Hytera MD78X Service Manual page 10

Service Manual
15.1.8 Output Power Control ....................................................................................................... 540
15.1.9 Thermal and Over-voltage Protections ............................................................................ 540
15.1.10 Pressure Pad Switch ...................................................................................................... 540
15.2 Receiver Circuit .......................................................................................................................... 540
15.2.1 Receiver Front-end........................................................................................................... 541
15.2.2 Receiver Back-end ........................................................................................................... 541
15.3 Frequency Generation Unit (FGU) ............................................................................................. 542
15.3.1 PLL Synthesizer ............................................................................................................... 542
15.3.2 Reference Oscillator ......................................................................................................... 542
15.3.3 PLL IC ............................................................................................................................... 542
15.3.4 VCO .................................................................................................................................. 543
15.4 PCB View .................................................................................................................................... 545
15.5 Block Diagram ............................................................................................................................ 549
15.6 Schematic Diagram .................................................................................................................... 552
15.7 Parts List ..................................................................................................................................... 566
15.8 Troubleshooting Flow Chart ....................................................................................................... 607
16. Disassembly and Assembly .......................................................................................................... 613
16.1 Disassembly ............................................................................................................................... 613
16.2 Assembly .................................................................................................................................... 614
17. Exploded View ................................................................................................................................ 616
18. Packing Guide ................................................................................................................................ 620
19. Specifications ................................................................................................................................. 621
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