"service manual"
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1. HEWLETT PACKARD L 0 0 Operational Amplifier Basics Introduction It can be mathematically shown that if an amplifier has an infinite high gain a an infinite bandwidth an infinite high input impedance and a zero output impedance then its characteristics can be totally determined by external components connected in feedback loops Such an ideal operational amplifier op amp is shown in Figure 1 Since R is infinite there is no current flow into either input terminal and the differen tial input voltage is zero If there is an output voltage Eo present it can only be the result of an infinitesimal voltage at the input These are theoretical considerations only Ew 0 Eo 0 Figure 1 Ideal Operational Amplifier Pub No 5952 3458 The op amp is therefore an ideal building block for all kinds of analog tasks In practice no single charac teristic listed above can be fully achieved The values that can be prac tically obtained are nevertheless such that the resulting performance is extremely useful Op Amp Fundamentals An op amp is a very high gain dc amplifier and usually has voltage gains in the range of 20 000 to 1 000 000 The detailed schematic symbol of an op amp is shown in Figure 2a with the simplified symbol shown in Figure 2b As shown in Figure 2a the input of the op amp is called the inverting input and the input is called the noninverti2. The simple integrating op amp shown in Figure 13 produces an output signal proportional to the integral of the input signal and time variable of the resistance and capacitance charging rate The capacitor connected across the input and output of the inverting op amp improves the performance by what is called the Miller Effect The Miller Effect says that a capacitor con nected as shown appears to the input as being multiplied by the gain of the amplifier If R 1 megohm and C 1 micro farad according to the formula shown in the figure Eo will increase at a rate of 1 volt per second positive or negative depending on the polar WWW HPARCHIVE COM fo Eo ae E ee GAIN R Figure 12 Simple differential operational amplifier ity of Ew If Ew is a symmetrical square wave Eo will be a triangle wave For Emn sin X the output is cos X The output leads the input by 90 The Differentiator Op Amp As shown in Figure 14 Eo is propor tional to the rate of change of the input voltage A dc input will make Eo O because of the blocking capacitor C A square wave at the input will produce a spike at the out put triggered by the leading and trail ing edges of the input signal Because the top of the square wave is a con stant value the differential factor is zero and the integrating capacitor dis charges towards zero The Logarithmic Converter Op Amp If a nonlinear element such as a trans istor i
3. Modification to install Option 201 in a standard HP 4285A 022 Modification to install Option 202 in a standard HP 5285A 022 Modification to install Option 301 in a standard HP 4285A 022 Modification to install Option 001 in a standard HP 4285A 022 Instructions for mounting a new diode on the HP 4332A A3 Power Supply Bd 022 2ND QUARTER 1990 WWW HPARCHIVE COM C SN SN Type No IO IO MA IO IO MR MA IO IO IO IO IO IO MR IO MR MR MR MR MA IO MR MR MR MR IO IO IO MR SA PR PS MR SA PR PS MR MA MR MR MR MR IO MR IO MR MR 4934A 04 4934A 05 4934A 06 4934A 07 4934A 08 4934A 09 4936A 02B 4936A 11 4936A 12 4947A 11 4947A 12 4951A 21 4951B 05 4951C 10A 4951C 12 4952A 08C 4952A 10A 4952A 11A 4952A 11C 4952A 12 4972A 05 4992A 01 5061A 21 5061B 02 5316B 02 5334B 04 5334B 05 5342A 26B 5347A 01 5347A 02 S 5347A 03 S 5347A 03A S 5348A 01 5348A 02 S 5348A 03 S 5348A 03A S 5361A 01A 5361A 02A 5370B 03 5370B 04 5371A 02C 5371A 13A 5372A 01 5372A 02 6060A 01 6060A 02 6063A 01 2ND QUARTER 1990 Abstract Service Note Package Instructions for correcting step 6 of the Transmitter Distortion Performance Test 017 Preferred replacement diode bridges on the transmitter receiver interface assy 017 Retrofit instructions for instaling special Option H05 increased monitor volume 019 Incorrect battery P N appears in the service manual change to 1400 0378 019 Some units were
4. Recommended modification to prevent HP IB hangup 023 Modification to correct defective cable assembly 017 Mod of replacement A1 keybd amp disp assy for use in older inst 020 Recommended modification to prevent HP IB hangup 023 Mod to prevent HP IB hang up 020 Mod to prevent HP IB hang up 020 Modification improves measurement repeatibility in measurement mode 9 2 special 019 Rec mod to use E1212B I O boards with 126 Kbytes memory depth 023 Instructions for connecting power control module suppression capacitors 023 Mod available to install a new Emergency Switch Off protector 023 Instructions for performing routine dielectric withstand test HIPOT 017 How to use the internal DSA capabilities to isolate faults 020 Rec mod to prevent reading of bad status and address information 023 Mod to correct faulty thermal fuses inside the oscillator housing 020 HP 11990A software upgrade is available 018 Repair faulty touchscreens with board replacement not component level repair 020 New CPU board increases memory capacity from 1 0 to 2 5 megabytes 020 Repair procedure for POD cable connectors J1 J5 HP P N 1251 8158 017 Repair procedure for POD cable connectors J1 J5 HP P N 1251 8158 017 Modification to prevent turn on and or PV loop POD errors 017 Modification to prevent the control leads from turning on at power up 019 Procedure to program module ID info into replaced digital assy after repair 020 Notification that the fuse label contains t
5. amp procedures when using the EMPRO current shunts for calibration 019 MR 60502A 01 Rec addition of a 0 5 amp fuse to protect the bias transformer circuit 019 IO 60502A 02 Oper inst amp procedures when using the EMPRO current shunts for calibration 019 MR 60504A 01 Rec addition of a 0 5 amp fuse to protect the bias transformer circuit 019 IO 60504A 02 Oper inst amp procedures when using the EMPRO current shunts for calibration 019 MA 70001A 12A Mod available to convert Mainline Switch actuator from pull ON to push ON 023 MA 70001A 12 Mainline switch conversion kit changes on off positions 021 IO 70001A 13A Replacing A1 Pwr Sup Assys in mainframes with pull ON Mainline switches 023 IO 70001A 13 Mainline switch conversion kit changes on off positions 021 IO 70004A 02 Rack mount with slides kit is now available 020 IO 70004A 03 Replacement of keypad retainer spring 021 MA 70300A 05 Recommended replacement for the RF converter HP P N 5086 7737 017 IO 70300A 07A Replacement for obsolete attenuators 021 IO 70300A 07 Replacement of obsolete attenuators 017 MR _ 70300A 08 Modification to update HP 70300A module verification software revision A 03 02 018 IO 70600A 01B Replacement of A12 YIG driver board assy or A13W1 MSIB cable assy 021 IO 70600A 02A Replacement for obsolete attenuators 021 IO 70600A 02 Replacement of obsolete attenuators 017 MR 70600A 05 Recommended modification to the module verification software 020 IO 70601A 01B Replacement o
6. MHz oscillator during extreme temp changes 019 MR _ 8770A 20 Repl covers improve RE2 test emissions for the 8770A 019 IO 8780A 01A Firmware history 022 MR _ 8780A 07B A7 FM BB Relay troubleshooting and replacement procedure 017 IO 8780A 09 Instructions for installing bias current adjustment resistor 017 MR 8780A 10 Recommended A15A2 RF output amplifier and firmware version 2 2 020 16 BENCH BRIEFS WWW HPARCHIVE COM 2ND QUARTER 1990 C SN Type MR MR MR MR MR MR MR MR MR MR MR MR IO MA SA IO MR MR MA IO MA IO IO MR MR IO SA MR MA MA MA MR MR IO IO IO IO IO IO IO IO IO MR IO IO IO IO SN No 8780A 11 8780A 12 8901A 03 8901B 04 8901B 06 8902A 08 8902A 09 8902A 11 8903B 06 8903E 06 8970A 13A E1222M 02 E1222M 03 E1222M 04 E2500A 01 S E2500A 02 10314D 01 10811A B 03 11990A 02 16500A 07A 16500A 09 16510A 02 16510B 01 18160A 01C 18160A 02 35651B 01 35660A 04 S 37180A 01 37203A 12 37204A 01C 37204A 03 41800A 01 42841A 02 54111D 12 54112D 05 54120A 02 54120A 03A 54120A 03 54121A 02A 54121A 02 54201A D 14 54201A D 15 54502A 01 54502A 02 54502A 03 54503A 01 54503A 01 2ND QUARTER 1990 Abstract Service Note Package A6 FM RF Relay troubleshooting and replacement procedure 017 Modification to correct baseband calibration errors 022 Recommended modification to prevent HP IB hangup 023 Mod of replacement A1 keybd amp disp assy for use in older inst 020
