Motorola CM200 Service Manual page 154

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9.0 Receive Audio Circuits....................................................................................... 2-19
9.1 Squelch Detect .......................................................................................... 2-19
9.2 Audio Processing and Digital Volume Control ........................................... 2-20
9.3 Audio Amplification Speaker (+) Speaker (-) ............................................. 2-20
9.4 Handset Audio ........................................................................................... 2-21
9.5 Filtered Audio and Flat Audio .................................................................... 2-21
10.0 Receive Signalling Circuits ................................................................................ 2-21
10.1 Sub-Audio Data (PL/DPL) and High Speed Data Decoder........................ 2-21
10.2 Alert Tone Circuits ..................................................................................... 2-22
Chapter 3 TROUBLESHOOTING CHARTS
1.0 Troubleshooting Flow Chart for Receiver RF (Sheet 1 of 2)................................ 3-2
1.1 Troubleshooting Flow Chart for Receiver (Sheet 2 of 2) ............................. 3-3
2.0 Troubleshooting Flow Chart for 40 W Transmitter (Sheet 1 of 3) ........................ 3-4
2.1 Troubleshooting Flow Chart for 40 W Transmitter (Sheet 2 of 3) ................ 3-5
2.2 Troubleshooting Flow Chart for 40 W Transmitter (Sheet 3 of 3) ................ 3-6
3.0 Troubleshooting Flow Chart for Synthesizer........................................................ 3-7
4.0 Troubleshooting Flow Chart for VCO................................................................... 3-8
5.0 Troubleshooting Flow Chart for DC Supply (1 of 2) ............................................. 3-9
5.1 Troubleshooting Flow Chart for DC Supply (2 of 2)................................... 3-10
Chapter 4 UHF2 PCB/ SCHEMATICS/ PARTS LISTS
1.0 Allocation of Schematics and Circuit Boards ....................................................... 4-1
1.1 UHF2 and Controller Circuits....................................................................... 4-1
2.0 UHF 25-40 W Band 2 PCB 8486577Z01 / Schematics ....................................... 4-3
UHF 2 Interconnection between Main Board and Power Amplifier
Compartment ...................................................................................................... 4-3
UHF2 (438-470 MHz) 25-40 W 8486577Z01, Top Side .................................... 4-4
UHF2 (438-470 MHz) 25-40 W 8486577Z01, Bottom Side ................................ 4-5
UHF2 (438-470 MHz) 25-40 W Main Circuit (Sht 1 of 2) .................................... 4-6
UHF2 (438-470 MHz) 25-40 W Main Circuit (Sht 2 of 2) .................................... 4-7
UHF2 (438-470 MHz) 25-40 W Transmitter (Sht 1 of 2) ..................................... 4-8
UHF2 (438-470 MHz) 25-40 W Transmitter (Sht 2 of 2) ..................................... 4-9
UHF2 (438-470 MHz) 25-40 W Synthesiser and VCO (Sht 1 of 2) .................. 4-10
UHF2 (438-470 MHz) 25-40 W Synthesiser and VCO (Sht 2 of 2) .................. 4-11
UHF2 (438-470 MHz) 25-40 W Receiver Front and Back End (Sht 1 of 2) ...... 4-12
UHF2 (438-470 MHz) 25-40 W Receiver Front and Back End (Sht 2 of 2) ...... 4-13
UHF2 (438-470 MHz) 25-40 W DC and Audio Circuits (Sht 1 of 2) .................. 4-14
UHF2 (438-470 MHz) 25-40 W DC and Audio Circuits (Sht 2 of 2) .................. 4-15
UHF2 (438-470 MHz) 25-40 W Microprocessor and Controller
Circuits (Sht 1 of 2) ........................................................................................... 4-16
UHF2 (438-470 MHz) 25-40 W Microprocessor and Controller
Circuits (Sht 2 of 2) ........................................................................................... 4-17
UHF2 (438-470 MHz) 25-40 W Power Control Circuit ...................................... 4-18
2.1 UHF2 PCB 8486577Z01 Parts List 25-40 W ............................................. 4-19