Table Of Contents - Realistic HTX-404 Service Manual

Table of Contents

Contents1
Specifications2
Disassembly4
Block Diagram6
Theory Of Operation7
Transmitter7
Microphone Audio Circuit7
Automatic Power Control7
Rx Vco8
Tx Vco8
Loop Filter8
Pll Frequency Synthesizer8
Programmable Dividers9
Phase Detector9
Receiver9
Rf Amplifier9
Microprocessor Controller10
Receiver Audio Circuit10
High-Pass Filter Module10
Audio Amplifier Module10
Power Switching Circuit11
Ctcss Receive11
Ctcss Transmit11
Dtmf Decoding Circuit11
Control And Indicator Circuit12
External Ptt Control Circuit12
Channel Select Circuit12
Squelch Level Indicator12
Alignment13
Alignment Test Point And Parts Lcoations13
Phase Locked Loop And Cpu Section14
Transmitter Section15
Receiver Section17
Troubleshooting Hints18
Error Display19
Internal Ram Error19
Pll Unlock Error19
Wiring Diagram20
Printed Circuit Boards21
Rf Pcb: Top View21
Rf Pcbl Bottom View22
Chip Component Side View23
Keypad Side View24
High Press Filter Pcb26
Top View26
Bottom View26
Mic Pcb26
Auto Power Control Pcb27
Ptt Pcb27
Top Pcb28
Audio Pcb29
Vco Pcb30
Flexible Pcb31
Exploded View32
Exploded View Parts List33
Electrical Parts List37
Semiconductor Voltage Chart50
Tone Squelch Function51
Dtmf Squelch Function52
Diode52
Ic/Ptt Pcb52
Back Light Function53
Sub Board Pcb53
Semiconductor Lead Identification54
Ic Internal Connection58
Schematic Diagrams65
End Of Document66