Fluke PM6681 Service Manual Download Page 33

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Summary of Contents for PM6681

Page 1: ...Timer Counter Analyzers PM6681 PM6681R PM6681R 676 AF Service Manual...

Page 2: ...r the U S Government to reproduce copies ofthis manual on the condition that the legend Reproduced with Permis sion be legibly displayed on the copies This material is not for resale It is limited to...

Page 3: ...cuit board Unit 1 has recently been redesigned due to obsolescence of a number of integrated circuits Designa tions found in circuit descriptions schematic diagrams and parts lists in the first eight...

Page 4: ...This page is intentionaliy ieft biank IV...

Page 5: ...0 or PM 9691 Oven Oscillator 3 4 Reinstalling the Battery 3 4 Exchange Procedure 3 4 4 Circuit Descriptions Block Diagram Description 4 2 General 4 2 Hardware Functional Description 4 4 Front Unit 4 4...

Page 6: ...6 4 Interpolator 6 5 Input Amplifier 6 6 Step Response 6 6 Channel A 6 6 Channel B 6 6 IX Attenuator channel A 6 6 1 0X Attenuator channel A 6 7 IX Attenuator channel B 6 7 1 0X Attenuator channel B 6...

Page 7: ...Chapter 1 Safety Instructions...

Page 8: ...ment in a safe condition WARNING The opening of covers or removal of parts except those to which access can be gained by hand is likely to expose live parts and accessible terminals which can cause d...

Page 9: ...Chapter 2 Performance Check...

Page 10: ...with probes 350 MHz PM3295 Power Supply min 40 Vdc PM2811 113 PE1537 PE1542 BNC cables 5 to 7 cables Table 2 1 Recommended Test Equipment This test equipment in needed if an option Is installed Prepar...

Page 11: ...8 V Enter ENTER AC DC AC 1X 10X 10X COMA COMA HOLD OFF ON HOLD OFF HOLD OFF SET HOf f ti PRESET II Other II TIME 200 s SELECT A 500 s ENTER HOLD DISPL HOLD HOLD SINGLE SINGLE FUNCTION VOLTAmax MIN FUN...

Page 12: ...nnel B Repeat the measurements for B as described above Trigger indicators and Controis NOTE This test must be performed in the sequence given Press the PRESET key to set the Timer Counter in the defa...

Page 13: ...able 2 7 Acceptance test for oscillators Resolution Test Connect a pulse generator to a power splitter Connect one side of the power splitter to the A input of the counter via a coaxial cable Connect...

Page 14: ...lloscope to check the signal at Probe Comp View at the rear The square wave will have the same step response and 4 Vpp amplitude Select XI 0 attenuation Check that the square wave is 2 kHz and 0 4 Vpp...

Page 15: ...sine wave in accordance with the correspon ding table below Frequency Amplitude Pass Fail MHz mVpiv ip dBm 70 900 10 27 1100 15 23 1300 40 15 Table 2 11 Sensitivity of PM 9621 PM 9624 PM 9625B or PM...

Page 16: ...This page is intentionaily ieft blank 2 8 Performance Check Options...

Page 17: ...l il PRESET SELECT A ENTER HOLD HOLD W SINGLE EUNCTldN I FUNCTION V RESTART PRESET ENTER STARTARfi i ggESpV iSTOPARWl RESTART PRESET CHECK Other Preset m V SiNGLE WoLTAMk m V RfSE FALLA VOLTA MAX MiN...

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Page 19: ...enuation olfl ii iiETB 0 0 V blinking fe Attenuation blinking 1 Reference Oscillators Oscillator readout value iStalidardi il0 t 0000000 tUlHz fcjSiisO iz PIM 9678B lilStft PM 9690 04 10 00000d00 MH P...

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Page 21: ...Chapter 3 Disassembly...

Page 22: ...G When you remove the cover you will expose live parts and accessible termi nals which can cause death WARNING Although the power switch is in the off position line voltage is present on the printed c...

