Motorola HT Series Detailed Service Manual page 6

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Chapter 5 UHF Band 2 Theory of Operation .....................................5-1
5.1 Transmitter.................................................................................................................... 5-1
5.2 Receiver........................................................................................................................ 5-3
5.3 Frequency Generation Circuitry.................................................................................... 5-4
5.4 Synthesizer ................................................................................................................... 5-5
5.5 Voltage-Controlled Oscillator (VCO)............................................................................. 5-6
Chapter 6 VHF Theory of Operation...................................................6-1
6.1 Transmitter.................................................................................................................... 6-1
6.2 Receiver (for all models except those with PCB 8486473Z04) .................................... 6-3
6.3 Receiver (for models with PCB 8486473Z04) .............................................................. 6-5
6.4 Frequency Generation Circuitry.................................................................................... 6-8
6.5 Synthesizer ................................................................................................................... 6-9
6.6 Voltage-Controlled Oscillator (VCO)........................................................................... 6-10
Chapter 7 Low Band, 800 MHz, PassPort & 900 MHz Theory of
Operation ............................................................................7-1
7.1 Introduction ................................................................................................................... 7-1
7.2 Low Band Transmitter................................................................................................... 7-1
7.3 Low Band Receiver....................................................................................................... 7-3
7.4 Synthesizer ................................................................................................................... 7-5
7.5 Voltage Control Oscillators (VCO) ................................................................................ 7-6
7.6 800 MHz Transmitter .................................................................................................... 7-7
7.7 800 MHz Receiver ........................................................................................................ 7-9
7.8 Synthesizer ................................................................................................................. 7-12
7.9 Trunked Radio Systems ............................................................................................. 7-15
7.10 900 MHz Transmitter .................................................................................................. 7-17
7.11 900 MHz Receiver ...................................................................................................... 7-19
7.12 Frequency Generation Circuitry.................................................................................. 7-24
7.13 900 MHz Synthesizer.................................................................................................. 7-24
7.14 900 MHz Voltage Control Oscillator (VCO) ................................................................ 7-26
Chapter 8 Maintenance .......................................................................8-1
8.1 Introduction ................................................................................................................... 8-1
8.2 Preventive Maintenance ............................................................................................... 8-1
8.3 Inspection ..................................................................................................................... 8-1
8.4 Safe Handling of CMOS and LDMOS........................................................................... 8-2
8.5 General Repair Procedures and Techniques ............................................................... 8-2
8.6 Recommended Test Tools............................................................................................ 8-4
8.7 Replacing the Circuit Board Fuse ................................................................................. 8-5
8.8 Removing and Reinstalling the Circuit Board ............................................................... 8-6
8.9 Power Up Self-Test Error Codes .................................................................................. 8-7
8.10 UHF Band 1 Troubleshooting Charts............................................................................ 8-8
8.11 UHF Band 2 Troubleshooting Charts.......................................................................... 8-17
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