7. The part numbers are WWW HPARCHIVE COM Update service 5951 6517 Please note that automatic shipments of the update service will no longer be made If you want to continue to receive quarterly updates to the microfiche library you must place a new order during the first month of each quarter May August Novem ber February Note that inventory will be purged at the end of each quarter Contact your local HP sales service of fice for more information 2ND QUARTER 1990 uP DIREC Fast Ship Icon oP Call HP DIRECT For Same Day Shipping When you see the fast ship icon KOJ in the HP Direct Instruments Now catalog you know the quickest way to get the products listed is to call HP DIRECT before 4p m your time Your order will ship by 7 p m the same day And get to you within seven working days HP DIRECT same day shipping starts with warehouses in California and New Jersey where a full range of HP Test and Measurement products and computer supplies are in stock 99 7 of the time And itis supported by knowledgeable sales consultants staffing the dedicated toll free phone lines ready to help you with your order gt Complete range of products From BNC cables to protocol analyzers and accessories e Thorough documentation Complete product pricing and ordering information in the HP DIRECT Instruments Now catalog o Helpful toll free telephone ordering Just call 800 538 8787
8. an op amp is stability If the input is zero the output will also be zero The op amp must be free of drift or offset voltage The Noninverting Op Amp In the configuration shown in Figure 9 Ew and Eo are in phase The closed loop gain is controlled by the ratio of R and R If R 0 then the amplifier is simply a voltage follower and R becomes meaningless However in practical applications it will be made WWW HPARCHIVE COM equal to the Ey source impedance for balancing purposes of the differential input stage The Inverting Op Amp Ep and Eo are inverted as is indicated by the negative sign for the gain see Figure 10 R may be included instead of a ground connection of the nonin verting input only because of a less than ideal amplifier less than infinite input impedance R should be equal to R again for balancing purposes If the characteristics are close enough to ideal then input B is at ground level By definition input A must also be at ground level since there shall be no potential difference between in puts A and B Point A is called a vir tual ground Figure 8 Simple voltage divider with op amp providing isolation Figure 9 Simple noninverting op amp BENCH BRIEFS 3 R R 1FORR Rp hk Figure 10 Simple inverting operational amplifier The Summing Op Amp The summing op amp shown in Figure 11 is simply an inverting op amp with multiple inputs Since input A is a
9. eliminate the confusion that nor mally exists between accuracy and precision the following example will serve to show the difference Example Assume that two meters are used to measure a perfect 100 00 volt power source Ten readings are taken with 2ND QUARTER 1990 each meter Figure 1 shows a range from 97 16 to 97 24 volts and Figure 2 shows a range from 99 1 to 100 7 volts When we compare the ranges of the two meters we find that meter 1 has a spread of 0 08 volts and meter 2 has a spread of 1 6 volts This defines meter 1 as having 20 times the preci sion than meter 2 has i e 1 6 08 20 But meter 2 is closer in its readings to 100 00 volts which indicates that precision by itself does not necessarily produce accuracy Meter 2 is more accurate than meter 1 Now as shown in Figure 3 if meter 1 were recalibrated with adjust ment to agree with the perfect calibration source the spread of its readings would likely range from 99 96 volts to 100 04 volts a spread of 0 08 volts While this shows that precision and accuracy combine to pro vide greater confidence in the use of an instrument the two are truly inde pendent However the best of both are desirable in any measurement situation Errors in Measurement There are three types of errors by which you may be confronted They are gross errors systematic errors and random errors Gross Errors These errors are strictly unde
10. not in use Service Note Order Form If you want to order a service note refer to the list of service notes in the index and find the service note number belonging to the product you are interested in Using the form on this page order the number that ap pears in the service note package column You will receive a package of service notes that includes the one you ordered Hewlett Packard Worldwide Customer Support Operation 100 Mayfield Ave Mtn View California 94043 Attn Bench Briefs NAME COMPANY NAME ADDRESS CITY STATE COUNTRY Service Note Packages g 017 g 021 O 018 O 022 oO 019 O 023 o 020 ZIP Please photocopy this order form if you do not want to cut off the page HEWLETT PACKARD COMPANY 100 Mayfield Avenue Mountain View California 94043 BENCH BRIEFS 2ND QUARTER 1990 Volume 30 Number 2 Service information from Hewlett Packard Company To obtain a qualification form for a free subscription send your request to the above address Reader comments or technical article contributions are welcomed Please send them to the Bench Briefs Editor at the above address Editor Jim Bechtold Hewlett Packard 20 BENCH BRIEFS All rights reserved Permission to reprint Bench Briefs granted upon written request to the Editor WWW HPARCHIVE COM Bulk Rate U S Postage PAID Santa Clara CA Permit No 80 Printed in U S A 2ND QUARTER 1990
11. shipped with incorrect serial prefix of 2737U should be 2937U 019 Mod to prevent battery power supply fuse failures during power on 020 Retrofit for battery operation Options 001 and 003 017 Preferred replacement diode bridges on the switch board assembly 017 Preferred replacement top and bottom covers 022 Preferred replacement for current bridge rectifier ASSCR3 4 017 Preferred replacement of A2U8 021 Recommended replacement resistors if the display is dim 017 Recommended replacement resistors if the display is dim 017 Modification to correct intermittent disk drive failures 022 Cross reference of keyboard cable applications 022 Modification to improve the current output of the power supply 017 Modification to correct intermittent disk drive errors 019 Modification to reduce the current drain on the CIO chip A1U209 017 Modification to eliminate intermittent DLC errors 019 Notification of system firmware upgrade 019 New memory board upgrade and repair 020 Rec mod to prevent POWER ON lockup state due to ac line fluctuations 023 Faulty Q4 amp Q10 transistors found in the A11 Ceasium Oven Controller 019 Faulty Q4 amp Q10 transistors found in the A11 Ceasium Oven Controller 019 Instructions for correcting the HP IB Gate time test failure 017 Must replace all 7 segment LEDs when one fails 017 Repair of oven oscillator should be by replacement 017 Installation of amplitude measurement Option 002 021 Modification to improve power supply relay rel
12. test which will be conducted free of charge o BENCH BRIEFS 7 The Logistics Data Book 1990 The Logistics Data Book is designed to assist Hewlett Packard s government customers with their logistics needs associated with the support of HP products Information is drawn from HP records and Department of De fense information It reflects logistics actions through October 1989 The types of HP products covered in this publication include electronic components medical instruments and systems computer equipment calculators instruments and systems for chemical analysis and electronic test and measuring systems The intent of the Logistics Data Book is to include HP model numbers and their various options that are pur chased by government customers Additional information on all HP parts having National Stock Numbers may be found in the microfiche NSN HP Cross Reference Publication No 5957 4171 Options are usually identified in HP product literature by a three digit number following the model number e g HP 1234A Option 003 Other options may be designated as a letter and two numbers after the model number e g HP 1234A Option H02 Modifications and systems may be identified in HP literature with a single alpha and two digits preceding the model number e g E12 1234A For procurement purposes all op tions and modifications in this book follow the model numbers and are connected to them by hyph