Page 23: ...the counter Disconnect the cable from the mini coax connector A on the HF input Press the clips B apart and lift the HF input pea straight up and out When installing the HF input make sure that the c...

Page 24: ...the metal clip and press the battery towards the front of the counter using a screwdriver Reinstalling the Battery The instrument will lose its stored programs and front panel settings when the batte...

Page 25: ...Chapter 4 Circuit Descriptions...

Page 26: ...e user communication A flat cable connects the front unit to the main board unit and the molded front piece screws onto the two aluminum profiles Most functions such as the following are placed on the...

Page 27: ...Block Diagram Description 4 3...

Page 28: ...s to the p controller on the main board R201 sets the clock frequen cy of the drivers to approximately 140 kHz The VLCD pin is connected to GND on the main board A back light is provided with the LCD...

Page 29: ...istor R92 immediately after the selector serves both as current limiter with the voltage limiter see below and as impedance matching resistor This resistor also im proves the V Standing Wave Ratio of...

Page 30: ...operational amplifier stage the low frequency path is fed The low frequency path handles frequencies up to approximately 5 kHz Through the FET V1 gate the high frequency signal is fed The high impedan...

Page 31: ...input si gnal is divided by a factor of about 2 4 before it reaches the comparator The counter is provided with fixed hysteresis i e it is not controllable via the front panei or GPiB Buffer Stage Bef...

Page 32: ...board it should compensate for delays in OQ0502 U58 Event Delay Also for use in the arming function the inverse output from the buffer stage V4 of channel B is used see Figure 4 10 This signal called...

Page 33: ...o prevent noi se from the digital circuitry to influence the trigger level see Figure 4 11 The trigger level circuits consists of Reference voltage circuit 2 5 V U86 Reference voltage inverter circuit...

Page 34: ...3 via the diodes D50A and D50B Every switch pulse causes a voltage drop over the resi stors R471 to R473 and R558 This voltage feeds the SEN SE input pin 5 of the control circuit U91 When the volt age...

Page 35: ...et enough current of this voltage a certain current of the regulated 5 V must be used 5 V controls the switching on off of 12 V and 7 V When 5 V is on V48 conducts and the base of VI 8 will be approxi...

Page 36: ...NODIV Figure 4 14 OQ0502 and OQ0504 block diagram the resistor R564 and then controls the fan via U99 and V62 4 12 Hardware Functional Description...

Page 37: ...erpolator OQ0502 U58 circuit includes the generation of the error pulse and the time expander OQ0504 U56 holds the measuring lo gic for the expanded pulse The small error pulse is the time from the ex...

Page 38: ...divider U85 The reason for this is that the OQ0502 can not handle frequencies above 225 MHz To be able to measure frequency bursts also on input C the si gnal from the prescaler is divided by two by...

Page 39: ...1 25 1 4285 1 6667 2 2 5 3 3333 5 10 MHz R276 R278 and D35 protect the input U88 amplifies the signal and make nice pulses out of it U37 generates short pulses which is then filtered in the crystal f...

Page 40: ...16 bits The address and data bus ADO to ADI 5 is shared time multiplexed between addresses and data Therefore the address must be stored in an address latch U14 and U15 by using the signal ALE pin 62...

Page 41: ...in put ACHO of the p controller U6 which recognizes the bo ard This makes it possible to make the software backward compatible The different prescalers are identified in a similar way R1 92 to R1 94...

Page 42: ...e internal control regi sters if U78 has a message for the microprocessor it uses the GPIB interrupt signal The address of the GPIB bus is software controlied U9 to U13 are the RAM used to execute the...

Page 43: ...NPUTS External reference input BNC D External arming input BNC E Rear panel inputs factory mounted option Power supply inlet including EMI filter OUTPUTS Internal reference output BNC G Gate open outp...

Page 44: ...ge drops of the Schottky diodes GR3 and GR4 the charging of capaci tor C4 starts Capacitor C4 filters the voltage after the Schottky diodes The PIN diodes GR11 start to conduct when the voltage is low...

