broadcasting The wire less video broadcaster transmits re broad casts cable TV VCR or satellite programs to any other TV in your home wirelessly Wave of the future Never drag your VCR from room to room again Recoton s wire less video broadcasting system transmits video or TV signals to any other TV in your home Because the system is totally wireless you won t have to worry about running miles of wires Besides who wants to install cable in every room of their home With Recoton s wireless video broad casting system you a security canera Wireless Video Breaktrrough Cable Broadzast cable channels even premium chanrebs to other TVs in you
237. mpli fier tubes with final output Power exceeding 1 500 waitts The AL 800 and AL 800H are de signed for legal operation over the range of 160 to 15 meters and can be user modified by licensed ham opera tors to operate on the 12 meter and 10 meter bands it is likely that some enterprising CBer will figure out how to make the antenna tune the 11 meter band but as we all know that s strictly illegal Both the AL 800 and AL 800H linear amplifiers feature a tuned input circuit output network tube protection those Eimac 3CX800A7 power amplifier network is a Pi Pi L design which is supposed to provide smoother tuning and a wide impedance matching range A heavy duty power supply particularly important in power amplifiers is fea tured along with a Step Start Inrush Protection design which limits initial inrush current means longer life for those expensive bottles The AL 800 and the AL 800H also have a grid circuit that limits grid cur rent and thereby protects the tubes Again as ads in this and other ham magazines demonstrate the Eimac 3CX800A7 power amplifier tubes are a major contributor to the price tag of lin ear amplifiers so any protection is well warranted grid current violations are a major murderer of RF power tubes whacked my share of a 6146B 807 1625 813 and an occasional 4 400A in my misspent youth when didn t understand grid current and overdrive The illuminated front panel meters
238. n the front of the box to alert users that mail is waiting Knowing that the terminal was not des tined for computer users ease of setup was of paramount importance If you can handle plugging something into a phone line and into the back of your TV you can hook up the WebTV terminal You don t need to know anything about modems and you don t even need to find the clos est number to connect the WebTV Net works it s all done automatically We still don t think that the living room Continued on page 30 DVD Debuts It s new it s hot and it s available Odds are you haven t spent the last few weeks camped out in front of your local Circuit City anxiously awaiting the day you could bring home your own DVD player In fact if you re not some one who goes out of your way to read about consumer electronics and you re not a regular reader of Gizmo you might not even have heard of DVD In fact you might not even know what DVD stands for which officially is nothing al though many people take it to mean digi tal video disc or digital versatile disc But you ll be hearing plenty now that several major manufacturers introduced DVD players It s been a long time coming but DVD has finally become a reality This month we review one of the first generation DVD players Panasonic s DVD A300U First though let s take a look at the for mat and what it might mean for you The DVD format off
239. natural inclination is to throw out the dead batteries and replace them with a set of fresh ones My advice is not to ditch those dud batteries Just because they don t have enough moxie left to 58 power a scanner doesn t mean that they re drained out You might be sur prised to find that such apparently dead batteries will still provide enough zip to operate small low current devices like remote controls for months HLTA CE Ma The former Regency Electronics now known as RELM Communications has re entered the scanner market with two hand helds including the HS 200 pictured here Another hint be wary of the accu racy of those self test meters provided on several brands of batteries They seem all too quick to pronounce bat teries in poor shape when in fact the batteries are a long way from quitting Manufacturers probably don t mind if customers replace batteries a bit soon er than necessary Mad Scientists on the Air Several exciting things that can be MARC SAXON monitored on scanners are given little publicity For instance you seldom get information about stations that the FCC licenses in the Experimental Radio Service For some unknown reason the subject never comes up Yet those off beat stations often repre sent new and unusual uses for radio The majority of experimental stations operate on microwave frequencies but here s a sampling of some recent ly licensed ones operating in t
240. nd a thin cable that connects the two units The speech processor is pro grammed specifically for the individ ual user by a trained hearing techni cian using Windows based software running on a personal computer Continued on page 76 Baby In A Briefcase Tests Newborn s Hearing The earlier a child with a hearing impairment is identified the sooner corrective action can start Hearing is critical in a baby s first years for prop er development of language cogni tive and emotional skills The Auditory Response Cradle ARC developed jointly by the Hillington Hospital and Brunei University in London provides very early screen ing when the infant is only a couple of days old The ARC looks like a large brief case with a built in cradle The just fed baby the optimum time for testing is placed in the cradle and earphones are placed on the infant s head A range of audio sounds are transmitted to either or both ears Responses to the sounds like turning of the head startling motions and other body activity is monitored by the pressure sensitive mattress and headrest Another sensor in a polyethylene band around the baby s abdomen monitors breathing The responses are recorded by the microprocessor in the ARC s computer The computer is programmed to detect lack of normal responses and automatically indi cates either PASS or REFER The entire test only takes a few minutes and is design
241. nd try out the antenna For best results your receiver should have a coaxial cable antenna connector If the receiver has a whip or other built in antenna dis connect it If a ferrite loop antenna is used for AM and long wave reception as is often the case you may have to disconnect the loop and substitute a suitable antenna coil s if you want the benefits of this antenna on those frequencies If SW reception is your main interest you can use the receivers built in AM antenna but then the active antenna will not benefit AM recep tion only shortwave reception set receiver to AM broadcast Tune in a signal Note the S meter reading if your receiver has one If not tune in a weak signal You should hear signals as well or better than you would using a 20 foot length of wire on the floor Next place the antenna outside the building or if this is difficult you can place it in a window If all is OK a number of strong signals should be heard and performance and reception of standard AM broad casts should be similar to a good Bor mss e ee Fata T ma a i Ee et eel BS ll sm ee a i rh th iJ a gs tre oa m E fe eer The printed circuit board is mounted into the PVC coupling by way of the board mounted F connector a couple of washers and hardware This holds the board rigid ly in an upright position as shown here so that the unit s PVC tube housing can easily be slipped into position over it PA
242. ned with computer simulations indicate that a fluores lt Rippers ti a Optical Fiber Dielectric Mirrors t a device that s been shown to generate extreme ld Well science has found a way to do Just that Radiation Shielding In this conceptual design for the Los Alamos Solid State Optical Refrigerator a pump light supplied by a laser diode is carried through an optical fiber and enters the optical refrigeration element ORE through a small hole in one of its mirrored surfaces The mir rors trap the light in the ORE until it is absorbed and then re emitted at a higher energy level The ORE cools and the higher energy light escapes and is absorbed by the walls of the vacuum casing Radiation shields that transmit the higher energy light but block ther mal radiatian from the vacuum casing keep the ORE cool through an inverse greenhouse effect The abject to be cooled is attached to a cold finger connected to the ORE cent cryo cooler could operate for years with efficiencies and cool ing Powers comparable to current commercial systems The cryo cool er however boasts several improve ments it would produce no vibra tions since it has no moving parts it would neither generate nor react to electromagnetic interference it could cool to 77 K weigh less than 3 kg watt and could operate con tinuously for 10 years Using laser heat for cooling may at first seem to vio
243. ng curriculum provides the most powerful teaching learning tool for electronics available today This complete electronics program includes on line instruction and testing workbooks and virtual labs Best of all you do not have to purchase any expensive laboratory equipment to have an exciting and accurate electronics training program CircuitMaker CBT will help the user learn and un derstand electronics and troubleshooting of both analog and digital circuits We guarantee it CircuitMaker 299 TraxMaker 299 At MicroCode Engineering we are committed to total customer satisfaction When you purchase one of our products you have the confidence of knowin g that a trained staff of professionals is available to serve you after the sale Our free unlimited customer service is second to none Whether you have general or technical questions they will be answered promptly by a knowledgeable representative FREE Functional Demo Additional literature and tree functional demos of our products are available on the Internet at http www microcode com and on CompuServe GO MICROCODE MicroCode Engineering Inc 92 CircuitMaker CBT 75 per module Call now to order or request additional information 800 419 4240 Fa 70 Fax 801 226 CIRCLE 171 ON FREE INFORMATION CARD 532 Internet http www microcode com
244. nnects to mono or Stereo FM transmitters and produces a powerful 2 15 watt signal which could broadcast up to 5 miles or more Requires 50 150 mW drive A Step by step plans complete with part source I information and antenna designs ONLY Pe Progressive Concepts p BOX 586 STREAMWOOD IL 60107 As 22 Ee FAX 630 736 03523 PLUS 2 S amp H NO C 0 D 5 CABLE TV CONVERTERS Equipment amp Accessories Wholesalers Welcome Call C amp D ELECTRONICS 1 888 615 5757 M F 10a 6p 195 00 Mobile Robots Book 40 00 10 academic discount Quantity discounts available Call for international and quantity shipping charges 7 50 S amp H charges for USA and Canada IL residents add 6 25 sales tax to total Tel 309 382 1816 Fax 309 382 1254 www lynxmotion com jfrye lynxmotion com MISCELLANEOUS ELECTRONICS FOR SALE EE TT THE Case Against Patents Thoroughly tested and proven alternatives that work in the real world 28 50 SYNERGETICS PRESS Box 809 C Thatcher AZ 85552 520 428 4073 Visa MC _ FM Micro Broadcasting 88 108MHz Assembled PLL transmitters and rf amps mono stereo 1 2 100 watts Photo ree o call 250 642 2858 R SCOTT COMMUNICATIONS LTD We ship world wide from Canada orld wide trom yanasa SERVICE offered to international clients We lo cate acquire ship U S technical vendor informa tion equipment systems parts to you worldwide T
245. nnects to your telephone wall jack Decodes all 16 touch tones and displays them on an LCD display Holds the last 240 digits In a Nnon volatie memory croll through and view all telephone numbers dialed credit card numbers entered etc 54 50 OWN A MACHINE SHOP The Smithy z ee e 2 Lux Sensitivity e Undetectable Lens Jathe mill A pi DETECTS o Body Wires Transmitters you i 3 Body Wires e Tape Recorders Video Equipment a j e FM Wireless Mics tools in one easy to use e AM Transmitters pret rechne Saenes Ml UH Transmitters Call for your FREE Info Pak 1 800 345 6342 Ask for Operator PE78 DETECTS or write e Ad Phone Taps Dept PE78 L e Ail Body Wires e Ail Transmitters DISRUPTS die isk ones e 380 H TV Lines Ys ALL TRANSMITTERS amp Bopy WIRES Write Noise SIGNAL BREAKER ft gt Buy recycled ee 1 FEATURES e FCC Approved 2 4GHz Transmitter Receiver e Radio w Built In Color Camera Transmitter e 380 H TVL Resolution Super Low 2 Lux e 4 Channel Receiver 300 Transmission Note Cassette Player Non Functioning It would mean the world to them Recycling keeps working to protect All 300 Series Color Cameras Feature Superior Resolution Over 380 H TV Lines Super Low 2 Lux Sensitivity 3