13. that lie below the mean value It is the general nature of a measured variable that there will be a distribu tion of values both plus and minus around the true or actual value Note that it is never possible to know the true value since there will always the quantity being measured another some preliminary observa be some small error o Important Notice about Service Notes Service notes contain product specific Bench Briefs Library 5951 6511 service information for Hewlett Pack ard s electronic products Subjects in clude product improvements modifi cations and procedures for trouble shooting maintenance and repair Service Notes are published as ap propriate throughout the life of a product All new notes are an nounced in Bench Briefs Please note that Hewlett Packard has restructured the procedure for hand ling and distributing instrument re lated service notes through Bench Briefs and the microfiche program 10 BENCH BRIEFS If you want to order a service note refer to the list of service notes in the index find the service note number belonging to the product you are in terested in and note the package number Use the form on the last page of Bench Briefs to order the number that appears in the service note pack age column You will receive a pack age of service notes that includes the one you ordered Microfiche Service notes are still available on microfiche
14. to prevent the display intensity from dimming intermittently 023 ROM upgrade kit is available 020 Modification to reduce 80 kHz power supply sidebands 017 Modification to eliminate display flicker 018 Bypass capacitor added to A15 assembly to improve residual responses 019 Availability of a new temperature controlled crystal oscillator 018 A new A12 RF switch is available for instruments without Option 026 017 Recommended replacement for obsolete second converter 017 Modification to prevent intensity offset failure caused by parasitic oscillations 018 Modification to reduce baseband noise when using 08562 60094 power supply assy 018 Modification available to install dc protection in the Low Band Input 023 Mod to add dc blocking capacitor to low band input 020 Mod to update test amp adj modules to test later ver of port SA assys 020 Updating test and adj modules to Test Later versions of portable spect assys 017 Modification to eliminate 1 8 MHz sampler buffer oscillation at high temperatures 017 Electrolytic capacitor changes on the A16 Cal oscillator Assemblies 019 Modifications required when replacing ASCR401 PIN diode 019 Rec Mod to A14 to stabilize the 10 V reference 023 Mod to correct intermittent connector to oven controlled oscillator 020 Modification available to upgrade the instrument to Option K 74 023 Modification to prevent the display intensity from dimming intermittently 023 ROM upgrade kit is available 020 WWW HPARCHIVE
15. video out upgrade kit 018 MR 70903A 02A Module verif S W changes eliminate errors when performing module gain adj 018 IO 70904A 02 Recommended replacement of the RF converter HP P N 5086 7737 017 IO 70904A 03B Replacement of A4 Power Supply Cntl Assy or W13 MSIB cable assy 021 IO 70904A 05A Replacement for obsolete attenuators 021 IO 70904A 05 Recommended replacement for obsolete attenuators 018 MR 70904A 08 2nd converter phase lock loop align adj seq is modified in S W rev A 03 00 018 IO 70905A 02B Replacement of A4 Power Supply Cntl Assy or W13 MSIB cable assy 021 18 BENCH BRIEFS WWW HPARCHIVE COM 2ND QUARTER 1990 SN SN Abstract Service Note Type No Package IO 70905A 05A Replacement for obsolete attenuators 021 IO 70905A 05 Recommended replacement for obsolete attenuators 018 MR 70905A 08 2nd converter phase lock loop align adj seq is modified in S W rev A 03 00 018 IO 70905B 01B Replacement of A4 Power Supply Cntl Assy or W13 MSIB cable assy 021 MR 70905B 06 2nd converter phase lock loop align adj seq is modified in S W rev A 03 00 018 IO 70906A 02B Replacement of A4 Power Supply Cntl Assy or W13 MSIB cable assy 021 IO 70906A 05A Replacement for obsolete attenuators 021 IO 70906A 05 Recommended replacement for obsolete attenuators 018 MR 70906A 08 2nd converter phase lock loop align adj seq is modified in S W rev A 03 00 018 IO 70906B 01B Replacement of A4 Power Supply Cntl Assy or W13 MSIB cabl
16. 142B 04 4142B 05 4142B 06 4145A 13 4145B 04 4145B 05 4193A 04 4194A 09 4195A 05 4195A 06 4195A 07 4195A 08 4195A 09 4195A 10 4261A 01 4262A 18 4276A 05 4276A 06 4277A 09 4277A 10 4278A 06 4279A 01 4280A 08 4284A 09 4285A 01 4285A 02 4285A 03 4285A 04 4285A 05 4332A 01 12 BENCH BRIEFS Abstract Service Note Package Retrofitting Option 010 Printer or Option 011 Disk Drive 021 Mod to eliminate noise from HP 3789B Input Port 020 PROM update kit information 020 Firmware hardware revisions and their impact on automated performance testing 020 Retrofitting Option 100 Weco 477 connectors 021 Retrofitting Option 200 BNC connectors 021 Adding enhancements to older units 021 Instructions to fit PROM upgrade kits 021 Rec part repl to prevent damage to the PSM by surge current 019 Recommended part replacement to prevent damage to the PSM by surge current 017 4142B upgrade for Revision 5 6 system software feature 019 SMU repl to eliminate AFU test failures 019 Rec part repl to prevent damage to the PSM by surge current 019 Recommended part replacement to prevent damage to the PSM by surge current 017 4142B upgrade for Revision 5 6 system software feature 019 SMU repl to eliminate AFU test failures 019 Rec part repl to prevent damage to the PSM by surge current 019 Recommended part replacement to prevent damage to the PSM by surge current 017 SMU repl to eliminate AFU test failures 019 Mainframe upgrade for the HP 4142
17. 16Q2 transistors 019 IO 6140A 03 Rec repl for the A13Q2 A14Q2 A15Q2 and or A16Q2 transistors 019 MR 6625A 01 Mod to correct store recall function 020 MR 6626A 01 Mod to correct store recall function 020 MR 6628A 01 Mod to correct store recall function 020 MR 6629A 01 Mod to correct store recall function 020 MA _ 8112A 06 New fan does not need a motor control assembly 019 MA 8116A 08 New fan does not need a motor control assembly 019 SA 8340A B 30 S Possible injury from falling instrument if the handles have been damaged 019 SA 8341A B 30 S Possible injury from falling instrument if the handles have been damaged 019 IO 8485A 01 New O amp S manual 08485 90001 provides expanded troubleshooting info 019 IO 8485A 01 New operating service manual provides enhanced troubleshooting procedures 020 MA 8508A 01 A5U18 EPROM Assembly HP P N 08508 80010 replaced by HP P N 08508 80012 017 IO 8508A 02 Introduction of the Input Module Extender 08508 60032 as a service tool 019 MR 8510B 03 Mod to correct firmware revision 5 0 problems 020 MA 8516A 04B Improved frequency converter requires new bias supply 019 MA 8559A 32 Availability of an extender cable reinforcing kit 018 MA 8560A 01B New firmware upgrade kit is available 020 MA 8560A 01 Firmware upgrade kit 017 MA 8560A 02 Modifications required when replacing A5CR401 PIN diode 019 MR 8560A 03 Electrolytic capacitor changes on the A16 Cal oscillator assemblies 019 MR 8560A 04 Rec Mod to A14 to stabiliz
18. 2A HCU 019 Repl PROMs prevent spikes when the SMU reaches compliance 019 Repl PROMs prevent spikes when the SMU reaches compliance 019 Update Sys Disk to Rev 1 30 to improve perf in HP IB SRQ output function 019 Instructions for mounting a new diode on the HP 4193A A20 Power Supply Bd 022 Modification to install Option 001 into a standard HP 4194A 019 Modification to remedy uneven display color 019 Modification to install Option 001 into a standard HP 4195A 019 Modification to eliminate spurious vert white line on the CRT display 019 Mod to improve the Second Third IF converter gain adjustment range 020 Mod to improve source dc bias full scale adjustments 020 Modification to improve the power sweep linearity 022 Instructions for mounting a new diode on the HP 4261A A9 Power Supply Bd 022 Instructions for mounting a new diode on the HP 4262A A9 Power Supply Bd 022 Instructions for mounting a new Ni Cad battery on the mother board 019 Repair method for the A1 Logic Board 020 Instructions for mounting a new Ni Cad battery on the mother board 019 Repair method for the A1 Logic Board 020 New EEPROM sockets added to new A7 boards check before ordering new board 019 New EEPROM sockets added to new A7 boards check before ordering new board 019 Mod to correct noise on the dc power lines due to misloaded capacitors 020 Procedure for ordering new ROMless repl brd for the A7 CPU brd 019 Modification to install Option 002 in a standard HP 4285A 022