Page 45: ...re behavior of the detector diode GR7 Forte sting purposes the level detection can be overruled by the signal TEST GO A high level makes TS10 conduct and that enables the ECL output signal despite the...

Page 46: ...r The amplifier consists of 4 cascade coupled integrated GaAs amplifiers each amplifies approximately 8 dB First divider The GaAs divider chip consists of an input buffer 3 divi der stages and 2 outpu...

Page 47: ...MIT or Wind ows TERMINAL EMULATOR Switch on the counter Every time the counter is switched on the following message will be displayed on the screen Code start OK Ram regs OK Timerl OK Prom banks OK Pr...

Page 48: ...This page is intentionaily ieft biank 4 24 Hardware Functional Description...

Page 49: ...Chapter 5 Repair...

Page 50: ...re stability of a TCXO or OCXO will be increased by a factor of 3 The temperature stability indicated for TCXO and stand ard oscillators are mainly dependent on the ambient tem perature When operating...

Page 51: ...of Final Value n a n a 15 min 15 min Table 5 1 after 48 hours of continuous operation Battery Replacement To preserve data and variables needed for the use of PM 6681 a lithium battery is included Th...

Page 52: ...A O bo Output voltage High VoH 4V 1 V 4 9 V 2 7 V Low VOL 3 3 V 1 7 V 0 05 V 0 4 V Bias ref voltage Vbb 3 7 V 1 3 V Table 5 2 Logical levels Required Test Equipment To be able to test the instrument...

Page 53: ...before you have checked Level 6 Text Function Level Exit test r 0 ROM test 3 Automatically test rA RAM test 3 Automatically test Core UC Kernel test 3 4 LOCAL PRESET test relay Control signal test 5...

Page 54: ...insulating transformer with separate windings Set the counter to STAND BY mode Check that the voltage between P19 and P23 is in the range of 90 to 260 Vac Check that the DC voltage between pin 1 and 4...

Page 55: ...ircuits See also Chapter 4 Circuit Descriptions Oscillator Circuits Optional Oscillator PM 9678B This test can be carried out only if the counter is equipped with an optional oscillator PM 9678B Be su...

Page 56: ...nkO 2080h zero OK 4000h zero OK Asics 0291 h 02A5h OK PHILIPS PM6681 0 MAIN X1 02 Mar 24 1994 10 30 26 GP1BX1 13 Mar 01 1994 123 P5 _ P1 0 U6 19 50t jS r J P1 1 U6 20 I ll P1 4 U6 23 HSI 1 U6 25 P1 5...

Page 57: ...e Figure 5 12 NOTE By removing R183 to R190 R209 to R212 and R221 to R224 the microcomputer kernel AD0 AD1 5 can be separated from the rest of the counter logic NOTE These resistors are located at the...

Page 58: ...AAA on the DATA ENTRY keypad Press ENTER Examine the DATA bus lines Press LOCAL PRESET Enter the data code 170 hex AA on the DATA ENTRY keypad Press ENTER Enter the address code 21845 hex 5555 on the...

Page 59: ...TE U18 is located at the bottom side of the PCA Oi P5 U18 19 U18 18 U18 17 U18 16 U18 15 U18 14 U18 13 U18 12 P8 P15 P14 P13 P12 P11 P10 P9 jS FL 250u L 3 lOOmVpp IVpp 5Vpp n n I k k k k 1 k n k 1 rnn...

Page 60: ...ayed code are as in the Figure 5 17 NOTE The STAND BY ON and LOCAUPRESET pushbut tons cannot be tested with this tool If you find any fault continue with traditional troubleshoo ting techniques and re...

Page 61: ...sts should be done with the standard PROM Installed in the counter Switch on the counter Connect an arbitrary signal to the EXT ARM input J5 at the rear panel Trace the signal from J5 to U58 pin 27 Co...

Page 62: ...ls can be added by using the oscilloscopes ADD TRA CE function with the result of approximately zero Check all signals on U63 to U67 NOTE U3 and U67 are located at the bottom side ofthe PCA see Figure...

Page 63: ...Figure 5 22 Typical voltages Input Amplifier Troubleshooting 5 15...