246. nology is an excellent first stop on your search for a place to call home The database is free and easy to use and can help you find a place to live in one of 1 200 cities When you first log onto the site you are presented with a few choices The link most people will click on is the Unfurnished Apartments one but you can also select from Temporary Fur nished Suites International Rentals 12 and Self Storage Facilities Popular Electronics August 1997 AT gree in minia baib ae belch Wf ce ee Tenera man PE EEE alates Snt Ae aa a j Ma ai ae ane A aa a nan erry One of the most innovative features of Rent Net is its use of the Total View BubbleViewer which lets vou take a 360 degree tour of the rooms in an apartment Unfurnished Apartments lets you choose where you would like to begin your search Click on a state or province and you re on your way You ll then get to choose what type of place you are interested in studio through three or more bedrooms and then pick from various price ranges Once you have made a realistic selection a list of links showing possible places for you to live will then come up on screen Each apartment will have a checked off list of amenities such as whether the place has air conditioning E erties lbe Hirian Apartmens One Bedrna e ee ii aay DAN KARAGIANNIS parking or even a pool Below this are several paragraphs worth of informa tion that shoul
247. nsmitting Atternpting to transmit with this anten na will destroy the preamplifier and May also damage the transmitter Ge ages using a DVM or VOM Connect the negative lead to the negative lead of the power supply Voltages are specified assuming a 13 volt DC input This can vary 20 so you may see some proportionate varia tions in these readings There should be 13 volts at the collector of Q2 and the drain of Q1 if not check the connections to TI and C2 2 3 volts at the junction of R2 R3 if not check the connections to those compo nents there should be 2 8 4 2 volts at the source of Q1 if not check Q1 R2 then check that 2 3 volts appears at the junction of R2 R3 if not check R2 and R3 and finally check Q2 for 2 1 3 5 volts at its emit ter if not check Q1 Q2 R5 C3 Next check out the DC block as follows Apply 12 14 volts AC to PLI You should measure 17 to 22 volts at J2 and zero at J3 Remove power and momentarily short C with a lead to ground A spark should occur Next connect an ohmmeter between J2 and the junction of C6 C7 You should read 129 ohms 10 The reading from PLI to J3 should be infinity That completes the DC block checkout Temporarily assemble the antenna without cementing any of the plastic parts together The parts will fit snugly together without cement and hold well enough for temporary use Connect the antenna assembly DC block and receiver as outlined in Fig 7 a
248. nt scheduling task tracking and prioritizing e mail management utility functions such as calculator phone dialer and URL track er and organizing large amounts of miscellaneous information The hardest part of picking a PIM is not choosing one It s figuring out what your needs are For example do you need a full blown contact manager or would a simple address book suffice A contact manager takes a rigorous approach to tracking every single communication with an extensive list of contacts whereas an address book is usually a simple database of names addresses and telephone numbers Sales personnel are usually most inter ested in full blown contact manage ment however an address book will usually suffice for the rest of us Having said that it is important to point out that not all address books are the same The number and type of fields the abil ity to customize and add fields and other features these vary all over the place This month and next I m going to talk about my PIM selection process and several specific software products Outlook 97 InfoSelect 3 0 and Ecco Pro 4 0 published respectively by Microsoft MicroLogic and NetManage This is not going to be a product review per se Rather it will be more of an ex ploration of the issues involved along with some specific tips on how different products address different issues Primary Needs and Wants For years have tried various home brew
249. nta tion and QBasic Software Gets You Running FAST Counts as 2 Devices on the NCD RS 232 Network use up to 8 GDSPs ona single Seria Line Many Price Options Available 99 299 Includes Drivers in QBasic Mac G Amiga Software 1 Also Supported National Control Devices Contact Ayan Sheldon Phone 404 244 2432 FAX 417 646 8302 Include 5 Shipping Visa MC Accepted NCD Box 384 Osceola MO 64776 i Infrared Transceiver for Remote RS 232 Communication with 16 IR Controllable Devices High Power DC Motor Con troller 9 12 Volt Operation for Motors Up to 4 Amps Forward Reverse 64 Speeds With Infrared Receiver Hexfet H Bridge Driver stage NCD M1 Kit 89 Asm 149 grammable Outputs Pulse Width Mod Period Measurement Use as a Digital Tachometer Optoisolated RS 232 Networkable Easy to Pro gram Requires 12 RSB booster NCD ADS Kit 34 Assembled 49 TEF R si ia at A TNA Audio Video Switcher 8 In puts 2 Outputs Controllable Routes Any in put to Any Output 12 18 volt DC operation For Low Power Line Level Signal Switching Routeing of Most Analog Sig nals AVS8 Kit 89 Asm 139 Infrared Devices Nir AS 232 Networkable iA AET T am 8 Relay Driver cludes 8 LED Status Lights 12V Operation Includes Infrared Receiver for Remote Operation Attach 16 per serial port With Omron Mechani cal Relays 4 Relay Model available R85 5A Kit 89 Asm 139 R810 10
250. o along with this but we cost reduced the Type RS cabinet from about 7 to less than 1 It then became the Radiola lil and we built thousands of them In fact we proba bly sold more of them than any other type used to wonder why my grandfa ther called the RF the Aeriola Senior when most of the texts had seen called the RS a Senior Following my grandmother s death in 1995 my father and cleaned out the house and found a large quantity of papers from SMALL CAPACITOR SEE TEXT jj L Fig 1 A small capacitor connected as shown to the antenna segment of the Star Roamer s bandswitch makes an outside antenna work on the broadcast band The drawing of the bandswitch is a copy from the original manual Aerola Sr RF from Radio Manufacturers of the 1920 s Westinghouse that my grandfather had saved Among them was a notebook containing outer shipping labels and inner instruction cards for all Westing house home use radio production for 1921 and 1922 They are pasted onto Westinghouse watermarked paper and many labels are stamped with a circular time and date received stamp The dates range from mid March 1921 to August of 1922 All of the labels and instruction sheets for Aeriola Seniors show that MARC ELLIS they are designed as Type RF They are all shown as one tube receivers Alan Douglas in Radio Manufacturers of the 1920 s Volume 3 shows an Aeriola Senior RF on pages 6 and 11
251. o change without notice Prices are U S prices only prices in other Countries may vary 0497PESR CIRCLE 156 ON FREE INFORMATION CARD CircuitMaker Schematic and Simulation TraxMaker PCB Layout and Autorouting CBT Computer Based Training The Only Complete Virtual Electronics Lab FES landden gt ltk Oe uf 7 5 batan RE 7 3 ji Em EFIR er oe f Wee tS Scatter is a Sy UNDAMENTAL LOGIC ELEMEN y Cr CUNDAMENTAL LOGIC LEEMFHIS UNIT OBJECTIVE Al the completion of this unit you will be able to determine the inpnt output relationship of AND NAND OR and NOR logic gates by using the DIGITAL LOGIC FUNDAMENTALS circuit board Si oat Maker Total Customer Satisfaction CircuitMaker 5 The Fastest Most Accurate True Mixed Signal SPICE Simulator CircuitMaker is a virtual electronics lab where you can quickly and easily desig and verify digital analog and true mixed mode circuits You layout your circui design as a schematic connecting an assortment of over 4000 indestructible com ponents Click on the simulation button and view the results as if you were looking at real laboratory instruments It really is that easy New users love CircuitMaker s user friendly environment and short learning curve Experienced users appreciate its time Saving features and respect its accurate simu lation and numerous in depth analysis capabilities No matter what level of elec tronics you are at
252. ol an adapter for your portable CD player We can provide accessories that will nelp you get the most erjoyment and geat ast benefit from thousands of products No matter who made it or where you bought it you already know who ll get you connected For our stare near you Call 1 800 THE SHACK R RadioShack You ve got questions We ve got answers C RCLE 14 ON FREE INFORMATION CARD Popular Electronics August 1997 Buyers Budget Books Better Buys BP294 A Con cise Introduction to Microsoft Works 6 95 In the shortest and most effective way yOU can use the word processor to advantage to type edit print and save documents It goes on to explain how Works can be used to build up simple Spreadsheet examples edit them save them print them and retrieve them It informs you how to create simple macros and enables you to simplify long repetitive tasks and to customize the program to your own needs A Concise introduction to _ Microsoft Works MRT ORB SP RM Oe Boe Opto Electronic Projects 5 95 if you shun opto electronic projects for lack of knowledge this is the book for you A bit of introductory theory comes first and then a number of practical projects which utilize a range of opto devices from a filament bulb to modern infrared sensors and emitters e coe Board Games 6 00 Twenty novel elect
253. old At the heart of the system is a six channel two front two rear and two center A V amplifier with ten surround modes and twin mode DSP front normal Its Artificial Intelligence Field Control system automatically adjusts the surround field and mode based upon the surround information embedded in the software being played The AM FM tuner includes a three program timer and allows you to enter station call letters or name for instant recall A CD player and double cassette deck are included The system s magnetically shielded speakers use a rear ported bass reflex enclosure design with curved corner edges for maximum sound dispersion Price 1799 Thermal Fax Machine Sharp Electronics Corporation Sharp Plaza Mahwah NJ 07430 2135 offers a less expensive but feature laden alternative to plain paper facsimiles with its Mode UX 187 thermal fax machine Compact enough to use anywhere in the home the UX 187 also offers features attractive to home office workers Its PC Link allows users to turn the fax machine into a printer or scanner by con necting it to a personal computer and a PC s fax modem and software elimi nating the need to buy a separate printer scanner and fax The UX 187 supports caller ID and distinctive ring detection to help manage incoming calls on up to four telephone lines using services offered by local phone companies It offers 64 levels of gray which retains graphic detail quality A super fine resoluti
254. omputer inter laced display By not sending video that is better than can be appreciated on a TV performance is improved VideoFlash however is not based on P the Internet protocol Therefore it won t work on the Internet but it will work only on WebTV Network s propri etary network Industry analysts think that WebTV could end up fracturing the Internet in two one half being a tradition al computer centric Internet and the other being a TV centric Internet with loads of multimedia the kinds of things you re used to seeing when you turn on your TV For example instead of calling up a Web page just to check the latest scores you could call up a page and see not only the scores but the game high lights too The fracturing of the Internet might not be the worst thing in the world Moving some of the most popular sites includ ing CNNs and ESPNs from the tradi tional Web and onto a proprietary net work that can do a good job in delivering video might just open up some space for the rest of us Even without video WebTV Networks and the Philips Magnavox WebTV termi nal have some good things going for them For example the box is smart enough to keep an ear out for call waiting signals When it hears one it can hang up and let the call come through When the call is finished the box can automatically connect again to the service It can auto matically check incoming e mail periodi cally and flash a light o
255. on setting improves the transmission image and clarity of detailed documents Price 399 99 ELECTRONICS WISH LIST Sansui AH 7 Mini Component System ri ji ita 1 E IRIE Hi a iw be t i R J k da ig i 4 f 2 b i i a i To i Sharp US 187 Fax Machine 29 Popular Electronics August 1997 a So ON AN EVEN KEEL Continued from page 28 er pitched sound is for the left side We rarely used the audio mode the sounds which are made whenever you move the ProLevel are just too annoying Instead we relied upon the three LEDs and of course the good old bubble We went around our entire office examining every work surface and never got a sin gle green light Even when the bubble ap peared to be centered the LEDs would flash green red green and always end up in the red A bit like our checkbook In fact we were able to get a green light only on a stack of papers sitting atop a desk that had proven to be uneven At first we thought that the entire office was built on a slant but some surfaces sloped to the left others to the right Besides when we finally got around to checking out the floor it was level Oh well none of the computers are sliding off our desks so we won worry too much about that A ruler protractor is built into the ProLevel The knob at the left side of the device can be loosened to allow the ruler to swing up or down Small round win