19. 44 Preferred replacement of A3U33 and A204U47 021 IO 3779A 61 Preferred replacement for EPROMS A24 U31 and U41 020 IO 3779A 62 Firmware upgrades 021 IO 3779B 65 Firmware upgrades 021 IO 3779C 12C Preferred repl board assemblies that comply with VDE specifications 019 MA 3779C 43 Small modification required when replacing A16 Assembly 019 IO 3779C 44 Alternative recommended test equipment for performance tests 021 IO 3779D 12C Preferred repl board assemblies that comply with VDE specifications 019 MA 3779D 47 Small modification required when replacing A16 Assembly 019 IO 3779D 48 Alternative recommended test equipment for performance tests 021 MA 3787B 04E Newer features can be retrofitted to earlier 3787B instruments 019 IO 3787B 09 Notification of firmware updates 019 MR 3787B 10 Mod to eliminate crosstalk when performing loopback in Near Far mode 020 MR 3788A 01 Modification to prevent synchronization loss while measuring code errors on live data 022 2ND QUARTER 1990 1990 Bench Briefs Instrument Service Note Index WWW HPARCHIVE COM BENCH BRIEFS 11 SN SN Type No IO MA MA IO IO IO MA IO MR MR MA MR MR MR MA MR MR MR MR MA MR MR MR IO MA MR MA MR MR MR MR IO 10 IO IO IO IO IO IO MR IO MA MA MA MA MA IO 3789B 03 3789B 04A 3789B 05A 3789B 07 3789B 08 3789B 09 3789B 10 3789B 11 4062C 02A 4062C 02 4062C 03 4062C 04 4062UX 02A 4062UX 02 4062UX 03 4062UX 04 4142B 04A 4
20. 8B 21 Rec repl for the LO amplifier kit 019 MR _ 8568B 27 Mod to correct oven oscillator thermal fuse failure 021 MR 8568B 28 Rec repl of def SAW resonators prevents 275 UNLOCK and low 280 MHz output 023 IO 8569A 14A Replacement of obsolete attenuators 021 IO 8569A 14 Replacement of obsolete attenuators 017 IO 8569B 12A Replacement for obsolete attenuators 021 IO 8569B 12 Replacement of obsolete attenuators 017 IO 8570A 02A Replacement for obsolete attenuators 021 IO 8570A 02 Replacement of obsolete attenuators 017 MR 8590A 14 Modification to the A14 Log Board assy to assure proper switching of control lines 017 PS 8657B 01 S Possible shock hazard if toriodal mains xfmr s insulation damaged by A14 heatsink 019 MR 8673B 19 Recommended replacement of quartz oscillator thermal fuses to improve reliability 023 SA 8719A 01 S Possible injury from falling instrument if the handles have been damaged 019 SA 8720A 05 S Possible injury from falling instrument if the handles have been damaged 019 SA 8720B 01 S Possible injury from falling instrument if the handles have been damaged 019 MR 8752A 01 Firmware revision 1 00 problem corrections 017 MR 8753B 01 Modification to correct display flicker problem 017 MR 8753C 01 Firmware revision 4 00 problem corrections 017 SA 8757C E 02 S CPU battery may leak and damage the CPU board 019 MR 8770A 19A Modification to improve the reliability of the 125 MHz oscillator 022 MR 8770A 19 Mod improves tuning range for 125
21. COM BENCH BRIEFS 15 SN SN Abstract Service Note Type No Package MR 8563A 03 Rec Mod to A14 to stabilize the 10 V reference 023 IO 8563A 04 Oven controlled crystal oscillator retrofit kit is available 020 MR 8563A 05 Mod to correct intermittent connector to oven controlled oscillator 020 MR 8563A 07 Modification to prevent the display intensity from dimming intermittently 023 IO 8565A 23A Replacement for obsolete attenuators 021 IO 8565A 23 Replacement of obsolete attenuators 017 MR 8566A 39 Mod to correct oven oscillator thermal fuse failure 021 MA 8566B 11B A15 controller assembly firmware repl kit 019 MR 8566B 33 Mod to correct oven oscillator thermal fuse failure 021 MA 8567A 01A A15 controller assembly firmware repl kit 019 MA 8567A 08 Rec repl for the LO amplifier kit 019 MR 8567A 11A Mod to eliminate frequency spurs to improve performance 020 MR 8567A 11 Frequency spur correction 019 MR 8567A 13 Rec repl of def SAW resonators prevents 275 UNLOCK and low 280 MHz output 023 MR 8568A 46A Mod to eliminate frequency spurs to improve performance 020 MR 8568A 46 Frequency spur correction 019 MA 8568A 54 Rec repl for the LO amplifier kit 019 MR _ 8568A 55 Modification required when replacing ASAT1 019 MR _ 8568B 04A Mod to eliminate frequency spurs to improve performance 020 MR _ 8568B 04 Frequency spur correction 019 MA _ 8568B 10A Option 462 Retrofit kit 019 MA 8568B 11B A15 controller assembly firmware repl kit 019 MA 856
22. Cus tomer Service Center for repair HP 8757C E Scalar Network Analyzer Safety Service Note 8757C E 02 S de scribes a possible defective lithium battery contained on the CPU board of the instrument The battery may leak electrolyte and damage the board Symptoms include yellowing around the battery or in some cases corrosion of the board and other boards in close proximity The Safety Service Note contains a list of applic able serial numbers Please return your unit to the nearest HP Customer Service Center for repair HP 85620A Mass Memory Module Safety Service Note 85620A 03 S de scribes a possible defective lithium battery contained on the mass mem ory module of the instrument The battery may leak electrolyte and dam age the board Symptoms include yel lowing around the battery or in some cases corrosion of the board and other boards in close proximity The serial number range of affected instru ments is 0000A00000 3003A00604 If you possess one of the affected units please return it to the nearest HP Cus tomer Service Center for repair HP 86792A Agile Upconverter Safety Service Note 86792A 02 S de scribes how to safety check the routine dielectric withstand test HIPOT This service note applies to instruments within the serial number range of 2814A00105 2814A00108 If you own an HP 86792A within the serial number range listed you may return it to your nearest HP Customer Service Center for the HIPOT
23. Monday through Friday between 9 a m and 5 p m for assistance Same day shipping Your order will ship within 24 hours of your verbal p o Overnight delivery Available for a nominal fee 30 day money back guarantee If you re not completely satisfied we ll refund your money To order any of the products with the fast ship icon call 800 538 HP DIRECT 800 538 8787 8787 WWW HPARCHIVE COM At HP DIRECT We Took Something Out Of Our T amp M Instruments The Wait When you know what you need and you need it ASAP call our dedicated toll free number between 9 a m and 5 p m your time Knowledgeable sales consultants are standing by ready to take your order and ship it out the very same day at no additional charge And get it to you within seven business days If that s not fast enough we can arrange for overnight delivery We re in stock 99 7 of the time HP DIRE CT What are you waiting for Send in this card for your free HP DIRECT nstruments Now catalog Start getting the same quality Hewlett Packard instruments and basic test equipment you re used to only faster 800 538 87 87 Send to Name Mr Ms Dr Rush Me A Free HP DIRECT i ess ompany__ __ SCD pt Bdg Maaiil Stop Instruments Now Catalog Address C Add me to your mailing list and send me an City State Zip HP DIRECT Instruments Now catalog right away Telephone _ Ext Tell us about yourself Number of people at your business loca
24. available to upgrade the instrument to Option K 74 023 MR 8561A 23 Modification to prevent the display intensity from dimming intermittently 023 MA 8561B 01B New firmware upgrade kit is available 020 MA 8561B 01 Firmware upgrade kit 017 MA 8561B 02 Modifications required when replacing ASCR401 PIN diode 019 MR _ 8561B 03 Electrolytic capacitor changes on the A16 Cal oscillator assemblies 019 MR 8561B 04 Rec Mod to A14 to stabilize the 10 V reference 023 14 BENCH BRIEFS WWW HPARCHIVE COM 2ND QUARTER 1990 SN Type IO MR MR MR MA MA MR MR MA MA IO IO IO MR MR MA MA MR MR MR MR MA MR MR MA MR MA MA MR MA IO IO IO MR MR MA MA MR MR MR MR MA MR MR MA MR MA SN No 8561B 06 8561B 07 8561B 09 8561B 10 8562A 02D 8562A 05A 8562A 27A 8562A 27B 8562A 27 8562A 31 8562A 33 8562A 35 8562A 38 8562A 39 8562A 40 8562A 42A 8562A 42 8562A 43A 8562A 43 8562A 45 8562A 46 8562A 48 8562A 51 8562A 52 8562A 53 8562A 54 8562B 01D 8562B 04A 8562B 26 8562B 29 8562B 31 8562B 33 8562B 35 8562B 36 8562B 37 8562B 39A 8562B 39 8562B 40A 8562B 40 8562B 42 8562B 43 8562B 46 8562B 49 8562B 50 8562B 51 8562B 52 8563A 02 2ND QUARTER 1990 Abstract Service Note Package Oven controlled crystal oscillator retrofit kit is available 020 Mod to correct intermittent connector to oven controlled oscillator 020 Recommended replacement of the A12 RF switch for improved reliabilit
25. cedure for POD cable connectors J1 J5 HP P N 1251 8158 017 MR 3314A 03 Mod to correct improperly crimped cooling fan power leads 020 IO 3562A 11 Instructions on how to service the HP 3562A Signal Analyzer with Option 063 019 MR 3563A 01 Modification prevents instrument lock up when using systhesis table 022 IO 3577A 14 Required modification when replacing U13 on the A1 board 022 MA 3586A B C 13 Modification available when replacing U1 and U29 on A61 board 023 IO 3586A B C 14 Instructions on removing the internal Ni cad battery for extended storage 023 SA 3588A 01 S Notification that the fuse label contains the wrong replacement fuse information 022 MR 3588A 02 Metal flakes settling on the motherboard may cause intermittent H W errors 022 IO 3708A 17 Semi automatic performance test for the HP 3708A 017 IO 3708A 18 Preferred repl for capacitor A501C5 on the power supply high current assy 019 IO 3708A 19 Preferred replacement for D A Converter A204U7 on the Var Gain Cntl Assy 021 IO 3709B 04 Preferred repl for the Mod Scheme Switch A3S2 on the microprocessor assy 019 IO 3746A 34A Preferred repl for the Fract N cir A30U16 on the Fract N divided by N assy 017 IO 3746A 35 Changes to the 3 1 kHz channel filter adjustment 017 IO 3746A 36 Preferred repl for the 50 MHz crystal A40Y90 on the A40 Frequency Ref Assy 019 IO 3776A 36 Preferred repl of transistors A7Q21 and A7Q22 019 IO 3776A 37 Preferred replacement of A3U33 and A204U47 021 IO 3776B
