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Table of Contents
Chapter 1
MODEL CHART AND TECHNICAL SPECIFICATIONS
1.0 GP320/GP340/GP360/GP380 Model Chart.........................................................1-1
2.0 GP140 Model Chart .............................................................................................1-2
3.0 GP640/GP680 Model Chart .................................................................................1-2
4.0 GP1280 Model Chart ...........................................................................................1-3
5.0 GP240/GP280/GP540/GP580 Model Chart.........................................................1-4
6.0 Technical Specifications ......................................................................................1-5
Chapter 2
THEORY OF OPERATION
1.0 Introduction ..........................................................................................................2-1
2.0 VHF Transmitter...................................................................................................2-1
2.1 Power Amplifier ..............................................................................................2-1
2.2 Antenna Switch...............................................................................................2-2
2.3 Harmonic Filter ...............................................................................................2-2
2.4 Antenna Matching Network ............................................................................2-2
2.5 Power Control Integrated Circuit (PCIC) ........................................................2-2
3.0 VHF Receiver (for all models except those with PCB8486473Z04) ....................2-3
3.1 Receiver Front-End ........................................................................................2-3
3.2 Receiver Back-End.........................................................................................2-4
3.3 Automatic Gain Control (AGC) .......................................................................2-5
4.0 VHF Receiver (for models with PCB 8486473Z04) .............................................2-6
4.1 Receiver Front-End ........................................................................................2-6
4.2 Receiver Back-End.........................................................................................2-7
4.3 Automatic Gain Control (AGC) .......................................................................2-8
5.0 Frequency Generation Circuit ..............................................................................2-8
5.1 Synthesizer.....................................................................................................2-9
5.2 Voltage Controlled Oscillator (VCO).............................................................2-10
6.0 Voice Storage (GP1280)....................................................................................2-12
Chapter 3
TROUBLESHOOTING CHARTS
1.0 Troubleshooting Flow Chart for Receiver for all models except those with PCB
8486473Z04.........................................................................................................3-1
2.0 Troubleshooting Flow Chart for Receiver for models with PCB 8486473Z04......3-3
3.0 Troubleshooting Flow Chart for Transmitter ........................................................3-5
4.0 Troubleshooting Flow Chart for Synthesizer........................................................3-6
5.0 Troubleshooting Flow Chart for VCO...................................................................3-7
6.0 Troubleshooting Flow Chart for Receive Message/Personal Memo Recording...3-8
7.0 Troubleshooting Flow Chart for Message Playback.............................................3-9
Summary of Contents for GP1280 Series
Page 1: ...Professional Radio GP Series VHF 136 174MHz Service Information Issue November 2004 ...
Page 24: ...2 14 THEORY OF OPERATION ...
Page 34: ...3 10 TROUBLESHOOTING CHARTS ...
Page 38: ...4 4 VHF PCB SCHEMATICS PARTS LISTS ...
Page 50: ...4 16 VHF PCB 8486062B12 Parts List Intentionally Left Blank ...
Page 54: ...4 20 VHF PCB 8486101B09 Schematics GP1280 Intentionally Left Blank ...
Page 64: ...4 30 VHF PCB 8486062B14 Parts List Intentionally Left Blank ...
Page 108: ...4 74 VHF PCB 8486473Z04 Radio Parts List Intentionally Left Blank ...