Motorola Vhf 136 174 Mhz Uhf 435 480 Mhz 6881096c38 Manual
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6881096C38March, 2006 VHF (136-174 MHz) Band Information: Block Diagrams 7-11 7.4.4 Transmitter Figure 7-5. 7.4.5 Receiver Figure 7-6. ANTTo Receiver TX +B +B TX 5V DAC TX Hamonics Filter C440-445,L415,416 Matching Network C446-448,451,452 L418,419 Power Control Q419 ANT Switch Q409,410 Buffer AMP Q414Coupler R445Pre Driver Q413P in VCOFinal AMP Q411PA Q412 DAC RX DAC RX From VCOFrom ANT Switch 2-Pole Band Pass Filter Q4012-Pole Band Pass Filter Q4052-Pole Crystal Filter F402 2nd Local 44.654MHz...
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March, 20066881096C38 7-12VHF (136-174 MHz) Band Information: Troubleshooting Charts 7.5 Troubleshooting Charts Figure 7-7. Troubleshooting Flow Chart for Receiver Sta rt Very low or no 12 dB SINAD Noise at spkr when radio is unsqu’d? Is 1st LO at C431 >2 dBm? Inject on channel signal at RF port, C429 Inject a 45.1 MHz signal at R467 SINAD 1Check IFIC Q506 (see below) Noise at pin 9 of IFIC Q506? Check VCO/Synth Inject on channel signal at C402 Check harmonic filter and antenna path Check...
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6881096C38March, 2006 VHF (136-174 MHz) Band Information: Troubleshooting Charts 7-13 Figure 7-8. Troubleshooting Flow Chart for Transmitter Sta rt No Power Is +5VTX and TXB+ OK? Is current OK? Is DAC TX High or Low? Is Pin OK? Check Q201, Q202, Q206 & Q209 Check Voltages in Power Control Circuit Check Voltages in PA L i n e - u pTroubleshoot VCO Done Power OK? 1. Check Pin Diodes 2. Check Harmonic Fil- Inspect/Repair TX Output Network NO NO LOW HIGH YES NO NO YESYESYES Check Pin to Q419 Pin 1 Is
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March, 20066881096C38 7-14VHF (136-174 MHz) Band Information: Troubleshooting Charts Figure 7-9. Is information from mP Q101 correct? Is Q330 correc- tor AT4.65 VDC? Is Q314 Emitter AT=13VDC Is Q310 Pin 2 4.3 VDC in TX? Troubleshooting Flow Chart for Synthesizer Sta rt Visual check of the Board OK?Correct Problem Check 5V Regulator +5VQ323 at Pins 3, 4Is 14.4MHz Signal at Q323 Pin 1?Check X301,C337,C3 38,C336 Are signals at Pins 8 of Q323 ? Check Q301, L303,C303,R301, C304 & R302 Fix...
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6881096C38March, 2006 VHF (136-174 MHz) Band Information: Troubleshooting Charts 7-15 Figure 7-10. Troubleshooting Flow Chart for Microcontroller START APPLY POWER TO RADIO AND WAS GOOD OR BAD POWER-ON YES DONE WAS GOOD POWER-ON BEEP ARE ALERT TONES ENABLED IN SPM USE SPM TO ENABLE TONES INVOKE FACTORY RESET IN SPM WAS GOOD POWER ON BEEP PRESENT MAIN RADIO BOARDS MUST BE REPLACED ARE TONES PRESENT ON POWER UP AT CN101 PIN 3? AUDIO PROBLEM, TROUBLE- SHOOT AUDIO CKT WITH POWER CONNECTED TO RADIO AND THE...
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March, 20066881096C38 7-16VHF (136-174 MHz) Band Information: Troubleshooting Charts Figure 7-11. Make sure Synthesizer is working correctly. 1.6 VDC at Q308 Base? 4.65 VDC at Q414 collector? =151 mVrms at Terminal of C311? Supply DC at Q329? 0.9 VDC at Q308 emitter? Are Q325Pin’s emitter at 2.1VDC, collector at 3.8VDC, base at 2.9VDC? Q324 emitter at 1.0VDC, collector at 4.0VDC, base at 1.7VDC ? 0.9 VDC at Q308 emitter ? 1.6 VDC at Q308 base ? 4.65 VDC at Q416 collector? Troubleshooting Flow...
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VHF 136-174 MHz Circuit Board/Schematic Diagrams and Parts List7-176881096C38March, 20067.6 VHF 136-174 MHz Circuit Board/Schematic Diagrams and Parts List Figure 7-12. VHF 136-174 MHz Controller Board (K305E501-01) Top Side Bottom Side Chapter 7
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7-18 VHF 136-174 MHz Circuit Board/Schematic Diagrams and Parts ListMarch, 20066881096C38Figure 7-13. VHF 136-174 MHz Complete Controller Board Schematic Diagram (K305E501-01) R1200 Q1 1 5HL002-Y11 R109330 R108 330 A0 1 A12 A23 Vss4 SDA 5 SCL6 TEST7 Vcc 8 Q114 S-24C16AFJ-01 R127 12.4k R1286.98KC129 0.01 R11051KR11151K R11213K R11322K R11443K R115130K R11618KR117 33KR118 100K C131 33p C132 33p 4 OUT11 OUT22INGND3 AB 4 OUT11IN UP DOWN CD COM01 COM12 COM23 COM34 SEG05 SEG16 SEG27 SEG38 SEG49 SEG510 SEG611...
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VHF 136-174 MHz Circuit Board/Schematic Diagrams and Parts List7-196881096C38March, 2006 Figure 7-14. VHF 136-174 MHz Main Board Top Side (K305E502-01)
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7-20 VHF 136-174 MHz Circuit Board/Schematic Diagrams and Parts ListMarch, 20066881096C38Figure 7-15. VHF 136-174 MHz Main Board Bottom Side (K305E502-01)