26. e assy 021 MR _ 70906B 06 2nd converter phase lock loop align adj seq is modified in S W rev A 03 00 018 IO 70907A 03A Replacement for obsolete attenuators 021 IO 70907A 03 Recomended replacement for obsolete attenuators 018 IO 70908A 01 Recommended replacement of the RF converter HP P N 5086 7737 017 IO 70908A 02A Identification of correct connector used with A1 LO leveling amplifier 020 MR 70908A 08 Module verification software modification 021 MR 85081A 01 Instructions for replacing faulty locking knobs 022 MR 85082A 01 Instructions for replacing faulty locking knobs 022 MR 85620A 01 Firmware update kit for the HP 8562A B 019 MA 85620A 02 Firmware upgrade kit 017 SA 85620A 03 S A1BT1 batteries may leak 019 MA 85629A 01C Modification available to upgrade the ROM 023 MA 85629A 07B Modification to upgrade an HP 85629A to an HP 85629B 019 IO 85629A 08 Rec method for perf LO distrib amp adj with 85629A B Test amp Adj Modules 018 MR 85629B 01A Mod to update test amp adj modules to test later ver of port SA assys 020 MR 85629B 01 Updating test and adj modules to Test Later versions of portable spect assys 017 MA 85629B 02B Firmware ROM upgrade kit 017 IO 85629B 04 Rec method for perf LO distrib amp adj with 85629A B Test amp Adj Modules 018 MR 85640A 01 Mod to prevent the tracking gen from blowing line fuse in 220V 240V oper 017 MR 85640A 03 Recommended replacement for the 230 V line fuse 023 MR 85685A 21 New ROM repl
27. e the 10 V reference 023 IO 8560A 07 Oven controlled crystal oscillator retrofit kit is available 020 MR 8560A 08 Mod to correct intermittent connector to oven controlled oscillator 020 MR 8560A 10 Modification to prevent the display intensity from dimming intermittently 023 IO 8561A 02 Availability of a new temperature controlled crystal oscillator 018 IO 8561A 05 Recommended replacement for obsolete second converter 017 MR _ 8561A 06 Modification to prevent intensity offset failure caused by parasitic oscillations 018 MR 8561A 07 Modification to reduce baseband noise when using 08562 60094 power supply assy 018 MR 8561A 09A Mod to update test amp adj modules to test later ver of port SA assys 020 MR 8561A 09 Updating test and adj modules to Test Later versions of portable spect assys 017 MR 8561A 11 Modification to eliminate 1 8 MHz sampler buffer oscillation at high temperatures 017 MR _ 8561A 12 Modification to prevent the divide by two circuit from providing erroneous results 017 MR 8561A 13 Electrolytic capacitor changes on the A16 Cal oscillator assemblies 019 MA 8561A 15 Modifications required when replacing ASCR401 PIN diode 019 MR 8561A 16 Rec Mod to A14 to stabilize the 10 V reference 023 MA 8561A 18 New ROM upgrade kit is available 020 MR _ 8561A 20 Mod to correct intermittent connector to oven controlled oscillator 020 MR 8561A 21 Recommended replacement of the A12 RF switch for improved reliability 023 MA 8561A 22 Modification
28. easy to find the instruments you need Full product descriptions photographs flow charts specifications compatibility and selection guides help you choose the best models for your application The Instruments Now catalog even includes new HP products which may not be available in other HP catalogs HP DIRECT 800 538 8787 Our Stock Answer Is Yes NO POSTAGE NECESSARY IF MAILED IN THE UNITED STATES TARR TE DATA TNT es BUSINESS REPLY MAIL seamen FIRST CLASS MAIL PERMIT NO 1478 SUNNYVALE CA wae pee EE ie r POSTAGE WILL BE PAID BY ADDRESSEE 2 AS TM ETA eT Hewlett Packard Company E HP DIRECT PO Box 611298 San Jose CA 95116 9890 WWW HPARCHIVE COM SN SN Abstract Service Note Type No Package MA 436A 16B Recommended replacement display driver assembly 017 MR 437B 03 Modification to prevent erroneous power meter readings 019 MR 437B 04 Mod to overvoltage protection circuit 020 MR 438A 10 Recommended A4C14 and A4C16 capacitor replacement to improve performance 017 IO 1630A D G 14 Display system components available as a matched set 2090 0227 021 IO 1631A D G 14 Display system components available as a matched set 2090 0227 021 IO 1650A 09 Repair procedure for POD cable connectors J1 J5 HP P N 1251 8158 017 IO 1650B 01 Repair procedure for POD cable connectors J1 J5 HP P N 1251 8158 017 IO 1651A 09 Repair procedure for POD cable connectors J1 J5 HP P N 1251 8158 017 IO 1651B 01 Repair pro
29. ens e g 1234 001 and 1234A E12 Where space is limited option numbers may be shortened to less than three charac ters e g 1234A 01 02 EI2 Model numbers are arranged in typi cal computer sequence i e left jus tified alpha numeric sequence so that all the 1s Model 1 11 111 1111 etc are listed before the 2s Model 2 22 2222 etc The Hewlett Packard office nearest you will be pleased to work with you on procurement matters Also note that the most currently produced HP products are on GSA federal supply schedule multi award contracts and that GSA catalogs are available from your HP office To order your Logistics Data Book specify publication no 5954 7744 Logistics Data Book 1990 Cross References of HP Model Numbers to NSN and JET Ds Inchalas Proviatonis Data and Recommen MENES If you have any comments or sugges tions about how we can make the Logistics Data Book more useful to you please let us know by writing to Hewlett Packard Co U S Field Operations John Cloutier 19320 Pruneridge Avenue Cupertino CA 95014 o What is Traceability and How Does It Relate to Calibration Uncertainty Jim Bechtold Hewlett Packard Traceability is proof that measure ments can be attributed to a national standard The process involves the tracing of measurement compari sons made between the instrument used and the national laboratory Technically traceabi
30. f A12 YIG driver board assy or A12W1 MSIB cable assy 021 IO 70601A 02A Replacement for obsolete attenuators 021 IO 70601A 02 Recommended replacement for obsolete attenuators 018 MR 70601A 05 Recommended modification to the module verification software 020 MR _ 70700A 02 HP 70700A performance software modification to Rev A 00 00 019 MR 70700A 03 Mod to correct power up sequence failure 020 IO 70700A 04 1 MHz and 10 MHz low pass filters required for performance tests 023 MR 70810A 01A Firmware upgrade kit 017 MR 70810A 01B New firmware upgrade kit corrects firmware problems 020 IO 70900A 14D Firmware history showing compatibility 017 IO 70900A 14E 70900A compatability requirements when used with diff spect anal systems 019 IO 70900A 21 Verification software mod to prevent ERROR 18 during enhanced inverse video 017 IO 70900A 22 Repl screws for A6A3 idler buffer assembly 019 MR 70900A 23 HP 70900A module verification software modifications to Rev A 03 00 019 MR 70900A 24 Mod to correct 5 2 volt power supply 020 MR 70900A 25 Mod to correct FFS handshake error 020 IO 70900B 01 70900B compatability requirements when used with diff spect anal systems 019 MR 70902A 03A Module verif S W changes eliminate errors when performing module gain adj 018 IO 70902A 04 Recommended replacements for A1 A2 and A3 board assemblies 017 IO 70902A 05 Procedure for replacing matched crystals and A1 or A2 board assemblies 017 MA 70903A 01 Availability of linear AGC
31. he op amp By applying Kirchhoff s current law the algebraic Input Component sum of the currents toward any point in a network is zero to the inverting input terminal of the op amp it can be seen that the input current must be equal and opposite to the feedback current Extensive use will be made of this important result I lin The Equivalent Circuit The schematic diagram of the op amp with negative feedback may be simplified using the previous results to the equivalent circuit shown in Figure 4 The equivalent circuit is ob tained by recalling that Ij is equal and opposite to Ipg and so Figure 3 can be relabeled as shown in Figure 4 Since Vy is nearly zero the inverting input of the op amp can be considered to be at ground potential This simplifies the diagram of Figure 4 to the important equivalent circuit shown in Figure 5 The equivalent circuit shown in Figure 5 shows why op amps with negative feedback are so useful The input circuit is electrically isolated from the output circuit yet the cur rent flowing through the input com If Vin were actually equal to zero the output of the op amp would also be zero and the op amp would be useless In reality Vy is a very small voltage usually less than a millivolt But for the purpose of calculating input and feed back currents very little error is introduced by approximating Vj as equal to zero Feedback Component Figure 4 Negati
