Motorola EP450 Service Manual

Table of Contents iii
HKLN4216A November 24, 2003
Table of Contents
Foreword............................................................................................................................................ii
Product Safety and RF Exposure Compliance ..................................................................................ii
Computer Software Copyrights..........................................................................................................ii
Document Copyrights ........................................................................................................................ii
Disclaimer ..........................................................................................................................................ii
List of Figures .............................................................................................viii
List of Tables .................................................................................................ix
Related Publications......................................................................................x
Module 1: VHF 146-174 MHz
Chapter 1 Test Equipment, Service Aids, and
Service Tools....................................................................... 1-1
1.1 Test Equipment.............................................................................................................................. 1-1
1.2 Service Aids................................................................................................................................... 1-2
Chapter 2 DC Power Distribution ........................................................ 2-1
2.1 DC Regulation and Distribution ..................................................................................................... 2-1
Chapter 3 Controller Theory of Operation.......................................... 3-1
3.1 Controller ....................................................................................................................................... 3-1
3.1.1 Microprocessor Circuitry ...................................................................................................3-1
3.1.1.1 Memory Usage ........................................................................................................ 3-2
3.1.1.2 Control and Indicator Interface ................................................................................ 3-2
3.1.1.3 Serial Bus Control of Circuit Blocks ......................................................................... 3-2
3.1.1.4 Interface to RSS Programming................................................................................ 3-3
3.1.1.5 Storage of Customer-Specific Information............................................................... 3-3
3.1.1.6 Sensing of Externally-Connected Accessories ........................................................ 3-3
3.1.1.7 Microprocessor Power-Up, Power-Down and Reset Routine.................................. 3-3
3.1.1.8 Boot Mode Control................................................................................................... 3-4
3.1.1.9 Microprocessor 7.3975 MHz Clock.......................................................................... 3-4
3.1.1.10 Battery Gauge.......................................................................................................... 3-4
3.1.2 Audio Circuitry .................................................................................................................. 3-4
3.1.2.1 Transmit and Receive Low-Level Audio Circuitry .................................................... 3-4
3.1.2.2 Audio Power Amplifier ............................................................................................. 3-5
3.1.2.3 Internal Microphone Audio Voice Path .................................................................... 3-5
3.1.2.4 PTT Circuits .............................................................................................................3-6
3.1.2.5 VOX Operation ........................................................................................................ 3-6
3.1.2.6 Programming and Flashing Through Microphone Jack ........................................... 3-6

Motorola EP450 Specifications

General

Channel Capacity	16 channels
Operating Temperature	-30°C to +60°C
IP Rating	IP54
Frequency Range	VHF: 136-174 MHz, UHF: 403-470 MHz
Weight	Approximately 350g (with standard battery)