Motorola GP Series Detailed Service Manual page 111

Table of Contents
Chapter 1 THEORY OF OPERATION
1.0 Introduction ..........................................................................................................1-1
2.0 UHF Transmitter ..................................................................................................1-1
2.1 Power Amplifier ..............................................................................................1-1
2.2 Antenna Switch...............................................................................................1-2
2.3 Harmonic Filter ...............................................................................................1-2
2.4 Antenna Matching Network ............................................................................1-2
2.5 Power Control Integrated Circuit (PCIC) ........................................................1-2
3.0 UHF Transmitter (for ATEX specified models).....................................................1-3
3.1 General...........................................................................................................1-3
4.0 UHF Receiver (All models except those with PCB 8486458Z03 & 8486743Z02)1-5
4.1 Receiver Front-End ........................................................................................1-5
4.2 Receiver Back-End.........................................................................................1-6
4.3 Automatic Gain Control (AGC) .......................................................................1-7
5.0 UHF Reciever (for ATEX specified models).........................................................1-8
5.1 Reciever Front-End ........................................................................................1-8
5.2 Reciever Back-End.........................................................................................1-9
6.0 UHF Receiver (Models with PCB 8486458Z03) ................................................1-10
6.1 Receiver Front-End ......................................................................................1-10
6.2 Receiver Back-End.......................................................................................1-11
7.0 Frequency Generation Circuit ............................................................................1-12
7.1 Synthesizer...................................................................................................1-13
7.2 Voltage Controlled Oscillator (VCO).............................................................1-14
8.0 Controller Information ........................................................................................1-16
8.1 Radio Power Distribution ..............................................................................1-16
8.2 Controller Board ...........................................................................................1-17
9.0 Voice Storage (GP1280 Only) ...........................................................................1-20
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