256. on of the retina tometric optic and laser systems In this application Soltis uses data from several different measure ments of the eyes to determine the optimum prism parameters and level of magnification needed to maximize vision The Soltis calcula tions which take only about five minutes result in about a 95 per cent accuracy The software also calculates the eye s physical para meters and most importantly the location and size of the portion of the retina that is still functional Input data to the Soltis software includes measurements of the external radius of the patient s cornea Data on eye parameters are also determined using a variety of optometry and ophthalmology techniques such as echography or sonography angiography and retinography The precise location and size of the portion of the eye that is still active is determined by using a dual laser scanning taser ophthalmoscope SLO One laser of the SLO projects an optotype image onto the retina The second laser scans the retina to locate the precise area that reflects the opto type Areas of the retina that reflect are the portions that are still active and with properly designed lenses they can be used for vision The results of some five years of research are quite impressive The technique has been used to design glasses for patients of wnom 80 per cent were over 75 years old with the rest being younger than age 15 The test group women
257. once again The soft cover book has 317 pages It costs 12 95 plus 1 shipping and handling book rate mail UPS ship ping is available for an extra cost Illinois residents add 1 sales tax Write to Lindsay Publications P O Box 538 Bradley IL 60915 In the Spring Supplement 1997 catalog included with the review copy of 1928 Radio Trouble Shooting Lindsay also marked a two page spread announcing another new reprint the 1912 edition of Maver s American Tele graphy and Encyclopedia of the Tele graph The 700 page classic reference contains 34 chapters including 544 illustrations detailing the state of the art of that technology as it was in the early years of the century It looks like a very important book for those who are inter ested in the history of telegraphy The hard cover book has over 700 pages It costs 34 95 plus shipping and han dling and tax as mentioned above Tube Lore Supplement just received a note from Lud Sibley author of Tube Lore which was reviewed in the February 1997 column Thanks to a great deal of interaction with readers of the new book not to cy nen Whee o g alt mention his ongoing research Lud has acquired enough additional material to publish an eight page supplement The supplement is included with all books shipped since mid February Those who received their books ear lier can get a copy in one of two ways 1 Send a business size self ad dr
258. ortunately you ll aiso find a few really cheap ones that have minor maifunctions For example you might find a telephone that has audio and produces tones but won t access the local telephone Office Or maybe the phone won t produce any tones at all i f you d like to add an extension A Little Background In a fully func tional tone phone pressing a num bered button on its key pad acti 54 vates a pair of oscillators in the WILLIAM K MCKELLIPS phone that produce two special audio tones one for the row and the other for the column If the fre quency of one or both of the tones is not within tolerance then the local telephone switching center will not recognize the tones and will either connect you to the wrong number or simply ignore your signal altogether If you simultaneously push two buttons in the same row on most tone phones you will get a single frequency tone the row s oscillator frequency If you push two buttons in the same column of the pad you will get that column s oscil lator frequency That gives you an easy way to separate the row from the column tones thereby allow Ing you to independently measure each of the pad s audio frequen cies And that s where the DTMF Frequency Counter described in this article comes into play iN addition to the DTMF Freq uency Counter you ll need a regu lated 5 volt power supply If you already have one you can build the DIMF Frequency Counter fo
259. oton system is like adding a gt cable box VCR i and satellite dish to every TY t in your home Video Broadcasting System 99 9 S amp H includes one transmitter and one receiver Additional receivers each 59 7 S amp H Please mention promotional code 173 11046 For fastest service call toll free 24 hours a day AMERICAN PRESS To order by mail send check or money order for the total amount including S amp H VA residents include 4 5 sales tax Qr charge it to your credit card by enclosing your aecount number and expiration date Bini Had INDUSTRIES 2820 Waterford Lake Drive Suite 106 Midgothian Virginia 23113 21u01 28 3 seindog 7661 isnbny 0O Popular Electronics August 1997 i O WHERE TO GET IT Access Software 4750 Wiley Post Way Building 1 Suite 200 Salt Lake City UT 84116 800 800 4880 801 359 2900 http www accesssoftware com CIRCLE 60 ON FREE INFORMATION CARD Books That Work 2595 E Bayshore Road Palo Alto CA 94303 800 242 4546 415 326 4280 http www btw com CIRCLE 61 ON FREE INFORMATION CARD Broderbund Software Inc 500 Redwood Bivd P O Box 6121 Novato CA 94948 800 548 1798 415 382 4400 http www broderbund com CIRCLE 62 ON FREE INFORMATION CARD Comfy 305 Madison Avenue Suite 1165 New York NY 10165 800 99COMFY 212 599 2000 http www comfyland com CIRCLE 63 ON FREE INFORMATION CARD Creative Labs 1901 McCarthy Bivd
260. output Select a fuse size that matches the transformer s maximum output current If you are planning on checking out old radios or other low powered equipment select a low wat tage lamp for L1 Here s one method to use in check ing out a piece of electronic equipment that hasn t been powered up in years Set T1 for a minimum output voltage and set switch S2 to position B Plug the UUT into the outlet and turn on switch S1 Slowly increase the voltage by varying the tap on T1 while watching L1 If there is a short in the UUT s power supply L1 will light up big time If L1 only barely glows everything is probably okay Transformer Tester Our next test circuit shown in Fig 6 can be used to check out unknown power and audio transformers for Shorted windings A transformer wind ing may be checked with a VOM for continuity and in some cases to deter mine the primary and secondary wind ings However a VOM cannot indicate if the unknown transformer has a short ed winding A single shorted turn in either the primary or secondary win ding can render the transformer use less ECTION paddies ae ie TRANSFORMER UNDER TEST Ropes oe T A iy e i L i PUSHBUTTON N O 2 ALLIGATOR CLIP Bt 1 Fig 6 This simple circuit provides a unique method to check out transformers for shorted or defective windings PARTS LIST FOR THE TRANS FORMER TESTER Fig 6 NE1
261. p in arms when it was announced that the CIA parent organi zation of the FBIS intended to cut its budget by 25 percent FBIS since the early days of World War Il has done professionally what you and do as a hobby listen to shortwave stations FBIS monitors translates and publishes accounts from about 3 500 foreign broadcast and press outlets in 55 languages These reports are used by govern ment agencies for a variety of purpos es During the 1962 Cuban missile crisis the FBIS monitoring of R Mos cow gave president John F Kennedy the first news of the Soviet decision to withdraw missiles from Cuba an act that may have averted a nuclear war Most FBIS reports are far less dra matic and many private sources such as universities draw upon their trans lated data as well So reports that the CIA was planning cutbacks brought heavy criticism About a year and a half ago FBIS ceased publishing paperback volumes of its foreign broadcast and press translations Currently subscribers pay about 50 for a subscription to a Web site version of the translations Would the budget cut reduce services even further users worried Apparently not The CIA spokesman has announced that FBIS will continue its present level of coverage at virtual ly 100 percent Down the Dial Looking for some interesting sta tions to tune Try these Remember that the schedules given are in UTC i j Pics ae
262. pability TZPC175DG2 89 85 82 Our Top of the line converter with volume control Featuring sleep timer standard HRC switchable parental lock last channel recall favorite channel memory and 83 channel capable PHONE 810 566 7262 FAX 810 566 7253 MO TECH DISRIBUTORS YOUR MIDWEST PANASONIC CONVERTER WHOLESALER CABLE T V Converters amp Equipment WISE PRODUCTS 30 day money back l year warranty Dealers Welcome 1 800 434 2269 Visa MC Amex COD Patas Wholesale Wholesale distributors of cubes and one piece units works on all major systems call us last for the best price 300 753 7277 COMPONENTS STEPPER C EDE1200 is etc E LAB DIGITAL ENGIN erfect for robotics ERING INC 712 944 5344 www netins net showcase elab D p Delievably widespread Electronic Devices with amazing capabilities can be monitoring your telephone and room conversations RIGHT NOW Are you f sure you re safe FREE CATALOG telis you fast Inciudes Free Bonus details on fantastic opportunities now open in Counter Surveillance field Exciting immensely interesting and EXTREMELY profitable up to 250 hr full part time income Call Now Technologies PO Box 421 Batavia OH 45103 Home Automation Connects between a TW523 and an RS 232 serial port Use your PC Mac to recelve and transmit all X 10 comman
263. pay now i electronics repairs at home at a UPDATED by check or credit card and save 10 off the regular price plus the fraction of repair shop costs 6 50 shipping amp handling If tm not 100 satisfied may return Whether you enjoy doing your SUPPLEMENTS the book within 30 days for a full refund of the purchase price own repairs or want an extra part About 4 5 times a year we ll send Jm SAVE Bill my credit card 49 95 time income this famous nationally you updated 140 page repair sup l advertised WEKA ELECTRONICS plements for all the newest elec REPAIR MANUAL gives you easy tronic products available Examine i to follow instructions for fixing near these supplements at home FREE i ly every electronic device you can for a full 30 days If you decide to Phone ___ i think of from popular manufactur add them to your Manual theyre 1 SAVE My check is enclosed for 49 95 ers like SONY RCA IBM NINTENDO yours for just 35 00 each plus Ada 10 00 for EXPRESS DELIVERY guaranteed within 5 business 1 l J l l l l 1 f i l l I l I l I j I I I I I I I I 4 Ovisa C MASTERCARD Exp Date _ i Account ETENE w a L Signature and more Plus you get more than shipping and handling Theres NO days from receipt of order Prepaid U S A orders only no PO Boxes just easy instructions YOU GET A RISK NO OBLIGATION ORDER
264. play or connected to a PC with the optional upgrade 49 95 The Upgrade includes an RS232 serial port amp cable 32K of battery backed RAM amp Assembler Terminal software e Measuring Temperature e Using a Photocell to Detect Light Levels Making a Waveform Generator Examples Constructing a Capacitance Meter Include Motor Speed Control Using Back EMF e Interfacing and Controlling Stepper Motors e Scanning Keypads and Writing to LCD LED Displays e Bus Interfacing an 8255 PPI new Using the Primer as an EPROM Programmer The PRIMER is only 119 95 in kit form The PRIMER Assembled amp Tested is 169 95 Please add 5 00 for shipping within the U S Picture shown with upgrade option and optional heavy duty keypad 29 95 installed L25 x us 2P n a ii 1985 1997 cl AL INC 73 Street Smart Security 800 908 4737 11 EMAC WAY CARBONDALE IL 62901 7147 University Avenue La Mesa CA 91941 Send Fax or Call Order In Use Credit Card or Check Fax 619 462 0652 YEARS OF SERVICE 618 529 4525 Fax 457 0110 BBS 529 5708 World Wide Web http www emacinc com S31U014994 3 sejndog Z664 Isnony Learn MICROCONTROLLERS EMBEDDED SYSTEMS and PROGRAMMING with the AES learning system embedded control system Fa THREE MODELS AVAILABLE Choose from an intel 8051 intel 8088 or Motorola
265. quipment Black leatherette exteri S or with separate zippered compartment for papers or accessories Detachable nylon web shoulder A75 Interior space is 13 5 X 9 X 2 5 CAT CSE 12 fo AUTOMOBILE VOLTA mee mee VERTER CHERRY D43 SNAP ACTION SWITCH S P D T snap action switch with PA roller positioned above switch actuator Rated 5 amps YA 125 250 vac Switch body 1 1 Gin x 0 63 x 0 375 Solder or qc terminals UL and CSA listed i aji CAT SMS 150 12 each 10 for 10 00 SMALL NEODYMIUM RARE EARTH MAGNETS Semi circular irregularly shaped magnets Shiny finish with a polarity marking dot 0 93 long x 0 3 x 0 07 hin thick Powerful for their size u mnn g operated devices from your car cigarette lighter Regulated DC DC con verter supplies selectable volt ages from 1 5 Vdc to 12 Vdc at up to 800 mil liamps Adjustable polarity Includes six different ep s adapter plugs that fit 00 al alin sl most equipment 400 each 160 pes 100 00 each as CAT APC 800 MINIATURE MINIATURE SOLENOID Bicron Electronics CF 3 5 vdc miniature solenoid with spring HI 8 VIDEO CASSETTE g USED _ SONY Hi 8 Top quality metal particle 120 minute video a il a z cassettes Used for a short x U aa ai j time then bulk erased Suitable for Each cassette has its own plastic storage box CAT VCU 8 Satisfaction Guaranteed