Page 64: ...a 1000 Hz sine wave signal with an amplitude of 1 Vp p to Input A Set the input amplitude to 1 Vp p Measure the AC levels according to Figure 5 22 and Table 5 7 Use the oscilloscope and a 10 MQ probe...

Page 65: ...ude at BUI Check that the amplitude at 1C1 pin 5 is 300 mVp p Check that the amplitude at TS1 collector and TS2 emit ter is 500 mVp p Level Detector Control Disconnect the signal generator from the co...

Page 66: ...oscope to 2 V div and 10 ms div Run the Analog out 1 test Test 10 The ji controlier generates a pulse width modulated signal with a variable duty cycle This PWW signal is converted by U34 to a sawtoot...

Page 67: ...If you find any fault continue with traditional troubleshoo ting techniques and replace defective circuits See also Chapter 4 Circuit Descriptions GPIB Interface Troubleshooting 5 19...

Page 68: ...in the primary circuits are important to the sa fety of the instrument and may only be replaced by compo nents obtained from your local Fluke organization Check the Protective Ground Connection Visua...

Page 69: ...Chapter 6 Calibration Adjustments...

Page 70: ...dangerous to life are always exposed inside the unit when it is connec ted to the iine power Use extreme caution when handiing testing or adjusting the counter Before beginning the calibration adjustm...

Page 71: ...00 fis div Setting A 1 V div 50 n DC Table 6 2 10 MHz Multiplier setup Connect the LF synthesizer to the REFERENCE iNput at the rear of the PM 6681 via a 50 O attenuator Connect the Sampling Oscillosc...

Page 72: ...counter reads 10 MHz 1 Hz See Figure 6 5 Optional Oven Oscillators PM 9690 and PM 9691 Setup Connect the counter to the line power Switch on the counter Press PRESET then press ENTER I Oscilloscope T...

Page 73: ...he calibra tion Now you shall enter the different GPIB addresses for the instruments involved Type the serial number of the counter under test and press ENTER Now you will be asked if you want to cali...

Page 74: ...ct the probe to test point X4 Adjust R168 L1N B and C38 1X B until the signal is ab solutely flat Setup PM 6681 Function VOLTA MAX MIN Input A B 50 n DC Manual trigger level Measuring time 80 ns Atten...

Page 75: ...st C9 10X B until the tilt of the top line is 0 3 V See Figure 6 7 Remove the probe Read the counters display Adjust C38 10X B until the displayed value has increa sed 10 to 30 mV Shift between IX and...

Page 76: ...LF synthesizer Amplitude 1 Vpp Frequency 1000 01 Hz square wave Table 6 9 GPIB interface setup The output amplitude mentioned is the set ampiitude it is oniy vaiid for an open output of the synthesiz...

Page 77: ...O slowly clockwise until the GATE indicator starts blinking The input frequency 900 25 MHz will now be displayed Figure 6 10 Test points and trimmers for the 2 7 GHz HF input NOTE Before beginning any...

Page 78: ...FLUKE service center To verify the 4 2 GHz HF input a sweep frequency synthesi zer Wiltron 6717B 20 is needed it is not possible to make any adjustments to the PM 9625 Therefore if you suspect any fa...

Page 79: ...Chapter 7 Replacement Parts...

Page 80: ...nufactured or selected by Philips to meet specific performance requirements Components that are important for the safety of the instrument Both type of components may be replaced only by com ponents o...

Page 81: ...T 3X08 STFZB TX 4822 502 11691 P 39 Shield PM6681 5322 459 11185 P 168 Screw MRT TT 4X16 STFZB TX 5322 502 13552 P 40 Shield cover PM6681 5322 447 92204 P 172 Screw MFT 4X10 ST FZBTX 5322 502 13641 P...

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Page 83: ...2 B3 Crystalfilter 100 MHz MF UB 5322 242 81692 B4 Crystalfilter 100 MHz MF UB 5322 242 81692 B5 CrystaMOMHz HC 49U 5322 242 81694 C1 Capacitor 2 pF 0 5 2 pF 300V 5322 124 80335 C2 Capacitor 100 nF 10...