32. he wrong replacement fuse information 022 Modification to prevent self test failure in large system installations 019 Instructions for mating Option 001 to fiber optic cable with ST connectors 017 Installation of fiber optic interface upgrades 022 Instructions for mating Option 001 002 to fiber optic cable with ST connectors 017 Repair procedure for intermittent loss of signal sensing 020 Modification to make the HP 42851A compatible with the HP 4285A 022 Vertical gain calibration procedure into 50 ohms 021 Vertical gain calibration procedure into 50 ohms 021 A2 CPU assembly replacement requires mod or repl of A3 Horiz Cntl Assy 017 System compatibility and upgrades 021 List of 54120 Digitizing Oscilloscope system compatibility and upgrades 019 TDR system specification change 021 1 specification change in the 54121A TDR System 019 Manul chng load default service routines 6 7 amp 8 before doing H W adjmnts 019 Display system components available as a matched set 2090 0227 021 Replace firmware to correct bugs 017 New test procedure improves voltage measurement accuracy test 019 Replacing cabinet requires a new rear panel 020 New test procedure improves voltage measurement accuracy test 019 Replacing cabinet requires a new rear panel 021 WWW HPARCHIVE COM BENCH BRIEFS 17 SN SN Abstract Service Note Type No Package MR 60501A 01 Rec addition of a 0 5 amp fuse to protect the bias transformer circuit 019 IO 60501A 02 Oper inst
33. iability 017 Modification to correct power transformer wiring 019 Strap handle may break while carrying the instrument 019 Remove unsafe carrying straps and use caution with customer furnished straps 020 Modification to improve power supply relay reliability 017 Modification to correct power transformer wiring 019 Strap handle may break while carrying the instrument 019 Remove unsafe carrying straps and use caution with customer furnished straps 020 5 2 volt power supply modification 021 Instructions for retrofitting HP 5361A to HP 5361B 022 Mod to prevent intermittent HP IB hang up 020 Mod to prevent time interval miscount in the divide by 10 mode 021 Modification to install Firmware Revision 3018 Upgrade kit 023 Modification to ensure operation of the oven oscillator in standby mode 017 Instruction sheet for the HP 5372A Support Service Kit P N 05372 67001 019 Instructions for installing firmware revision 2947 retrofit kit P N 05372 67003 019 Oper inst amp procedures when using the EMPRO current shunts for calibration 019 Modification to reduce source turn on current overshoot 022 Modification to reduce source turn on current overshoot 022 WWW HPARCHIVE COM BENCH BRIEFS 13 SN SN Abstract Service Note Type No Package IO 6129C 05 Rec repl for the A13Q2 A14Q2 A15Q2 and or A16Q2 transistors 019 IO 6130C 05 Rec repl for the A13Q2 A14Q2 A15Q2 and or A16Q2 transistors 019 IO 6131C 05 Rec repl for the A13Q2 A14Q2 A15Q2 and or A
34. kit to correct 3 dB amplitude accuracy error at 2 GHz 019 IO 86790A 01 How to use the internal DSA capabilities to isolate faults 020 MA 86792A 01A Firmware history and upgrade procedures 020 SA 86792A 02 S Instructions for performing routine dielectric withstand test HIPOT 017 IO 86792A 03 Method of using internal firmware and diag routines to adj det offset amp gain 021 IO 86792A 04 How to adjust 268 MHz step switch assembly for best 4 2 spur response 023 Service Note Types IO Information Only MA Modification Available MR Modification Recommended SA Safety PR Priority Safety 2ND QUARTER 1990 BENCH BRIEFS 19 WWW HPARCHIVE COM Service Tip Extend the Life of Your CRT Cathode ray tubes are expensive com ponents of your HP instrument therefore it is in your best interest to extend the life of your CRT as long as possible New Product Turn On Before you turn on your product for the first time turn the intensity to the off position Allow the CRT to warm up and the product s power supplies to stabilize for at least 30 minutes before turning the intensity up to a comfortable viewing level Extending Life Most CRTs have an expected lifetime of 10 000 hours At 2 000 hours per year five years of CRT life could be expected 8 hours day x 5 days week x 50 weeks If you leave the CRT on for two shifts per day 2 5 years could be expected To maximize the CRT lifetime HP recommends turning the CRT filament off when
35. lity involves the ability to quantify the measurement errors present in the test or measure ment process in terms of the national standards Agencies require us to ob jectively demonstrate that traceability exists Usually through a series of re ports attesting to the calibration of the instruments used in a test situation 8 BENCH BRIEFS the standards used to calibrate these standards and so on back to the re ports issued by national laboratory standards Calibration uncertainty is the ability to quantify the error sources present in the calibration measurement Knowing that the act of making mea surements is experimental there have to be some guidelines that tell the person doing the measurement that the job is being performed satis factorily A rule of thumb method called the accuracy ratio is used in many laboratories to determine whether the uncertainty is reason WWW HPARCHIVE COM able The desired ratio of accuracy be tween a source instrument and one to be calibrated is 10 1 If this cannot be met it is permissible to reduce the ratio downward to a lower limit of 4 1 This ratio is calculated by dividing the tolerance of the measurement to be made e g 5 by the tolerance as signed to the instrument used to make the measurement e g 1 In this example of accuracy the ratio would be 5 1 In some of today s instrumentation the instrument being calibrated is al most as accurate as the sou
36. ng input If an input signal is applied to the input with input grounded the polarity of the output signal will be opposite to that of the input signal If an input signal is applied to the input with the in put grounded the polarity of the out put signal will be the same as that of the input signal For an ac signal this means that the output of the op amp will be 180 degrees out of phase with a signal applied to the input but in phase with a signal applied to the input WWW HPARCHIVE COM bilite SERVICE INFORMATION FROM HEWLETT PACKARD 2nd Quarter 1990 Ideal Op Amps With Negative Feedback The most common op amp circuit con figuration uses two external compo nents 1 an input component and 2 a feedback component see Figure 3 When the feedback component is be tween the op amp output and the input the circuit is said to have negative feedback When the feed Power Supply Fig 2a Detailed schematic te Fig 2b Simplified schematic Figure 2 Op amp schematic symbols Hewlett Packard 1990 Input Component Feedback Figure 3 Op amp circuit with negative feedback back component is between the op amp output and the input the cir cuit is said to have positive feedback In Figure 3 an op amp is shown with negative feedback Ern is the inut sig nal Vij is the differential input to the op amp and Eo is the op amp output The open loop gain is defined as the
37. o strap or other carrying appliance should be con nected at these points Please remove the non adjustable strap from the unit and return it to the following address A new adjust able strap will be returned to you in addition to a pair of plastic plugs to block the front panel carrying strap attachment holes Joe Dore 52U 19 Hewlett Packard Co 5301 Stevens Creek Blvd Santa Clara CA 95052 8059 The solution to making the instru ment portable is the design of a soft carrying case This case has been de signed to enhance portability with tough cordura nylon double stitched construction that is padded on all six sides The permanently attached ad justable strap provides a much safer means of carrying the product and al lows easy measurements with the unit suspended from the shoulder If you originally purchased the prod uct with the Option 060 portability op tion and have returned the strap as previously requested you will receive this new soft carrying case at no charge If you did not order Option 060 and wish to buy the soft carrying case order HP P N 05348 60214 The price is 295 U S list For those customers ordering the in strument and specifying the portabil ity option please be advised that Op tion 060 has been discontinued The portability option is now the soft car rying case and is listed as Option 070 295 U S list 2ND QUARTER 1990 HP 8340A B Synthesized Sweepers HP 8341A B Synthesi