266. r Unfortunately a software synthesiz er needs assistance from a CPU so the AWE64 cannot be installed in any thing less than a Pentium 90 Creative WaveSynth uses Sondius WaveGuide technology which incorporates mathe matical modeis of real instruments to generate sounds The AWE64 also offers 3 D Positional Audio which lets it steer sounds bundled software demonstrates this effect The AWE64 Gold has 4 MB of RAM upgradable to 28 MB but only with Creative Labs memory modules and not with standard 30 pin SIMMs like the AWE32 The plug and play card installs in a 16 bit ISA slot It has a line input a microphone input a joy stick MIDI connector and gold plated line level RCA output jacks The SPDIF output is located on a separate bracket with a cable connecting it to the sound card Bundled software applications include players and recorders for all types of multimedia files control paneis for the sound card a mixer a program that lets you link and embed sound files into other doc uments text readers voice recogni tion software and so on But the best thing about the AWE64 Gold is how good it sounds It s got the best sound ing MIDI I ve ever heard from a sound card If you ve got the 249 then go for the Gold New breakthrough clones TV signals and sends them to any other TV in your home Recoton s new development duplicates cable TV VCR and satellite signals and trans
267. r about 16 00 even if you have to buy every part new For those of you who don t have a power sup ply we ll present a simple regulated power supply that you can incor porate into your unit for a just few dollars more The DTMF Frequency Counter uses a quartz crystal taken from a digital watch for its frequency stan dard You probably have seen brand new digital watches for chil dren selling for less than a buck at large drug or discount stores Better yet you may have a cast off digital watch in a junk drawer When you open the back of the watch this may take some doing you ll find a small tubular can with two tiny wires sticking out of one end That s the timebase crystal which is designed to oscillate at 32 768 Hz TO TELEPHONE UNDER TEXT Fig 1 The DTMF Frequency Counter is built around six integrated circuits IC1 a 555 oscillator timer 1C2 a 7400 quad 2 input NAND gate 1C3 4553B 3 digit BCD counter IC4 a 7447 BCD to 7 segment decoder driver IC5 a 4060 14 stage ripple binary counter divider IC6 a 74LS393 dual 4 bit binary counter four FND507 common anode seven segment displays DISP 1 DISP4 and a handful of support components Circuit Description A schematic diagram of the DTMF Frequency Counter is shown in Fig 1 The circuit is built Ground six integrated circuits IC1 a 555 oscillator timer IC2 a 7400 quad 2 input NAND gate IC3 4553B 3 digit BCD counter IC4 a 7447 BCD to 7
268. r home that are aot wired for calAe Videos Bituriaia wee ees to any room eve 1 if someone is watching TV in the room that the VCR ts n Satellite pregrams BAe Iii programs throag out your hom without stringing miles of cable everywaere Live video Pi ULAR EE au film them or terre your camcorder into Network programs Rii raain TV i hooked up to in antenna you can broad cast its clear igual to all the o hers Recoton s video broadcasting system clones the aacessories cabk satellite VCR etc of cne TV and broadcasts it to any other TV ir your home wihout wires won t have to You can even watch one program on your main TV while someone else watches something different on another TV It s just like having a per home and it s legal in every State Hi tech home broadeast Recently the Federal Communications Commission allocated a band of radio frequencies specifically for wire less in 1r0me product applications Recoton took advantage of the FCC ruling by creating and introducing wireless equipment that can transmit within the prescribed frequency over distances of up to 150 feet One transmitter un limited receivers One transmitter will operate an unlimited number of receivers This means that a transmitter in the den can send signals to a TV in the living room kitchen bedroom and anywhere else you may have a TV Reco ton puts your favorite programs where you want them mos
269. r metal enclosure 16 to 48 inch length of inch PVC pipe 3 to 41 inch length of 34 inch PVC pipe 3 inch PVC couplings 4 to inch PVC reducer bushing 4 1 inch washer 3 g 24 Hex nuts PVC cement wire solder hardware etc Note The following items are available from North Country Radio PO Box 53 Wykagyl Station New Rochelle NY 10804 A complete kit of parts minus the wall transformer for the 100 kHz 30 MHz Active Antenna for 19 50 plus 4 50 S H The plastic parts pipe and fittings are not includ ed in the kit to reduce shipping costs A suitable wall transformer is avail able for USD 9 50 plus 1 00 S H NY residents add 8 25 sales tax A catalog of kits for amateur radio pro jects ATV transmitters downconvert ers receiver and video accessory Kits video and surveillance cameras and lenses is available for 2 refundabie with first order plus SASE with 0 75 postage and handling from the above address AM auto radio If not check alll wiring and the cables and con nections to T1 If reception is noisy try another location as indoor loca tions are usually noisy Next try the antenna on shortwave signals Adjust R5 for best performance Use R5 s default setting at first and if the setting seems OK or doesn t seem to matter then it is best to keep it You may want to experi ment with R5 s setting for various reception conditions for a time before deciding Use as low a gain setting as
270. r the sum frequency is sometimes used and is therefore called an upconverter The detection process depends on the type of signal being received If the signal is frequency modulated FM then a frequency or phase sensitive detector is used If the RF signal f4 is amplitude modulated AM on the other hand an enve lope detector is required And if the RF input is a CW Morse code or single sideband SSB signal then a product detector is used A prod uct detector is very similar to the front end of the superhet radio see Fig 1 except that f is replaced with the IF signal called f3 and the local oscillator is replaced with a beat frequency oscillator BFO that operates at a frequency f9 that is very close to the IF signal The frequency selective filter at the output is a low pass audio filter if the signal is an SSB signal then the BFO frequency f2 must be about 1 8 kHz from the IF frequency i e fy fy 1 8 kHz When those fre quencies are heterodyned together then the audio passband of the original SSB input signal is the difference signal CW signals which are on off telegraphy but are not otherwise modulated are also dif ference signals In order to demodulate those soiuosjoa y sejndoy 76614 snbny i Popular Electronics August 1997 da signals it s necessary to use a BFO operating at 300 to 2000 Hz from the IF signal so the difference fre quency wil be 300 Hz to 2
271. r Electronics August 1997 RO RO it then the WebTV interface is perfect And you might even be happy using just the remote control because WebTV is designed just for that Because of that there is some adjustment needed if you re coming to WebTV from the PC side We ll admit that it was difficult to get ourselves in the position to objectively evaluate WebTV because we are used to full time Internet access over the corpo rate LAN local area network At home we were inclined to stay away from online activities just because the response time became unbearable Even with our jaded outlook however WebTV lived up to its promise Its modem is fast and its basic menu system lets you wander in interesting yet unde fined and unrestricted ways The system is designed to deliver Web content speed ily which is probably a good thing After all even the most sedate couch potato is used to seeing a pretty good multimedia experience every time he turns on the TV The relatively static Web can t hope to compete WebTV Networks has some interesting tricks up its sleeves regarding video delivery but more on that later WebTV has one major disadvantage It uses a TV set as a display device For text delivery the TV doesn t present a prob lem because WebTV uses a font that is easily readable However for graphics or text that is presented in a graphic the TV can be a hindrance A good example is the Popular Electroni
272. r U S and Canadian DXers have reported hearing the station It has a variety of musical programming from blues to heavy metal until sign off just after 2200 UTC Reception reports are welcomed Tosun told me You can send them a letter although the mail which must be forwarded to the TRNC via Turkey is slow The address is Bayrak nter national Bayrak Radio and Television Ataturk Square PO Box 417 Lefkosa via Mersin 10 Turkey A faster way is via e mail brt cc emu edu tr And if you want to plug in to BRT s Internet Web site try www cc emu edu tr press brv bort htm Web Radio lve talked in previous columns about using your computer as a tool to assist your shortwave listening The paragraph above is one example of that Now its possible to listen to for eign and domestic stations on your computer so1u0sjoe a weindog 2661 IsNiny ol Popular Electronics August 1997 Passport To World Band R the longtime annual guide to SW listening has come out with a new publication called Passport To Web Radio which spells out this new form of DXing in detail Internet users can now hear the hometowns of America and the world through the magic of Web Radio says Larry Magne editor and publisher There s a global bazaar of FM AM and other stations and networks wait ing to be explored over the Web Those Web stations started appearing about a year ago but
273. r own pace and professionals UCANDO videos to be a valuable Z source of reference material if videos aren t learning tools you ve ever seen return them within 30 days for a complete refund These videos are being used by Tech Schools CET s Military Branches Ham Operators Industries and more across the round the world Order today and see how UCANDO Ss AMRadio FM or mail check or money order to 1 800 678 6113 Greenville OH 45331 FREE Shipping FREE Catalog CIRCLE 136 ON FREE INFORMATION CARD SURVEILLANCE The Latest High Tech Professional Electronic Devices Our latest catalog offers a HUGE selection of surveillance counter surveillance privacy devices hidden video equipment pinhole camera w audio 159 electronic kits telephone recording systems 7 Hour 125 16 Hour 199 touch tone decoders scanners bug phone tap detectors voice disguisers telephone scramblers locksmithing tools and more Catalog 5 00 SPY OUTLET P O Box 337 Buffalo NY 14226 716 691 3476 716 695 8660 a ELECTRONICS WORKat HOME art time Full time up 35 hour 4st Publishedl Home Based Electronics Businesses Comprehensive GuideBook reveals secrets to using technical skills to make big money NOW 250 pages of insider info amp sources Be your own boss amp gel out of the rat race NOW Send 24 FRE IN A Canadians add 2 OCP Enterprises PETER AT WE come
274. r shunted between pins 1 and 8 of the LM386 Cy in Fig 9 If Cy is not used then the circuit will have a gain of about 20 but if a 10 F capacitor is used the gain will be about 200 Conclusion Direct conversion autodyne receivers are easy to build and work well They are par ticularly suited to experimenter and hobbyist use and they will provide results that will surprise you z S31u01 23 3 seiINdog Z664 IsNnbny Popular Electronics August 1997 J o COMPUTERS ARE HELPING Continued from page 47 IN operation sound is picked up by the external microphone in the user s headpiece placed adjacent to the implanted receiver The sound is then carried down the cable to the speech processor Using sophisticated software with customized digital and analog pro cessing strategies the processor converts the sound into an electri cal signal that is returned through the same cable back to the head piece A small transmitter in the headpiece sends the signal across the skin via radio waves to the implanted receiver The signal then travels to the electrode array in the inner ear bypassing damaged parts of the auditory system and directly stimulating the auditory nerve Finally the auditory nerve carries the electrical signal to the brain to be interpreted as sound The CLARION system underwent several years of clinical trials with patients ranging in age from two year old children to 80 year olds who have been pro
275. reflector and hear blocks away The BIG EAR can be hidden about anywhere Makes an ultra sensi tive intercom Can be used as a 1 5W AMP We supply a mini electret mike in the kit Power requirement 6 to12v DC SIZE 1 75 x 1 AA 1 BUILT 29 95 KIT 10 95 ge TRANSMITTER W Small but mighty it fits any sa where Phone line powered never needs batteries Transmits both sides of a phone conversation loud and clear wireless to any FM radio at great distances Variable tunes from 7ZOMHz to 130MHz FM You can also use it as a speaker phone SIZE 1 25 x 6 TEL B1 KIT 12 95 Panett aletetere lo 3 WIRELESS b FM MICROPHONE Small but mighty this little jewel will out perform most units many times its price It really stomps out a sig mal nal The WM 2 kit is a buffered wireless mike that operates from 80MHz to 120MHz FM the frequency of any broadcast FM radio Includes a mini electret mike 6 to 12v DC SIZE 1 25 x 1 WM 2 KIT 14 95 TA MasterCard PANE VISA S91U021 98 3 seindog 7664 Isniny co Popular Electronics August 1997 amp SMALLEST Wireless Video Transmitters Used by hundreds of hobbyists and professionals alike in R C models Robots Surveillance Video movie Special Effects and Law Enforcement previously used expensive
