User's Guide

DE
DANIELS
ELECTRONICS
Transmitter Main Board Instruction Manual iii
TABLE OF CONTENTS
Page
1 GENERAL .................................................................................................................. 1-1
1.1 Introduction.................................................................................................... 1-1
1.2 Performance Specifications............................................................................ 1-1
1.2.1 General............................................................................................... 1-1
1.2.2 Audio Specifications .......................................................................... 1-2
2 THEORY OF OPERATION....................................................................................... 2-1
2.1 Transmitter Main Board................................................................................. 2-1
2.1.1 General............................................................................................... 2-1
2.1.2 Transmitter Push-To-Talk.................................................................. 2-1
2.1.2.1 Microphone PTT.................................................................... 2-1
2.1.2.2 PTT With Time-Out-Timer.................................................... 2-2
2.1.2.3 PTT No Time-Out-Timer....................................................... 2-2
2.1.2.4 Optional Relay ....................................................................... 2-2
2.1.2.5 PTT Output............................................................................ 2-3
2.1.2.6 PTT Voltage Switching .......................................................... 2-3
2.1.2.7 Transmitter Standby Modes................................................... 2-3
2.1.3 Audio Circuits.................................................................................... 2-4
2.1.3.1 Microphone Audio................................................................. 2-5
2.1.3.2 Received Audio ...................................................................... 2-5
2.1.4 Channel Selection............................................................................... 2-5
2.1.4.1 Synthesized Transmitter......................................................... 2-5
2.1.4.2 Crystal Controlled Transmitter............................................... 2-6
2.1.5 Amplifier Circuits............................................................................... 2-6
2.1.6 Time-Out-Timer Circuitry.................................................................. 2-6
2.2 MT-3 Front Panel Board................................................................................ 2-8
2.3 MT-3 Audio Processor (Version 1.6) ............................................................ 2-8
2.3.1 General............................................................................................... 2-8
2.3.2 Power Requirements .......................................................................... 2-8
2.3.3 Audio Processor Turn-on Time.......................................................... 2-9
2.3.4 Audio Processor Signals.................................................................... 2-9
2.3.4.1 Audio Processor Outputs....................................................... 2-9
2.3.4.2 Audio Processor Modulation Output ..................................... 2-10
2.3.4.3 Audio Processor Low Frequency / Direct Mod. Output......... 2-10
2.3.4.4 Audio Processor Inputs.......................................................... 2-10
2.3.4.5 Audio Processor Microphone Input....................................... 2-11
2.3.4.6 Audio Processor Balanced Input............................................ 2-11
2.3.4.7 Audio Processor Auxiliary Input............................................ 2-11
2.3.4.8 Audio Processor Subtone Inputs............................................ 2-11
2.3.4.9 Audio Processor Direct Modulation Input ............................. 2-12
2.4 MT-3 Audio Processor (Version 1.8) ............................................................ 2-12