User Manual
Table Of Contents
- 1GENERAL
- 1.1Introduction
- 1.2Manual Organization
- 1.3VT-4B 136 - 174 MHz Transmitter Family Models
- 1.4Performance Specifications
- 1.4.1General
- 1.4.2Audio Specifications
- 1.4.3Physical Specifications
- 2THEORY OF OPERATION
- 2.1Transmitter Operation
- 2.2Transmitter Programming
- 2.2.1Transmitter Wide Options
- 2.2.1.1Disable Front Panel Led
- 2.2.1.2Secure Hardware Equipped
- 2.2.1.3Allow Emergency Transmissions
- 2.2.1.4Allow Radio Inhibit
- 2.2.1.5Allow Radio Check
- 2.2.1.6Enable Status
- 2.2.1.7Frequency Band
- 2.2.2Channel Wide Settings
- 2.2.2.1Frequency
- 2.2.2.2Voice/Signal Type
- 2.2.2.3Squelch Type
- 2.2.2.4CTCSS Tone
- 2.2.2.5Enable Reverse Burst
- 2.2.2.6DCS Code
- 2.2.2.7DCS Invert
- 2.2.2.8Enable Turn Off Code
- 2.2.2.9Transmitter Power
- 2.2.2.10Channel Bandwidth
- 2.2.2.11Deviation
- 2.2.2.12Time Out Timer
- 2.2.2.13Channel Status
- 2.2.2.14Transmitter Pre-emphasis
- 2.2.2.15NAC Transmitter Code
- 2.2.2.16NAC Transmitter
- 2.3Transmitter Programming using Motorola Radio Service Software
- 2.4Secure Communications
- 2.5Transmitter Assembly and Adjustment
- 2.5.1Controller Board Alignment
- 2.5.1.1Reference Oscillator Adjustment
- 2.5.1.2Transmitter Deviation Balance Adjustment
- 2.5.1.3Transmitter Deviation Limit Adjustment
- 2.5.2Amplifier Alignment
- 2.5.3Frequency Change
- 2.6Recommended Test Equipment List
- 2.7Repair Note
- 2.8Printed Circuitboard Numbering Convention
- 3ILLUSTRATIONS
- 3.1MT-4 Base Transmitter Front Panel
- 3.2MT-4 Transmitter Case - Exploded View
- 3.3Digital Base Transmitter Block Diagram
- 3.4Digital Base Transmitter Schematic Diagram
- 3.5Digital Base Transmitter Main Board Component Layout (Bottom)
- 3.6Digital Base Transmitter Main Board Component Layout (Top)
- 4PARTS LIST
- 4.1P25 Base Transmitter Main Board Parts List
- 4.1.1P25 Base Transmitter Main Board Electrical Parts List
- 4.1.2P25 Base Transmitter Mechanical Parts List
- 5REVISION HISTORY
DE
DANIELS
ELECTRONICS
4-4 VT-4B150 VHF Project 25
Digital
Base
Transmitter
Instruction
Manual
SCREW,
M2.5
x 12 FLAT/PHIL, A2
5812-2M5FP12S
9
SCREW,
M3 X 6, OVAL
C/S/PHIL,
Ni 5812-3M0VP06N 2
SCREW,
M3 X 6 PAN/PHIL, A2
5812-3M0PP06S
4
SCREW,
M3 x 8,OVAL
C/S/PHIL,A2
5812-3M0VP08S 4
SCREW,
M5 X 8 FLAT/PHIL, A2
5812-5M0FP08S
4
SHIELD,
RF
BOARD,
SEC
DIG TX TBA 1
SHIELD, CONTROLLER BOARD,
SEC
DIG TX TBA 1
SCREW,
M2.5
x 3 FLAT/PHIL, A2 TBA 4
SECURE
DIGITAL
TX FRONT PANEL TBA 1
SLOTTED
STANDOFF,
5mmOD,
6.5mm
L,M2.5 TBA 6
STANDOFF,
5mmOD, 6mm L,M2.5 TBA 4
WIRE,
TFE/STRAND.,
24AWG, RED 7121-24S19362 8 CM
WIRE,
TFE/STRAND.,
24AWG,BLACK
7121-24S19360 8 CM