276. rience or electronics back ground is necessary Just average mechanical aptitude and the ability to follow simple A B C repair pro cedures that are clearly outlined for you And when you complete the course you will receive Foley 30 DAY NO RISK TRIAL Send for details Send coupon today for FREE Fact Kit No obligation Don t miss out on this once in a lifetime opportunity Send in the coupen NOW Get aff the facts and study them in the privacy of your own home There s absolutely no obligation and no salesman will call on you So don t delay Mail the coupon today MAIL TODAY FOR FREE INFORMATION PACKAGE Foley Bel Institut FOLEY Kansas City MO 64120 1395 YES Without obligation send wee information kit so can learn how to become a professional Satetlite Dish TW Electronics Specialist in order to earn high extra income Dept 31445 _ VCR Repair Untimmited profits in this growing field Dept 62673 L interested in an exciting money making career in Computer Repair Maintenance and Upgrade Dept 64572 _ Personal Computer Programming Learn fast at low cost for big earnings Since 1926 __ State Zip City l Call toll free 1 800 487 2100 s31Uu01499 3 eiNndog Z664 Isnony BEST DEALER PRICING CABLE ELECTRONIC COMPONENTS EQUIPME Direct e K i uN dip DIRECT ilp oo0 s 4 nan a ee ee D CONVERTERS FILTERS i tor
277. rit II begins to scramble radar sig nals as far as three miles away from the speed trap Its range of effectiveness extends to almost 100 feet away from the police car at which point you should be able to make visu al contact and reduce your speed accordingly Encourage responsible driving While the Spirit Il is designed to help you and me avoid speed traps it is not intended to condone excessive speeding For that rea _ son there is an optional one year Ticket Rebate Program for just 19 95 the manufacturer will pay tickets where the speed limit was not exceeded by more than 39 or 15 miles per hour whichever is less Double protection from speed traps Radar isn t the only weapon the police use in their revenue generating speed traps The latest weapon in their arsenal is the Lidar gun To counter the latest threat Rocky Mountain Radar created the Phazer Like the Spirit H the Phazer also scrambles laser in a similar manner as the radar scrambler It uses light emitting diodes LEDs to fire invisible infrared pulses It confuses the computer inside the laser gun by giving false indica tion of the car s distance blocking measure ment of your speed It includes the exclu sive Ticket Rebate Program Triple your protection against speed traps lf either the Spirit IT or the Phazer sounds good but you prefer to be notified when you are in range of a police radar
278. ritron owned by the popular MFJ Enterprises Inc announced their model AL 800H Linear Amplifier for the high frequency HF ham bands see Figure 1 The output power is rated at what Ameritron calls 1 500 watts plus The list price is 2 295 which given the price of everything else these days isn t too terribly bad for a major hobby item photography fans would scoff at that price and you know what mean if you ve ever priced lenses and accessories for cameras that take 120 or 220 size film There ee eS D i eta piace ms ee T F 4 a a ai n i e Ta wt ee j p 0 im mar N 7 ay AR A a a S 1 a L a Pi gim JOSEPH J CARR tubes are pricey automatic load con tro ALC and ball bearing vernier re duction drives for tuning and loading The tuned input circuit uses adjustable slug tuned coils which is common prac tice on HF linear amplifiers The output Fig 1 The Ameritron AL 800 Linear Amplifier has a rated output of 1250 watts PEP Its big brother the AL 800H uses two Eimac 3CX800A7 tubes to smash through the tono sphere with over 1500 watts are actually two models of the AL 800 amplifier The straight AL 800 which lists at 1595 uses a single Eimac 3CX800A7 power amplifier tube and runs up to 1 250 watts peak envelope power PEP The addition of the H suffix to make the mode number AL 800H means that the amplifier uses a pair of Eimac 3CX800A7 power a
279. riving preventing police ates e rena from measuring W S MY Cruise con trol set at eight miles your speed over the limit I catch a glimpse of a police car parked on the side of the road My heart skips a beat and for some reason l look at my speedometer After I have passed the trap my eyes stay glued to my rear view mirror praying the police officer will pass me up for a bigger fish It seems that as speed detection technolo gy has gotten more and more advanced speeding tickets have become virtually unavoidable And although devices exist that enable motorists to detect these speed traps they are outlawed in many states including mine The solution Today Rocky Mountain Radar offers drivers like me a perfect solu tion the Spirit II Utilizing a passive radar scrambler The Spirit H makes your automobile electronically invisible to police speed detecting equipment The radar scrambler works by mixing an X K or Ka radar signal with an FM chirp and bouncing it back at the squad car by way of a waveguide antenna effectively confusing the computer inside the radar gun Perfectly legal Some radar devices have been outlawed because they transmit scrambling radar beams back to the waiting law enforce ment vehicle The Spirit Il however reflects a portion of the signal plus an added FM sig nal back to the police car This in effect gives Scrambles Radar Reflected radar with an FM
280. rne aerate aria meee 4 Danin ahe a e aae r e eae AA eana o eai ma a A a ean a enaa ae Paa i pa ea ee handling the apartment or call the number given at the top of the listing Some offices let you get a head start by filling out an online credit applica tion Either way you go about it the process is made as simple as can be For those who need a short term place to live Temporary Furnished Suites is the link to select While not as interactive as the part of Rent Net we just described the Furnished Suites section provides you with links to com panies that specialize in finding tem porary places to live in particular areas So if you pick New York for example you ll be able to fill out an e mail form that describes what you re looking for in a place You can also call a company to see what they have available Selecting International Rentals involves a similar process Except here you pick a country and then choose from different types of ser vices For example there s a chain called Apartment Hotels that lets you rent with a minimum of one night only There are also some non rental links such as a resource for traveling in Europe by train Self Storage Facilities links you to companies in each state that provide you with lockup storage should also point out that throughout all the main sections of Rent Net you will find ads that link you to assorted relocation related services including rental truck agencies and
281. ronic board games that you can build from the plans in this book Whether you are interested in motor racing searching for buried treasure on a barren island of for gold in Fort Knox spinning the whd l of fortune or doing a musical quiz there is something for you to build and enjoy BP351 WordPerfect 6 Explained 6 95 This is a practical hands on book and the routines described will help you get the most out of WordPerfect 6 The book explains the hard ware requirements for the package and steps you through a standard installation It guides you through the WordPerfect program environment to enter edit and enhance text and shows how to get the best from the three different operating modes depending on the type of PC you are using The formatting codes button bars ribbon tabs graphic manipulation and Styles will no longer be a mystery ee Not Personalize Your PC 6 95 Find out how to Set up and organize groups of programs and data files and change the opening logo use the Control Panel to Personalize your working environment use screen savers and wallpaper files manage the DOS prompt and transfer your customization files to a new Windows installation In DOS you discover how to Write batch files and create Specialist programs using the debug program design professional looking menus and more ELECTRONIC TECHNOLOGY TODAY INC P O BOX 240 Massapequa NY 11762 024
282. rrjj aol com a This n That et s start off with an interesting let ter from David Booth Usually let ters appearing in this column are shortened or paraphrased in order to conserve room However Dave s letter is so packed with lore on early Westing house RCA production that I ve decid ed to run it in its entirety Which Was the Senior Aeriola was recently rereading the October 1989 issue of Popular Elec tronics save all my back issues and noted that you responded to a Mr Ray Shetrone concerning an Aeriola or Radiola Senior which was missing the inside card from the lid My grandtather James D Booth who died in 1970 worked for Westinghouse from 1919 to 1962 He said in his 1962 retirement speech quoted below that the Aeriola Senior was produced in the L 80 sec tion of Springfield Works Later in 1921 we moved into larger quarters known as L 80 There we built RC receivers and that little marvel of the age the Type LV Vocarola I ll have to skip lightly over the Aeriola Senior Type RF which was actually produced a little before the Aeriola Junior Type RE The Aerioia my italics Type RS was really a very good receiver when used with headphones Davenport Iowa came in loud and strong In 1922 radio suddenly became big business and cost reduction hit the fan Cabinets were the most costly item so we built samples of the Aeriola Junior in tomato cans RCA wouldn t g
283. rs 8 0 0 8 1 1 gt 5 2 0 3 pots inductors test equipment breadboard ina supplies PC supplies industrial computers 602 464 2485 Paua et ME r iee parsonck CETP 6 0 2 4 6 4 gt 5 8 2 4 FA X ers and computer parts plus much much more FAX us your name and address or call 800 811 5203 ext 5 to leave a Message ON Our catalog request line F j WE ACCEPT Cc ae S91u0149913 seindog 2661 Isnbny Popular Electronics August 1997 wo N WRK KKK KKK 1 800 344 4465 CIRCLE 147 ON FREE INFORMATION CARD WE HAVE IT ALL Surveillance Infinity Transmitters FM Wireless Transmitter Kits Vehicle Tracking Systems Bug Detectors Caller I D Telephone Register with Printer Long play Recorders Wired Mikes Shotgun Mikes Telephone Recording Adapters Aicohol Testers Drug Testers Telephone Scramblers Hidden Video Cameras Telephone Tap Detectors MUCH MUCH MUCH MORE Our 27th Year Small catalog FREE Larger catalog send 5 Mail Order only Visa MasterCard and C O D accepted for equipment only Inquire for dealers prices A M C SALES INC 193 Vaquero Dr Boulder CO 80303 Mon Fri 8 a m 5 p m Mtn Time 800 926 2488 Why rent your nth t cable box 4 i You can buy your own 3 for as little as 4 K _ If you are not getting y Pi this catalog you are missing Out On some k B of the best
284. s Kit Corner EE aum Model M 6100 ___ over 100 kits available g Programmable DMM PT 223K 4 p Fiber Optics Includes FREE Computer Interface 45 95 Technology and FREE Software Analog Bar Graph Phone kit with tralning course e Large 3 3 4 LCD Display si Model FO 30K e Menu Driven train 1 9 95 z ing e Triple Display Model AM FM 108K course RS 232 Interface Transistor Radio Kit e True RMS 9 Basic Functions including cap amp freq with training course 29 z amp Transistor Test e Auto Power Off WE WILL NOT BE UNDERSOLD C amp S SALES INC e Easy to use 15 DAY MONEY BACK GUARANTEE UPS SHIPPING 48 STATES 5 150 W CARPENTER AVENUE es WHEELING IL 60090 SS FULL FACTORY WARRANTY OTHERS CALL FOR DETAILS FAX 847 541 9904 847 541 0710 Tan IL Residents add 8 Sales Tax http www elenco com cs_sales CIRCLE 32 ON FREE INFORMATION CARD 39 11 functions inciuding freq to 20MHz cap to 20uF Meets UL 1244 safety specs 99 95 7 Functions with data hold Compares to Fluke Model 771i i a M 1005K Compact Multimeter 49 25 6 Functions PRICES SUBJECT TO CHANGE WITHOUT NOTICE FREE PROBES QSCILLOSCOPES i Free co Pace SCOPES Lowest Prices of the Year E Sa re B amp K Precision Scopes 60MHz ANALOG WITH DIGITAL STORAGE ec and readou Model 2560 A8232 por
285. s weicome 30 arrea ORMANCE ELE NICS Free catalogi PROF INC 1 815 1512 CABLE TV descramblers converters Quantity discounts 30 day free trial Competitive rices Call now 1 800 322 0921 REGAL SALES INC CABLE TV descramblers One piece units Pio neer 6310 s Scientific Atlanta s DPV7 s and others Lowest prices Money back guarantee Houston TX 713 691 4610 CABLE test chips Jerrold Pioneer Tocom Sci entific Atlanta Zenith Jerrold cubes Pioneer pro grammable cubes HUDSON 1 800 863 3237 WE carry all Regal models RR 92 RC 83 550 MHz 99 Ch DQN7 550 MHz 99 Ch OAK Micro 550 MHz 99 Ch BC 4535 550 MHz 86 Ch SA 3529 550 MHz 99 Ch SA 8540 550 MHz with Vol Crt 99 Ch DRZ DIC DP 5 DPV 5 Pioneer 5135 amp Zenith 1086 Dealers are welcome Please call us for the latest price Or visit us at our web site http www vntechnology com MASTER files test modules amp cable boxes for all types of CATV converter units 909 941 4858 CONFUSED Descramblers Will explain all your options all makes and models Wholesale and re tail Open 6 days wk 9AM 8 PM Est Best tech support and friendly service Toll free 1 800 238 0967 ROYAL ENGINEERING INC SMART Phoenix The most advanced cable ANC ERCI Jerrold compatible only MAKFIT RESEARCH 1 800 220 3543 ALL chips 9 00 18 00 Security bits from 9 95 converters filters Lowest price guarantee Any time 1 800 760