38. other 250 microvolts of error or 25 ppm These two elements alone constitute an error of 50 ppm or 0 005 Note that the obvious way to avoid these errors is to use 4 wire remote sensing whenever the load is less than 1 megohm Random Errors These errors are indicated as a scatter about an average when a multiple number of measurements are taken This can be the result of variations in the measuring system or changes in Random uncertainties are of a type that lend themselves to statistical analysis since they can be considered to vary either positively or negatively around the measured value They are due to totally unknown causes and are detectable when repeated mea surements are made with a seemingly constant set up and consistent technique by the user An example may be a variation in im pedance matching in high frequency instruments due to changes in charac teristics when the lead connectors are removed and replaced This may be due to the wear or contamination of BNC connectors which are quite sus ceptible to this behavior When a succession of measurements are made which differ one from tions can be made regarding random errors The closest value to the true value is the mean value It is likely that values close to the mean value will be more numerous than values that are far away from the mean value There are likely to be as many read ings that lie above the mean value as there are those
39. r the control of the individual totally separate from the instrumentation Example of gross errors are Misreading the instruments Making an incorrect adjustment Applying instruments improperly Computational errors Recording interpolated data As can be seen these are errors that can be avoided by care and attention WWW HPARCHIVE COM Figure 1 Reading of Meter 1 Figure 2 Reading of Meter 2 Figure 3 Altered Reading of Meter 1 Systematic Errors Systematic errors relate to the in strumentation or external influences to the instruments Systematic errors cause the measured value to be offset by a fixed amount as contrasted to random errors which are bipolar in nature One example may be loading All measuring systems are intrusive That is no matter what type of device is used to make a measurement it will have some effect on the system being measured Consider the fact that no voltage source has the ideal zero impedance and no current source has the ideal infinite impedance A voltage source may have a source resistance of as little as 0 01 ohm and the ability to supply current of 25 mil BENCH BRIEFS 9 liamps at 10 volts output The internal voltage drop could then be 250 micro volts which represents 25 ppm of the 10 volt output 0 0025 In addition assume that the connecting leads have 10 milliohms of resistance The voltage drop across the leads would add an
40. ratio of Eo to Vin E Open Loop Gain IN The closed loop gain is defined as the ratio of Eo to Ew E Closed Loop Gain Ein The open loop gain is the gain of the op amp and this gain is independent of the input and feedback compo nents The closed loop gain how ever depends only on the values of the input and feedback components when the closed loop gain of the cir cuit is much less than the large open loop gain of the op amp Input Current and Feedback Current When an input signal Eyn is applied to the circuit of Figure 3 a current Im flows through the input compo nent and a voltage Vm develops across the input terminals of the op amp The very high gain op amp 2 BENCH BRIEFS amplifies the differential input vol tage Vix producing an output vol tage Eo with a polarity opposite to that of Vix This output is fed back through the feedback component and opposes the input voltage that pro duced it Because the negative feedback signal opposes the input signal V y is very small Therefore the higher the gain of the op amp the smaller is Vn In fact for some calculations Vyn can be assumed equal to zero and the invert ing input at virtually the same poten tial as the noninverting input The relationship between the input current In and the feedback current Iks is most important Assuming that Vj is equal to zero it follows from Ohm s law that no current can flow into t
41. rce device 2ND QUARTER 1990 and therefore at a ratio of less than 4 1 In this situation the method of calibration used is called enhanced accuracy calibration To achieve en hanced accuracy it is necessary to utilize a higher echelon standard dur ing the calibration process This will provide as much as another order of magnitude to the source equipment which widens the ratio between the two instruments to maintain a good confidence level We recommend that when you get below 4 1 contact your metrologist for advice A more specific method of determin ing uncertainty involves understand ing the types of errors that exist dur ing measurement and calibration and ways of avoiding the most serious ones But before we get into the three types of errors we should define two terms used in measurement that are quite often confused accuracy and precision Accuracy The accuracy of a measurement is an expression of the closeness of its re sult to the true value A high accuracy indicates a close approach to the true value Precision The precision of a measurement is a measure of its repeatability A high precision indicates the ability to re peat measurements within narrow limits These two definitions form the basis for everything else that follows rela tive to measurement and calibration The ultimate goal is to achieve both accuracy and precision in every mea surement and in every calibration To
42. rn it to your nearest HP Customer Service Center for the HIPOT test which will be conducted free of charge HP 5347A amp 5348A Counter Power Meters Safety Service Notes 5347A 02 S and 5348A 02 S describe an incorrectly manufactured power transformer The serial numbers affected are 2924A00101 158 and 160 170 for the HP 5347 and 2924A00101 120 for the HP 5348 The manufacturing error concerns the transformer primary WWW HPARCHIVE COM wires being improperly connected in side the transformer The result is that when operating on the 220 volt line setting the line fuse blows Both the line module and power transformer must be replaced at an HP Customer Service Center Do not attempt to re wire the transformer as this will in validate the color coding used on the wires Safety Service Notes 5347A 03A S and 5348A 03A S concern the re moval of unsafe carrying straps This service note applies to all units The clips on the ends of the carrying straps which are part of Option 060 are defective and may fail in the nor mal use of the instrument Damage to the instrument and or injury to per sonnel may occur The defective straps are identifiable as being non ad justable in length Also there is con 2ND QUARTER 1990 cern over the strength of the front panel casting at the carrying strap holes Mis application of a customer furnished strap may apply sufficient leverage by weight of the instrument to cause breakage N
43. s connected into the feedback path as shown in Figure 15 Eyn versus Eo follows a nonlinear function The base emitter junction of Q4 represents the logarithmic element in the feed back loop 2ND QUARTER 1990 Figure 13 Simple integrating operational amplifier The Antilog Op Amp By placing the nonlinear element in the input path as shown in Figure 16 the circuit becomes an antilog conver ter For a logarithmic input Em the output Eo will be a linear signal Multiplication Division With eC Log Antilog Operational Amplifiers Figure 14 Simple differentiator operational amplifier Since log A log B log AB and log A log B log A B a circuit using two log converters and a sum ming subtracting amplifier fol lowed by an antilog converter will output the product or the division of the two input signals Figure 17 illus Figure 15 Simple logarithmic converter Figure 16 Simple antilog op amp trates the circuit for multiplication operational amplifier Figure 17 Multiplication circuit using log and antilog operational amplifiers 2ND QUARTER 1990 WWW HPARCHIVE COM BENCH BRIEFS 5 TUNE CONTROL POWER SUPPLY VOLT ADJ Figure 18 Typical op amp application as an impedance converter Us isolator U and summing amplifier U Typical Op Amp Circuit Figure 18 illustrates a typical example op amp application The task is to pro duce and mix a tuning voltage with a s