Page 84: ...acitor 1 nF 5 63V NPO 1206 4822 122 31746 C41 Capacitor 10 nF 10 63V X7R 1206 4822 122 32442 C118 Capacitor 100 nF 10 63V X7R 1206 4822 122 33496 C42 Capacitor 100 nF 10 63V X7R 1206 4822 122 33496 C1...

Page 85: ...33 pF 5 63V NPO 1206 4822 126 10324 C192 Capacitor 100 nF 10 63V X7R 1206 4822 122 33496 C362 Capacitor 15 pF 5 63V NPO 1206 4822 122 32504 C193 Capacitor 100 nF 10 63V X7R 1206 4822 122 33496 C363 C...

Page 86: ...Battery holder 20mm BH800 5322 256 60311 C442 Capacitor 12 pF 5 63V NPO 1206 4822 122 32139 G1 Battery 3V BR2032 190mAH 20x3 2 4822 138 10082 P C445 Capacitor 100 nF 10 63V X7R 1206 4822 122 33496 GND...

Page 87: ...100PPM 1206 4822 051 51502 L47 Choke 4S2 3 5X6MM 80 2 at 100 MHz 5322 157 61928 R41 Resistor 1 00 kQ 1 1 8 W 100PPM 1206 4822 051 51002 L48 Choke 4S2 3 5X6MM 80 i at 100 MHz 5322 157 61928 R42 Resist...

Page 88: ...M 1206 4822 051 10561 R100 Resistor 100 Cl 1 1 8 W 100PPM 1206 4822 051 51001 R172 Resistor 2 20 kQ 1 1 8 W 100PPM 1206 4822 051 52202 R101 Resistor 100 Cl 1 1 8 W 100PPM 1206 4822 051 51001 R173 Resi...

Page 89: ...r 6 80 kQ 1 1 8 W 100PPM 1206 4822 051 10682 R235 Resistor 56 2 1 1 8 W 100PPM 1206 4822 051 10569 R300 Resistor 6 80 kQ 1 1 8 W 100PPM 1206 4822 051 10682 R236 Resistor 100 2 1 1 8 W 100PPM 1206 4822...

Page 90: ...10561 R453 Resistor 10 0 kQ 1 1 8 W 100PPM 1206 4822 051 51003 R366 Resistor 1 00 kQ 1 1 8 W 100PPM 1206 4822 051 51002 R454 Resistor 10 0 kQ 1 1 8 W 100PPM 1206 4822 051 51003 R367 Resistor 1 00 kQ...

Page 91: ...R522 Resistor 100 kQ 1 1 8 W 100PPM 1206 4822 051 51004 R594 Resistor 820 Q 1 1 8 W 100PPM 1206 5322 116 82264 R523 Resistor 33 Q 1 1 8 W 100PPM 1206 4822 051 10339 R595 Resistor 100 Q 1 1 8 W 100PPM...

Page 92: ...SMD 5322 209 33104 VI Transistor BF513 03A20V SOT23 4822 130 60686 U34 IC CMOS 74AC32D 4X0R2 SOU SMD 5322 209 33104 V2 Transistor BF513 03A20V SOT23 4822 130 60686 U35 IC CMOS 74AC32D 4X0R2 SOU SMD 5...

Page 93: ...A BC817 25 45V SOT23 4822 130 42804 V58 Transistor 0 50 A BC817 25 45V SOT23 4822 130 42804 Description Part Number A Transistor 0 50 A BC817 25 45V SOT23 4822 130 42804 Transistor 0 50 A BC817 25 45...

Page 94: ...TEM 63 4822 130 30953 CATHODE 66 NODE R Pos Description Part Number D203 LED 3mm Yellow 590nm 4 8MCD 10 mA 4822 130 30953 R D204 LED 3mm Yellow 590nm 4 8MCD 10 mA 4822 130 30953 R DL100 Backlight 5322...