286. segment decoder driver IC5 a 4060 14 stage ripple binary counter divider ICO a 7415393 dual 4 bit binary counter four FND507 common anode seven segment displays DISP1 DISP4 and a handful of support components In the DIMF Frequency Counter IC5 s built in oscillator which re quires only a crystal plus a few resis tors and capacitors is set to Oper ate at 32 678 Hz The oscillator fre quency is internally divided by its built in Counter circuitry The output of IC5 at pin 1 is fed to the clock input of IC a half of the 7418393 dual 4 bit binary counter at pin 13 The output of IC a at pin 8 divides along two paths In the first path the output signal is fed to IC2 a at pin 12 and used to trigger gate the NAND gate In the other path the signal is applied to C5 a 0 005 pF capaci tor transforming the leading edge of the squarewave output to a very fast positive going spike The spike is applied to the reset terminals of IC3 and IC b causing them to reset just before the count begins IC6 b which functions as both a count 1000 latch and an overrange detector counting overflow puls es is used to illuminate the thou sands display DISP4 On the first overflow pulse Count 1000 pin 3 of IC b goes high PL1 T1 D3 117VAC 1 2A c t 12y 1N4001 causing four segments a d e and f of DISP4 to go dark Pin 5 of IC6 b is at ground potential causing seg ments a an
287. t Unlimited choices Since the broadcasting in 900 MHz frequency signals there is no time consuming oF complicated wiring The receiver can be easily moved from one television to another The transmitter will also broadcast to mul tiple receivers so you can watch the same program on multiple TVs simultaneously The transmitter con nects to the source TV the receivers simply connect to the others sonal broadcasting system in your system uses the latest Satellite in bedroom VCR in guest room Exclusive factory direct offer With this breakthrough in home video broadcasting tech nology you can have the convenience of your own personal wire less broadcasting system for a frac tion of the cost of owning your own TV station For a limited time only we are offering Recoton s wireless video broadcastng system one trans mitter and one re ceiver for the low price of 99 You can order addition al receivers for ath er TVs for just 59 each Risk free offer The wireless video broadcasting sys tem by Recoton is backed by Com trad s exclusive risk free home trial Try it and if you are not completely satisfied simply return it within 30 days for a full No Questions Asked refund It also comes with a 90 day manufacturer s limited warranty Most orders are processed within 72 hours and shipped UPS ADD A TV TOWER but without the expense For just 99 the Rec
288. te well into the shortwave region is shown here The output of the VFO is fed to a buffer amplifier built around an MFE 02 JFET Q2 that is used to isolate the oscillator from the following stage the desired frequency coverage The NTE catalog and other sources offer versions with values ranging from 11 to 440 pF Outboard Circuits Thus far the cir cuits that we ve discussed are cen tered around the direct conversion process In this section we ll present a couple of circuits that can be used to augment the converter including a_variable frequency oscillator VFO and high gain audio amplifier Figure 8 shows a VFO circuit that can operate well into the shortwave region 20 MHz or so The actual oscillator circuit is built around a 40673 dual gate MOSFET QI which can be replaced by an NTE222 Tuning is accomplished by way of coil LI plus the combined capacitance of C1 main tuning C2 trimmer tun ing or bandspread and the optional capacitor Cy which is used to provide the balance of the required capacitance Because LI is tapped the circuit is a Hartley oscillator As in the previous case the tap is about 25 percent above the ground end of the coil At the output of the VFO is a buffer amplifier built around JFET Q2 an MPF102 or NTE312 that is used to provide isolation to the oscillator circuit Unbuffered oscillators tend to pull i e change output fre quency when the load impedance changes
289. ted for space based applications where small rugged and reliable radiation sources are critical A LASSOR mounted on a satellite could be used for instance to cool infrared cameras and super conducting relays since the cryo cooler would have no moving parts its lifetime would be limited only by the longevity of the diode lasers Current commercial diode lasers have mean failure times of approximately 14 months The researchers believe cryo cooler life times could be extended by com bining multiple redundant low power diode lasers effectively dis tributing the heat load To achieve a 10 year lifetime the cryo system would require eight sets of diodes Ultimately lasers could find their way into desk top computers enabling superconducting circuits to operate at speeds hundreds of times faster than current conventional electronic components The optical refrigeration process has received a patent The next step is to attract industrial partners Further information on the LASSOR is available on the World Wide Web at http labs3 lanl gov i ANTIQUE RADIO CLASSIFIED Free Sample SiR Antique Li fat a AULA E Z8 Largest Circulation Monthly J o Articles Ads amp Classifieds 6 Month Trial 18 95 1 Yr 38 95 ee Iet Class A R C P O Box 802 L18 Cart sle MA 01741 HALL EFFECT COMPASS Continued from page 38 polarity is correct reverse polarity will do
290. termg text via an on screen keyboard manspulated by a handheld remote is cumbersome to use a polite phrase So plan on adding another 69 to get the wireless infrared keyboard It is possible we shouid point out to use a standard IBM compatible keyboard mini DIN plug with the WebTV terminal but normal TV viewing distances make that an inconvenient solu tion at best WebTV is not only an Internet service provider ISP but also an online service itself much like America Online or CompuServe When the box is turned on it automatically connects to a WebTV main page The main page is designed to allow users to surf the Web using only the remote control New users will probably ie a a find it to be pretty good Experienced Internet users won t they ll just want to get to where they re going But they can do that easily enough by choosing option and go to Launch WebTV by pressing the POWER button on the remote keyboard and you re greeted by a city skyline accompanied by some suitably hip music as the units modem connects to the WebTV network The modem is fast 33 6 kilobits per second Kbps and the WebTV s basic menu is inviting offering icons for mail favorites otherwise known as bookmarks explore search sports news and more If you re interested in just browsing the Web or surfing as many people call soiu0soe 4 Jeindog 7664 Isnbny N Popula
291. ternet content in an easy to use menu system For example when first launched the ser vice provides icons for Mail Favorites Explore Search Around Town Sports News Briefs and a highlighted WebTV content provider Clicking any of the icons brings up submenus making it pos sible to find interesting things with just a few clicks of the remote control One of our first stops was Around Town and we selected area restaurants from the submenu that was presented Instead of seeing information on local Long Island restaurants we were present ed with restaurants in New York City about 40 miles away We had better luck looking for local movie listings which was able to show us the selections for the five theaters closest to our home The Explore icon makes surfing with the remote palatable Click it and you re presented with a host of options including Arts and Books Community Education Entertainment Kid s Club Lifestyle and Science and Technology Click on any of those and you re presented with other options for example Newsstand to get you where you want to go even if you didn t know you wanted to go there when you started You can easily move from link to link with the remote control WebTV is more of a link based browser than a standard PC running say Netscape Navigator Four cursor keys on the remote control are used to highlight links They surround a central GO button that selects the link Image m
292. test points for TouchTone coded for secure operation Works with any 400 550MHz scanner radio quick and Uning Stop burglars and intruders Gain 6 dB typical Has built in microphone Transmit shone A medioa Reliable 24 hour protection Noise figure 3 dB typical Easy to use t to most any FM stereo receiver ee ee ee Serving the public since 1981 E NANDI rea re 1270 E Broadway Rd 113 Tempe AZ 85282 WE ACCEPT CHECK VISA MC MO COD SEND MAIL ORDERS TO XANDI ELECTRONICS INC SHIPPING amp HANDLING EXTRA X X 25647 oy VM Me 0 04011 8 1107 17 elem TEMPE AZ 85285 5647 s21u01 29 3 seindod Z664 isnbny CIRCLE 134 ON FREE INFORMATION CARD a wo Popular Electronics August 1997 Our Complete Catalog is Ry now a online Don t let the price fool you This meter is a i switch HP 9150 Scope Probe SetDC 150MHz 24 95 21 9 9 Check Out S Si 101 What RK SOET We INC Have Y To Offer k Fantastic DMM Offer digital multimeter designed for engineers and hobbyists Equipped with 5 functions and 19ranges Each test positionis quickly and easily selected with asimple turn of the FUNCTION RANGE selector rotary Ganeral Rubber Boot Included Our Display 3 1 2 Digit LCD 21mm Figure Helght Best with Automatic Polarity O ffe r Overrange Indication 3 Least Significant Ever Digits Blank Temperature for Guarante
293. the 9VOLT IN OUT Fig 3 With this compact voltage regulator you can power the mini stereo power amp from your auto battery A l x 2 inch metal heatsink will keep this regulator cool speakers or headphone through capacitors C11 and C24 Switch S1 is a power on off switch while switch S2 lets you choose between the speakers and headphones Switch S3 is a stereo monaural switch Closing this switch produces a monaural output while opening it selects stereo sound The circuit can be powered by a 9 to 12 volt DC adapter For operation in a car use the simple three terminal posi tive voltage regulator circuit shown in Fig 3 which sets the DC output for the amplifier at 9 volts R3 7 5K R11 250K VOLUME STEREO 1 MEG BALANCE C3 R7 A7 680 SEE TEXT Your CD player s output power must be sufficient to prevent loss of high frequency signals Just to show how small the whole amplifier is have assembled the circuit on a 2 x 3 34 inch circuit board All parts are available from Digi Key or local parts distributors Jose Ignatius A Alea Philippines I m really surprised that this unit can be built so small The car voltage reg ulator is a really nice touch Note builders can dispense with switch S2 by using a headphone jack that cuts the signal to the speakers when a plug is present Cebu Stereo Power Amplifier if you want an amplifier that pro duces more au
294. the number jumped last autumn when RealAudio s improved software came out About 400 Web Radio outlets are available now Programming may be local nation al or international Unlike SW stations with scheduled programming some Web Radio services are on demand when you visit their Web sites London s Independent Radio News for example offers a periodic IRN newscast when you request it Other sites offer live broadcasts Do you want to hear play by play Japa nese baseball You can hear the Tokyo Carps broadcasts in Japanese of course on JOER RCC R 1350 Hiro shima via Web Radio Says Magne An enormous plus of Web Radio is that while you re listen ing you can continue using your com puter just as you always have ie word processing e mail surfing the Web The stations and software are free too So if your PC is hooked to the Internet and handles sound then Web radio costs little or nothing Magne says that there are at least 50 countries you can hear on Web Radio at this writing His new book Passport To Web Radio includes information on how to get started and what s on and worth listening to It is available at many book stores For more information try Passport s own Web site WWW pass port com or call 215 794 8252 FBIS Saved scientists researchers and others who for years have relied upon the reg ular reports of the Foreign Broadcast Information Service FBIS for years were u
