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Table of Contents
Chapter 1 THEORY OF OPERATION
1.0 Overview.............................................................................................................. 1-1
2.0 Radio Power Distribution ..................................................................................... 1-1
3.0 Controller Circuits ................................................................................................ 1-3
3.1 General .......................................................................................................... 1-3
3.2 Microprocessor Circuitry ................................................................................ 1-4
3.3 Audio Circuitry................................................................................................ 1-8
3.4 Keypad ......................................................................................................... 1-11
3.5 Speaker and Microphone ............................................................................. 1-11
3.6 LCD Display Module .................................................................................... 1-11
Chapter 2 TROUBLESHOOTING CHARTS
1.0 Troubleshooting Flow Chart for Board and IC Signals
(includes Controller, DC Regulation and Audio).................................................. 2-1
Chapter 3 CONTROLLER SCHEMATICS
1.0 Allocation of PCBs and Schematic Diagrams...................................................... 3-1
2.0 Controller Schematics (includes Keypad and Speaker/Microphone) .................. 3-3
3.0 Keypad Board Parts List (8466565A01-O) .......................................................... 3-9