Page 95: ...rt Number L7 Choke 0 1H 10 MLF3216DR10K 5322 157 52986 L8 Choke 0 1H 10 MLF3216DR10K 5322 157 52986 L9 Choke 0 1H 10 MLF3216DR10K 5322 157 52986 R1 Resistor 470 Q 1 1 8W 100PPM 1206 5322 116 80444 R2...

Page 96: ...64 TS1 Transistor BFQ67 SOT23 5322 130 42567 TS2 Transistor BFQ67 SOT23 5322 130 42567 Description Part Number TS3 Transistor BC847B 1A45V SOT23 4822 130 60511 TS4 Transistor BC847B 1A45V SOT23 4822 1...

Page 97: ...4822 124 20977 Spring Washer KBA 3 2 ST FZ DIN137 4822 530 80173 P KT1 Osciiiator 10 MHz TCXO 5322 216 94047 R BU1 Connector 10 pin 22 14 2104 4455 BC 5322 267 50336 R1 Resistor 147 1 1 2 WMRS25 4822...

Page 98: ...This page is intentionaiiy ieft blank 7 20 Replacement Parts PM 9678B...

Page 99: ...Chapter 8 Schematic Diagrams...

Page 100: ...mbols conform to lEC standards These symbols are designed to be logical and easy to read The component number is written above the symbol Inside the symbol at the top is an abbreviated description of...

Page 101: ...Drawings Diagrams 8 3...

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Page 104: ...8 6 Drawings Diagrams Basic board Component layout...

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Page 106: ...8 8 Drawings Diagrams Basic board Component layout...

Page 107: ......

Page 108: ...8 10 Drawings Diagrams Basic board Component layout...

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Page 110: ..._ Wm Sfeig mi Jd fR52TiSW j QST of i L _l p j fR354l rRlfi R 551 4 R34i1_ v4B I RajO jB6i iSifR3p im IpMi ra ijR3 6S jri8 Sl Sirgjjg tB3 t viTT 1 MJ Wi w I Iw V I b rw8iO lLi M3 R3S0 R349 iVSo I 0 C44...

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Page 112: ...8 14 Drawings Diagrams Basic board Component layout...

Page 113: ...Drawings Diagrams 8 15...

Page 114: ...8 16 Drawings Diagrams Display Keyboard board Component layout...

Page 115: ...BBBBBBE...

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Page 118: ...8 20 Drawings Diagrams TCXO PM9678B...

Page 119: ...Chapter 9 Appendix...

Page 120: ...at this stage Figure 9 1 Heat the leads and push a thin aluminum sheet between the leads and the pea Figure 9 3 Place solder on the pad Figure 9 7 Use a strong magnifying glas to make sure there are n...

Page 121: ...grounded wrist strap Never touch the component ieads Never touch open connectors Use ESD safe packing materiais Use the packing materiai only once Keep paper and nonconductive plastics etc away from y...

Page 122: ...4822 4822 4822 4822 4822 4822 4822 4822 4822 122 4822 122 4822 122 53030 53050 10758 21644 80082 80173 00120 13144 20001 11185 92204 11658 10004 58390 10545 48830 10222 00002 00003 05037 10097 73307...

Page 123: ...122 32442 S 4822 122 31746 S 4822 122 32442 S 4822 124 40723 S 5322 124 10455 S 4822 122 33496 S 5322 124 10455 S 4822 124 40723 S 5322 124 11418 S 5322 124 11418 S 4822 122 32442 S 5322 124 10685 S...

Page 124: ...34337 S 5322 130 34337 S 5322 130 80255 S 4822 130 60815 S 5322 130 80212 S 5322 130 34337 S 5322 130 33764 S 5322 130 80212 S 5322 130 80212 S 5322 130 80255 S 5322 130 33764 S 5322 130 33764 S 5322...

Page 125: ...22 117 10858 S 4822 051 4822 051 4822 051 4822 051 4822 051 4822 051 4822 051 4822 051 4822 051 4822 051 5322 101 4822 051 4822 051 4822 051 4822 051 4822 051 4822 051 4822 051 4822 051 4822 051 4822...