295. ther alternative is to use a tuned transformer intend ed for IF amplifier service in radios The 455 kHz transformers in AM radios can be used for VLF and AM broadcast band applications while those from FM broadcast radios 10 7 MHz can be used for shortwave receivers The best ones are those that have the resonating capacitor in a small hollow space on the bottom of the transformer Those capacitors can be crushed to remove them from the circuit The power for the NE602 double balanced mixer is provided by a 5 volt DC power supply The NE602 wants to see a lower voltage less than 8 volts DC than many popu lar ICs so if you need to use a high er voltage such as 9 or 12 volts then include a low power voltage regulator in the circuit to drop the voltage to the desired range For example a 78L05 which is housed in a small plastic transistor pack age will work nicely some people have used a lk resistor for R2 when using the NE602 in 9 volt battery operated circuits In other cases people have used a lk resistor for R2 and a 68 volt Zener diode shunted by a 0 1 pF capacitor at the power supply ter minal pin 8 of the NE602 The local oscillator signal is applied through a 0 047 uF DC blocking capacitor C4 to pin 6 of ICl The signal level should be approximately 700 millivolts peak AUDIO TRANSFORMER to peak mV p p at a frequency close to the RF see rules above The output signal taken fro
296. time bang Signal delay time V mode displays 2 signals unre lated in frequency 4 OSCILLOSCOPE SELECTION CHART ANALOG Model Bandwidth Sensitivity No of Sweep Rate Delayed Video Component Beam Time a Component lester Z axis input MHz max Channels Max ns div Sweep Sync Tester Find Base Single sweep S 126C 60 imvV div 2 10ns div Yes Yes Yes Yes 2 1 225 S 134 40 1mV div 2 10ns div Yes Yes Yes Yes 2 S 134C 40 1mV div 2 10ns div No Yes No No 1 20MHz DUAL TRACE S 1330 25 ImvVidiv 2 10ns div Yes Yes Yes Yes 2 Model 2120 2 Year Warranty 1325 25 1mV div 2 10ns div No Yes No No 1 Special 389 95 DIGITAL STORAGE Model 2125 with delayed sweep Model Bandwidth Analog No of Sampling Memory Internall Pretrigger Output 539 95 MHz Sen max Channeis Rate Channel Backed Up ImVidivision sensitivity DS 303 30 imvidiv 2 20MS S 2K Yes 0 25 50 75 RS232 Er Brel pee D e pos 60 1mV div 2 20MS S 2K Yes 0 25 50 75 RS232 Calibrated 19 step time basea with x10 magrufier Compact low profile design _ AT PRICES THIS LOW THEY LL BE GONE gt F Affordable Spectrum j HITACHI SCOPES K Analvzers by B amp K Inventory Reduction Sale y y Lowest Prices of the Decade 1 05GHz Series V 209 20MH2 Battery Operated V 695 60MHz w Cursors Model 2625 2395 Was 1505 NOW 1095 Save 410 Was 1815 NOW 1395 Save 420 Model
297. to keep track of all the area volume figures that the ProMeasure has determined Actually we also ended up carrying around a traditional calculator as well as a pad pencil and the ProMeasure We found the ProMeasure s conversion calculator to be too small and mushy for comfortable accurate use We pre ferred using our old familiar pocket cal culator to add up the long list of wall and ceiling areas we d obtained with the ProMeasure s measurement computer Because we d be using different paint colors in the various rooms we obtained and jotted down subtotals for each room then added those to the entire wall ceiling area to be primed and painted a whop ping 3881 59 square feet It was at that point that we seriously considered hiring a professional painter Then we remem bered our diminished finances and brave ly pressed PAINT We learned that we 4 The ProMeasure uses ultrasonic waves to measure distances would need 11 50 gallons of primer to do one coat throughout Because we d written down the subto tals for each room it was then easy to determine how much flat white paint we d need for the hallway kid s rooms and all the ceilings how much opal we d need for the master bedroom walk in closet and office and how much moisture resis tant white we d need for the bathroom We still didn t have a clue as to how much white semi gloss would be needed for the doors and trim
298. to understand terms it helps you understand how antennas work the advantages of different anten na types and how to get the best performance out of an antenna Bea Electric Design Data 7 95 A builder s bargain book a comprehensive ready reference manual for electronic enthusiasts with over 150 practical circuits It covers the main kinds of com ponents trom pig tail leads to surface mount pin outs specs and type selection Basic units are detined and most used formulae explained Five additional sec tlons are devoted to circuit design covering analog digital display radio and power supply circuits Fee MS DOS Work For You 6 50 This book could help you improve your system Set up and provide you with a simple to use but pro fessional looking menu system The routines described will help you understand more of the work ings of MS DOS and help you get the most out of your computer in terms of efficiency Productivity and enjoyment BP341 MS DOS 6 Explained 7 95 The book covers How the DOS operating system of your computer is structured so that you can understand what happens when you first switch on your comput er How directories and subdirectories can be employed to structure your hard disk for maximum efficiency how to use the DOS Shell program and much much more
299. trations wouldn t have to be repeated in three separate sec tions The result is confusing to the eye and requires three times the page turning on the part of the user The remote control is chock full of but tons Centered in the upper portion of the remote is a tiny joystick style control which also serves as a SELECT button The joystick is ringed by four buttons TITLE MENU and two skiP buttons Between the SKIP buttons is the RETURN key Rounding out the top portion are STOP and PLAY but tons At its top are POWER and OPEN CLOSE buttons The remote control s midsection contains a numeric keypad along with a host of buttons for operating DVD func tions modes and setup The bottom por tion of the remote features POWER and channel and volume up down buttons that can be programmed using the two digit TV manufacturer codes supplied in the manual to operate your TV s basic func tions For the most part though you ll be using the joystick and the buttons that surround it To use any of the on screen menus you pull or push the joystick to move up and down through the lists of options and then press it to select your choice If the options are numbered you can also use the numeric keypad to indi cate your choice To pause the video and get a still pic ture tilt the joystick up Still images remain clear unlike paused frames of videotape When in still picture mode tilting the joystick up again advances the
300. ts 3 1 2 Digits Maximum Display 19999 counts 4 1 2 Digits w Automatic Polarity Indication w Automatic Polarity e pH Meter e LUX Meter Indication Method PM 128 LCD Display Indication e dB Meter e LCR Meter PM 129 LED Display Indication Method LCD Display e Watt Meter e Other Industrial Measuring Method IG Conve pay sire er ae Indication 1 Shown in the Display e Current Meter amp Domestic Uses or sysiem nput Impedance gt 100 Mohm i Overrange Indication 1 Shown in the Display A 0 5 C lt 80 _PM 128 3 1 2D LCD Digital Panel Meter Reading Rate Time 2 3 ROGAN par tac ASCO eA Sie eee Input Impeda gt 100 Mohm Decimal Pol Selectab J PM 129 3 1 2D LED Digital Panel Meter miei impedance slates son en T Vologe VEC Features Power Dissipation PM 128 IMA DC Size 67mm x 44mm e 200mvV Full Scale Input Sensitivity eee at papal sg A S LO W A S 5 2 e PM 128 Single 9VDC Operation Hda W NS SUTER 3 e PM 129 Single 9VDC Operation Supply Vogga o enc evine 5 25 ea e Decimal Point Selectable Size 67mm x 44mm PRICE EACH e PM 128 13mm Figure Height CATNO DESCRIPTION l 10 25 100 250 e Automatic Polarity Indication PM 128 3 1 2 Digit LCD Panel Meter 9 90 7 09 6 40 5 586 5325 e Guaranteed Zero ReadingforOVoltinput PM 129 3 1 2 Digit LED Panel Meter 11 49 9 54 8 67 795 695 it LCD Panel Meter 19 88 16 40 14 90 13 66 11 93 High input Impedance gt 100Mohm PM 328 4 1 2 Di Ball Bearing 12V DC Fans Thes
301. ulated or bare bus wire After that install the Zener diode while paying close attention to its proper orientation Next move on to the resistors and ceramic capacitors followed by the elec trolytic unit Be sure to observe proper polarities when installing the electrolytic capacitor Install the voltage regulator IC3 again observing the proper polarity It may be necessary to bend the leads of IC3 to fit the printed circuit board With that done install a 24 pin IC socket in the board position reserved for IC2 Before continuing clean the foil side of the PC board with alcohol or flux remover Then install a 9 volt battery connector where indicat ed Be sure to attach the connec tor to the board with the polarity shown Install the 74HC 154 CMOS 4 to 16 line decoder C2 Since both IC and IC2 are CMOS devices they can be easily damaged by static discharge Take proper anti static precautions when handling those chips Refer again to Fig 3 before installing IC2 to make sure of the proper orientation of pin 1 then press the IC firmly into the 24 pin socket making sure that it is proper ly seated Install the 1490 sensor IC1 It may be necessary to bend the leads of the Hall effect compass slightly so that they fit into the holes on the PC board Note There is no absolute orientation of U1 It may be installed in any one of four rotat ed positions and will still work prop erly Fig 4 shows the label appro
302. ure for Measure PROMEASURE HOME CONTRAC TOR MODEL HC 1000 From Seiko Instruments USA Inc 2990 West Lomita Boulevard Torrance CA 90505 Tel 1 800 873 4508 Web http www seiko usa cpd com cpd Estimated street price under 50 We were rapidly approaching the end of a period of traumatic physical emotional and financial upheaval otherwise known as a major home remodeling project To accommodate our growing family not to mention all the home office space re quired for testing products and writing Gizmo we had been faced with the diffi cult choice of either moving to a larger house or adding on to our existing home After a few weekends spent roaming the town with realtors we d decided to take the plunge and convert our two bedroom one bath 1100 square foot Cape Cod into an 1850 square foot colonial style home with three bedrooms a large office a sec ond bath and a stand up attic Finally after weeks of noise dust con fusion and check writing the end was in sight The contractors promised to be completely finished by the end of the week What a relief it would be to actual ly be able to live in our palatial well at least in comparison new home Unfortunately moving day wasn t the following Saturday Our budget sim ply didn t allow us to hire painters or to have flooring professionally installed Working weekends and evenings we hoped to be furniture ready in another couple of weeks
303. uto placement tools You can also layout or edit circuit board artwork using SuperPCB s intuitive easy to learn editing features Buy With Confidence Our products come with a 30 day money back guarantee and free unlimited technical support Free Functional Demo You can obtain a free demo from the Internet at http www mentala com or give us a call Call now for more information or to order 800 794 2141 ee eee ase a nn ee eine Mental Automation Inc e 5415 136th Place SE Bellevue WA 98006 Phone 206 641 2141 e Fax 206 649 0767 CIRCLE 174 ON FREE INFORMATION CARD s31u01499 3 seindog Z664 snbny w Mm g oO Q pe 3 Popular Electronics Aug 4 EARN YOUR B S DEGREE COMPUTERS ELECTRONICS By Studying at Home Grantham College of Engineering now in our 47th year is highly experienced in distance education teaching by corre spondence through printed materials computer materials fax modem and phone No commuting to class Study at your own pace while continuing on your present job Learn from easy to under stand but complete and thorough lesson materials with additional help from our instructors Grantham offers three separate dis tance education programs leading to the following accredited degrees 1 the B S E T with Major Emphasis in Electronics 2 The B S E T with Major Emphasis in Computers 3 The B S C S the Bachelor of Scien
304. ve encountered any of the drawbacks usually associated with the ham or SWLing hobby then just maybe the low cost solu tion presented here will be af interest to you Our active antenna gives your ham rig or DX station the pull it needs to catch the com munications that you most want to hear William Sheets K MQJ and Rudolf F Graf KA2CWA4 54 DTMF Frequency Counter Put that old inoperative tone telephone back in service with the aid of this easy to build frequency detection circuit William K McKellips FEATURES 39 The New Old Autodyne Over the years many different receiver designs have been tried some of which were immediately found wanting and others achieved popularity for a while but fell out of favor when superior designs came along But the direct conversion receiver is a design that has come and gone and is now being resurrected using the new generation of electronics components Joseph J Carr 44 The Laser Fridge Learn how scientists have found a way to manipulate a device that s been shown to generate extreme heat to produce cold Douglas Page 45 Computers Are Helping The Blind And Deaf Here s a look at some new sophisticated software technology Page 12 which enables persons with minimal vision or profound hearing loss to see and hear again Bili Siuru POPULAR ELECTRONICS ISSN 1042 170 Published monthly by Gernsback Publications Inc 500 Bi County Boulevard Farmingdale NY 11735 Second C