44. tion Which electronic test instrument do you use specify buy 00 O I use these products in my job 010 1 49 04 O 500 999 HP Non HP 03 O lam a purchasing agent 02 O 50 249 05 O 1000 00150 A015 O DVM DMMs 03 O 250 499 0016 O A016 O Counters 00170 A017 O Oscilloscopes Check the department AND title which closest describe your position 0018 O A018 O Pulse Function Generators Department Title 0019 O A019 O Power Supplies 20 O Engineering 08 D Electronic Engineer oe 5 Het 2 ia i 20 O R amp D OA O Mechanical Engineer para esea duit 20 C Test 02 C Technical Staff 0020 O A020 C Microprocessor Development Systems AO C Quality Assurance 07 C Technician 00130 A013 C Component and Semiconductor Analyzers 10 E Manufacturing 0B E Technical Supervisor Manager ro z so ee 7 ice baie Testers 40 O Purchasing OC C Purchasing Agent Buyer aa Stace 50 O Service 0D O Administrative Manager or Pie ai ower Meters 90 Data Processing 05 C Owner Principal wi bration Anazers BO O Education OE C Programmer 0004 O A004 O Data Acquisition and Control O Other OF O Educator 0021 O A021 O X Y and Strip Chart Recorders ther 00230 A023 O Other WWW HPARCHIVE COM TP03 Instruments Now Takes The Wait Out Of Basic T amp M Orders The next time you need basic test and measurement prod ucts in a hurry reach for an Instruments Now catalog Complete product pricing and ordering information at your fingertips Prod uct number and alphabetical indexes make it quick and
45. ve feedback op amp circuit with equivalent feedback current shown WWW HPARCHIVE COM 2ND QUARTER 1990 9 Figure 5 Equivalent circuit of Figure 4 ponent dictates what current must flow through the feedback compo nent By choosing different input and feedback components different cir cuit functions can be performed The circuit functions listed in Table 1 will be discussed later in this article Figure 6 Simple voltage divider Figures 6 and 7 illustrate a very simple concept in conjunction with an op amp The potentiometer P is used as a variable voltage divider and the vol tage delivered to the load is in a linear ratio with the shaft rotation This will only be the case if the load is an infi nite resistance or is very high in com parison to the resistance of P As an example if P and the load are each 10 kilohms and P is set at 50 percent the division ratio will not be 1 2 but 2 5 as shown in Figure 7 If an op amp is connected between the movable contact of P and the load as shown in Figure 8 the op amp will provide perfect isolation The op amp must have a closed loop gain of one This is possible with a 100 percent 2ND QUARTER 1990 ae Table 1 Table of Circuit Functions Figure 7 Simple voltage divider set at 50 percent feedback An op amp connected in this way is often referred to as a voltage follower or an impedance converter An additional characteristic that is im portant for
46. virtual ground there can be no current flowing over A from one input into another input The total input current is I I The number of inputs is only limited by practical considerations The Differential Subtracting Op Amp If the same signal is applied to both the input and the input of the op amp shown in Figure 12 the two amplified output signals will be 180 degrees out of phase and will com pletely cancel each other Since the op amp responds only to differences between its two inputs it is said to be a differential amplifier The voltage difference between the input and the input is called the differential input voltage Since a differential amplifier amplifies only the differen tial input voltage and is unaffected by signals common to both inputs it is said to have common mode rejection Common mode rejection can be very useful for example when measuring 4 BENCH BRIEFS GAIN FOR E 2 11 R GAIN FOR E oa 12 GAIN FOR E 5 13 R2 R2 R2 E Boe Ess E R4 Ryo Ra Figure 11 Simple summing operational amplifier small signals in the presence of 60 Hertz noise The 60 Hertz noise com mon to both inputs is rejected and the op amp amplifies only the small signal difference between the two inputs Note that an ideal differential op amp produces neither a differential mode nor a common mode output in re sponse to a common mode interfer ence input The Integrating Op Amp
47. weep ramp for a YIG oscillator U operates as an impedance converter for the zener diode CR Rioo pro duces the tuning voltage that is iso lated by Uz Finally U operates as a Roy 10K SWEEP TUNE summing amplifier for the tuning and sweep voltage If you desire a more detailed and in depth discussion of op amps I suggest that you read Understanding IC Operational Amplifiers by Roger Melen and Harry Garland available from Howard W Sams amp Co Oo Safety Related Service Notes Service notes from HP relating to per sonal safety and possible equipment damage are of vital importance to our customers To make you more aware of these important notes they are printed on paper with a red border and the service note number has an S suffix In order to make you im mediately aware of any potential safety problems we are highlighting safety related service notes here with a brief description of each problem Also in order to draw your attention to safety related service notes in the service note index each appropriate safety related service note is high lighted with a contrasting color HP E2500 Frequency Agile Signal Simulator Safety Service Note E2500A 01 S de scribes how to safety check the 6 BENCH BRIEFS routine dielectric withstand test HIPOT This service note applies to instruments within the serial number range of 2845A00101 2935A00114 If you own one of these HP E2500As you may retu
48. y 023 Modification to prevent the display intensity from dimming intermittently 023 ROM upgrade kit is available 020 Modification to reduce 80 kHz power supply sidebands 017 Modification to eliminate display flicker 019 Modification to eliminate display flicker 022 Modification to eliminate display flicker 017 Bypass capacitor added to A15 assembly to improve residual responses 019 Availability of a new temperature controlled crystal oscillator 018 A new A12 RF switch is available for instruments without Option 026 017 Recommended replacement for obsolete second converter 017 Modification to prevent intensity offset failure caused by parasitic oscillations 018 Modification to reduce baseband noise when using 08562 60094 power supply assy 018 Modification available to install dc protection in the Low Band Input 023 Mod to add dc blocking capacitor in the low band input 020 Mod to update test amp adj modules to test later ver of port SA assys 020 Updating test and adj modules to Test Later versions of portable spect assys 017 Modification to eliminate 1 8 MHz sampler buffer oscillation at high temperatures 017 Electrolytic capacitor changes on the A16 Cal oscillator assemblies 019 Modifications required when replacing ASCR401 PIN diode 019 Rec Mod to A14 to stabilize the 10 V reference 023 Mod to correct intermittent connector to oven controlled oscillator 020 Modification available to upgrade the instrument to Option K 74 023 Modification
49. zed Sweepers HP 8719A Network Analyzers HP 8720A B Network Analyzers The following Safety Service Notes describe possible injury from falling instruments due to damaged front panel handles 8720A 05 S 8720B 01 S 8719A 01 S 8340A 30 S 8340B 30 S 8341A 30 S 8341B 30 S If damaged handles are used to lift or support the instrument the handles will break causing the instrument to fall possibly resulting in personal in jury Exercise caution when using the front handles to lift the instrument The damaged handles will be re placed at an HP Customer Service Center or you may order the front handle replacement kit free of charge HP P N 5062 3990 and perform the replacement following the instruc tions in the product s service manual HP 8657B Synthesized Signal Generator Safety Service Note 8657B 01 S de scribes a possible shock hazard that may exist if the instrument s toroidal mains transformer s insulation has been damaged by the A14 assembly s heatsink The units affected are within the following serial number ranges 2935U00470 2935U00543 2948U00544 2948U00576 2949U00577 2949U00585 The HP 8657B may present a shock hazard only if the following condi tions exists The mains transformer has not been manufactured by NUVOTEM and The A14 heatsink has damaged the WWW HPARCHIVE COM mains transformer s insulation If your instrument is one of the above please return the unit to an HP
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