Page 126: ...82 54702 10792 51003 53301 11074 53302 51001 51001 51002 EsiS Description R39 R4 R40 R402 RESI R403 RESI R404 RESI RESISTOR 220 0ohm 1 125W 100PPM 1206 4822 051 52201 RESISTOR 47 0kohm 0 5 0 125W RC 0...

Page 127: ...6 4822 051 51004 S RESISTOR 56 ohm 1 125W 100PPM 1206 4822 051 10569 S RESISTOR 56 ohm 1 125W 100PPM 1206 4822 051 10569 S RESISTOR 56 ohm 1 125W 100PPM 1206 4822 051 10569 S RESISTOR 390 ohm 1 125W 1...

Page 128: ...25 MA BFR92A 20V SOT23 TRANSISTOR BFG97 0 1A 15V S0223 TRANSISTOR BFS17 05A 15V S0T23 TRANSISTOR BFS17 05A 15V SOT23 TRANSISTOR BFS17 05A 15V SOT23 TRANSISTOR BFS17 05A 15V SOT23 TRANSISTOR BFS17 05A...

Page 129: ...Appendix 9 11 Schematic Diagrams...

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Page 132: ...IKgSI I E3 IC364I IL 29 IIP S3 1...

Page 133: ...I s s I sS h H p 2 SSSSSSSS S 8SSi 5 fSS2 i S b b iiK XXX xn 3 xi mt ommz 5S S Sg I j tt Hu i g SSSSpgggggggggg wSSm mw s zS mi RR S lni maa Mkjl o b uit MSj b S a s S fe PZfe 8 1 as a 5s Logic Circui...

Page 134: ...9 16 Appendix...

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Page 136: ...9 18 Appendix...

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Page 139: ...9 24 Appendix...

Page 140: ...the exchange proce dure Calibration and Adjustment NOTE Before adjusting the oscillator the timer counter must have been continuously connected to the ac power line for at least 24 hours Required tes...

Page 141: ...lue is stable over time 30 min TimeView is an excellent tool for viewing frequency stability over time Attach a new calibration seal sticker so that it covers the hole in the front panel 9 26 Appendix...

Page 142: ...age controlled adjustment range This range is divided into five fixed steps set via DIP switches and a trimmer to fine tune the control voltage Normally the range of the trimmer should be sufficient t...

Page 143: ...This page is intentionaliy ieft blank 9 28 Appendix New OCXOs...

Page 144: ...322 126 13638 S 5322 265 41371 S C5 CAPACITOR lOOnF 20 25V X7R 0805 5322 126 13638 S 2022 552 05597 C51 CAPACITOR 33pF 5 50V NPO 0805 2222 861 15339 4822 122 33575 S C52 CAPACITOR 82pF 5 50V NPO 0805...

Page 145: ...051 10121 051 51001 EsiS Description OR 3 30kohm 1 125W 100PPM 1206 4822 051 53302 S OR 47ohm1 0 1W100PPM 0805 5322 117 12505 S OR 5 60kohm 1 125W 100PPM 1206 4822 051 10562 S OR 1 50kohm 1 0 1 25W 1...

Page 146: ...Appendix Schematic Diagrams PM9671B 9 31 Schematic Diagrams PM9671B...

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Page 149: ...9 34 Appendix Schematic Diagrams PM9671B 7 0 13 r...

Page 150: ...Chapter 10 Index...

Page 151: ...n 6 3 Checking 2 5 Description 4 15 Input location 4 19 F Fan Fan control 4 11 Replacing 3 3 Frequency Range test 2 4 Front panel Keyboard 4 4 LCD drivers 4 4 Functional levels 5 4 Fuses 1 2 G Gate Op...

Page 152: ...9611 Recalibration intervals SeeMTBRC 5 2 Recommended Replacement Parts 7 2 Reference in See External Reference input Reference Oscillator Description 4 14 Reference Oscillators Checking 2 5 Reinstal...

Page 153: ...This page is intentionaiiy left blank 10 4 Index...

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