305. ve ever seen With it s super sensi tive mike it transmits a whisper or a room of conversation to an FM radio tunable from 88 to 108MHz FM With a proper antenna it trans mits about 1 2 mile The kit is made with sur face mounted parts we have already mounted these parts You install the leaded parts Power requirement 6 to 12v DC Size 35 x 9 MMWM5 kit 34 95 TV NOTCH FILTERS FOR CHANNELS 2 thru 22 Many of our kits are available completely built Our TV filters eliminate unwanted TV channels or interference that alters both sound and video with a beep beep beep Works on cable channels 2 thru 22 only sold for educational purposes only You must obtain permission from your local cable company before using these filters on your cable system Send your call sign or call CQ automatically with the push of a button Change your message as often as you like The AUTO CALL enables you to electronically store a 20 second message of your choice Your call sign or call CQ for instance and send it with the push of a button Change your message as often as you like e Your message is stored in on board non volatile memory cells providing zero power data storage This is a high quality voice recording and playback unit RX 1 RX 1C SIZE 1 H x 2 4 W x 3 8 D KIT 49 95 CABINET 12 95 o This Manual contains schematics
306. vide people declared legally blind with sufficient sight to be considerably more indepen dent A computer program called to see and hear again BILL SIURU Soltis Nas been developed in France The Windows based Soltis software is used to calculate the optical dimensions for corrective eyeglasses that maximize the amount of light transmitted to the portion of the retina which is still functional even though the area may be quite smal As an optic instrument Measurements on the eye can be quantified to determine under what conditions light is trans mitted correctly to the retina The Soltis program utilizes photometric calculations that determine each ray of light through the lens from object to image According to M Yves Maigret the French optician at Espace Vision who along with a team of researchers at the University of Tours developed the technique for designing the corrective lenses their results show about 50 percent improvement of the patient s vision in the straight on direction This is enough vision so that the previously sightless can get around without a cane or seeing eye dog Soltis software offered commer cially by Optis Ze La Farlede locat ed in Toulon France is a real time ray tracing computer program used in designing a variety of pho soiu0djoe q seindog 7661 Isnbny J gt n Popular Electronics August 1997 A Lez An image is seen reflected on the still func tional porti
307. ws only half the time producing pulsating voltage across the load resistor Fig 1C When the circuit has two diodes pulsating voltage flows all the time across the load resistor Remember friends if you would like to try winning a book send a schematic and a description of the theory for a working circuit to Think Tank Popular Electronics 500 Bi County Bivd Farmingdale NY 11735 Send enough suitable circuits to fill a column and a chip and kit will be on the way too Getting back to our discussion topic last month mentioned house hold current is delivered as 11 volts AC That s okay for heavy duty appli ances containing just AC motors but it is not Suitable for most devices which typically require DC and at a low volt age Such Circuits usually contain a When current is cut off by the diode the transformer to reduce the voltage To refresh your memory about how that works take a look at Fig 1A That cir cuit is plugged into an AC outlet via PL1 and 117 volts AC is applied to the primary of step down transformer T1 The transformer reproduces the wave form at its secondary winding but ata reduced voltage That gets us closer to what we want since the voltage to the load is now at a lower value Consider what happens if we place diode D1 in series with the load The diode permits current to flow only when it is forward biased effectively cutting current off when the diode is rev
308. xi mately 1 inch in diameter that was placed on the author s unit to show the direction indicated by the lit LED along with a table showing the direction corresponding to each of the eight LEDs You can photocopy that pattern and scale it to fit your unit or you can devise a design of your own If you choose you can even omit it all together Operation Before applying power verify that the power source input Continued on page 78 JOSEPH J CARR ver the years many different receiver designs have been tried out by designers Some of them were immediately found wanting Others were popular for a while but fell out of favor when superior designs came into play For example the tuned radio frequen cy TRF radio went out of fashion in the late 1920s or early 1930s when the RCA owned superheterodyne design became more widely used and it is still used today Other designs were popular for a while went into eclipse and then were resurrected when newer technolo gies made them viable again One such receiver design is the auto dyne or direct conversion design lf you understand the principles behind the superheterodyne receiver then you will find it very easy to understand the autodyne for it is similar in basic concept Therefore let s start our discussion with the more familiar superhetero dyne design which forms the basis for almost all modern radio and television receivers O Heterodyne Receivers
309. y 3 iInch square cutout was made in the front panel of the enclosure for the display board The display board was then bolted in place on the inside of the enclosure using 1 inch bolts with inch spacers so that the LED displays show through the square hole A 1 by 3 the circuit The display should light and the readout should show zeros across the board Press any two row or column keys on the telephone keypad Depending on the row or column in which the keys are locat ed the display should show one of the numbers shown in Fig 4 For instance if you press 1 and 4 in the first Column the readout should dis play 1209 Or if you press 1 and 2 in the first row the readout should show 677 Note The values displayed are in hertz Hz The DTMF Frequency Counter should make a very handy com panion to a telephone test box Maybe you already have a tele ohone put away in the closet that sounds OK but won t dial out The DTMF Frequency Counter might be able to tell you why On some phones you can even adjust the powdered iron slugs in the tele phone pad s oscillator and put the oscillator on frequency You may run into a phone that is wired with the green and red wire swapped inside the phone The polarity of the 5 volt supply to the phone would be reversed and there would be no tones af all In such cases just swap the red with the green wires on the connection block inside the phone E s21u01 9943 Jeindog
310. y Mail Orders Delivered in the State of California must include California State Sales Tax NO C O D Shipping and Handling 5 00 for the 48 Continental United States ALL OTHERS including Alaska Hawaii P R and Canada Must Pay Full Shipping Quantities Limited Prices Subject to change without notice CIRCLE 28 ON FREE INFORMATION CARD Our 1 Best Selling Home Electronics Repair Manual FREE _ WEKA S GIANT a 900 PAGE BIBLE OF EASY i x pa e pea Dee a TN Se yee _ we w aas nua 2 a po aama 0 VCR mad Ot oo ina bare OE maa ae eae AO poet 1 pe hoes et FILLED WITH Troubleshooting Diagnostic Tips Step By Step Model l E Specific Instructions a Te Charts Photos amp Easy ALL THE INSTRUCTIONS YOU NEED TO FIX To Follow Diagrams TVs VCRs STEREOS CAMCORDERS PHONES CD PLAYERS FAXES PLUS Directory Of COMPUTERS WALKMANS AUTO RADIOS VIDEO GAMES amp MORE Parts Dealers Don t Waste Time amp Money At Electronics Repair Shops Ug di NOW FIX IT YOURSELF FOR SAVINGS FE Py yy 4 139 PROFIT AND SATISFACTION FAX 1 800 256 5915 E MAIL WEKA Publishing compuserve com 7 gael WEKA PUBLISHING INC 1077 Bridgeport Ave Now you dont have to be a profes electronics principles to advanced P O Box 886 Shelton CT 06484 sional technician to get PERFECT troubleshooting and repairs ti YES Please rush my ELECTRONICS REPAIR MANUAL I ll
311. y at home learning separately or earn College l All you need is the CD ROM no expensive credits books or lab equipment is required The choice is yours Buy the CD ROM and Complete each course at your own pace use it as the ultimate electronics reference schedule the time that s best for you and tool to refresh your knowledge of electronics decide how quickly you finish each Course or enroll in the program and earn College The typical completion time is 48 weeks of credits The course material is delivered part time study but there are no time limits using video text 2 D and 3 D animations color photos audio and over 450 laboratory projects Use the CD ROM in the home office or shop as a troubleshooting design Call now Toll Free tool and reference guide Call our 24 hour toll free hotline to find out more about the Electronics Technician Industry Recognition CD ROM or the distance education program The course content for the CD ROM was qd 8 8 8 5 3 5 3 3 3 developed in association with some of the gt 7 top corporate trainers In North America George Brown College 160 Kendall Ave Toronto Canada s1u04399 4 4eiNdog Z664 IsNony and focuses on practical applications and M5R 1M3 Fax 416 415 4727 web site http www gbrownc on ca troubleshooting techniques Popular Electronics August 1997 AA j e A J a A V i a E LY a a a i i Ad U a I j ih Gj A About the Changes Tak
312. y debut of new chanaels r Often in the clear for merths Dish Movers 12 to 52 for all n or asi he C and Mu band dishes Wild feeds Actior as i happens LNBs Programming you want at price All kinds you can afford to pay to heat up your picture Whether you re considering your first Tune Up Kits f r C Ku band amp DBS satellite TV entertainment system or s looking for an upgrace to your Programming current system Skyvisicn provides Save 30 50 with Skypac the best in hardware technical Support support convenience Customers enjoy toll free technical help low cost aad service 1048 Frontier Drive Fergus Falls MN 56537 All marks shown are registered trademarxs Fax 21 8 739 48 79 int l 21 8 739 5231 of their resp e owners s31u01 798 3 seindog 7661 isnbny BORK ELE amp Skyvision www skyvision com co i Popular Electronics August 1997 ee RO INTERNET NOT Pare FOUND IN yp IORS SECRE 1 BOOKSTORES V EM RF radar ultrasonic IR CONSUMER TRONICS conte ro a ind Persona dinvention P O Box 23097 ABQ NM 87192 needs Descri include nonrefundable 30 tions Satanas ORDER TODAY 505 237 2073 OFF THE SHELF Fax 505 292 4078 HARDWARE Web Adventure www tsc global com Van Ec stems x Data Card Keader Writers RF EM uWave Radar Ultrasonic IR Established in 1971 Featured on CBS 60 Minutes Forbes New York Times Light Sound Detectors Xmitters Jammers
313. y to report that while not perfect Pilots recognition system is definitely usable without a lot of training and without any significant real time slow down Pilot comes with its own PC based PIM Part of the process of using Pilot involves per forming periodic one button Hot sync desktop PIM The PIM is all but worth less except as a means of getting data from Pilot to the PC However because of Pilot s popularity most major PIMs can sync with Pilot and that was the solution eventually set tled on even though the story is still between the unit and the not over More next time on the soft ware packages a Twenty one states have passed computer crime laws directed toward prosecuting abuse Go with it our state is lying idle SCANNER SCENE Continued from page 58 Wireless Online Inc in California as WA2XEH is testing narrow band PCS on 901 35 901 45 901 8375 901 90 930 75 931 00 and 940 90 941 00 MHz Spaced out Radio Did you know that your scanner can monitor some of the frequencies used to tune in natural and man made transmissions from the cosmos Owning an externally mounted anten na and preamplifier will substantially aid in your pursuit of this interesting but little promoted area of the hobby Radio astronomers tune to 37 50 38 25 and 73 00 74 60 MHz to detect the naturally occurring radio signals from the galaxies interstellar clouds Jupiter and the
314. z 1 049 95 HP 9060 60MHz 15 HP 91 50 1 50MHz 22 HP 9250 250MHz 29 HP 9258 250MHz 100 1 39 Single Output DC Power Supplies Dual Tracking Short Circuit and overload protected e Short Circuit amp overload protected e Constant current constant voltage mode e Constant current amp constant mode 0 02 2mV line regulation 0 02 2mV load regulate Independent or Tracking s P y PS 303D 314 95 30V 3A 30V 3A PS 305D 399 95 30V SA 30V SA PS 8108 549 95 60 V 3A 60V 3A PS 8109 699 95 60V SA 60V SA PS 8102 399 95 30V 3A 30V 3A PS 8103 489 95 30V SA 30V SA amp pi Analog Meters Display PS 303 159 00 30V 3A PS 8200 179 95 30V 3A PS 305 219 95 30V SA PS 820 239 95 30V SA PS 8110 289 95 60V SA gt PS 8112 399 95 60V SA p PS 8202 499 95 30 V 3A 30V 3A PS 1610 289 00 16V 10A PS 8300 199 95 30V 3A PS 8203 549 95 30V SA 30V SA PS 8107 INSTEK Test amp Mea 399 95 30V 10A _ PS 8301 259 95 30V SA suring I Cert 934163 2 Yea ON 653 699 95 99 95 SOME Triggering 20 MH Osei Meoseagre Septet f d jD of wee r e wa wa az 2 variable out 0 30V 0 3A One fixed SV 3A output High stability low drift One fixed V 3A output DM 8034 179 95 3 4 dgt e AC DV V A

compass - American Radio History

Contents

Download Pdf Manuals

Related Search

Related Contents