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
4-2 VT-4B150 VHF Project 25
Digital
Base
Transmitter
Instruction
Manual
Ref
Desig Description Part No.
J11
CONN.,
SMB
JACK,
SM,
STRHT.
TBA
LED1 LED, GREEN, BILEVEL,RA
PC
MNT 2017-091N12GN
LPF1
FILTER,
SM,
LPF1
EM1LPF,
360pF,FER
1306-T361F2D5
LPF2
FILTER,
SM,
LPF2
EM1LPF,
360pF,FER
1306-T361F2D5
LPF3
FILTER,
SM,
LPF3
EM1LPF,
360pF,FER
1306-T361F2D5
LPF4
FILTER,
SM,
LPF4
EM1LPF,
360pF,FER
1306-T361F2D5
LPF5
FILTER,
SM,
LPF5
EM1LPF,
360pF,FER
1306-T361F2D5
LPF6
FILTER,
SM,
LPF8
EM1LPF,
360pF,FER
1306-T361F2D5
LPF7
FILTER,
SM,
LPF9
EM1LPF,
360pF,FER
1306-T361F2D5
LPF8
FILTER,
SM,
LPF8
EM1LPF,
360pF,FER
1306-T361F2D5
LPF9
FILTER,
SM,
LPF6
EM1LPF,
360pF,FER
1306-T361F2D5
LPF10
FILTER,
SM,
LPF9
EM1LPF,
360pF,FER
1306-T361F2D5
LPF11
FILTER,
SM,
LPF9
EM1LPF,
360pF,FER
1306-T361F2D5
LPF12
FILTER,
SM,
LPF9
EM1LPF,
360pF,FER
1306-T361F2D5
LPF13
FILTER,
SM,
LPF9
EM1LPF,
360pF,FER
1306-T361F2D5
LPF14
FILTER,
SM,
LPF10
EM1LPF,
360pF,FER
1306-T361F2D5
LPF15
FILTER,
SM,
LPF9
EM1LPF,
360pF,FER
1306-T361F2D5
LPF16
FILTER,
SM,
LPF9
EM1LPF,
360pF,FER
1306-T361F2D5
LPF17
FILTER,
SM,
LPF6
EM1LPF,
360pF,FER
1306-T361F2D5
LPF18
FILTER,
SM,
LPF6
EM1LPF,
360pF
,FER
1306-T361F2D5
LPF19
FILTER,
SM,
LPF6
EM1LPF,
360pF,FER
1306-T361F2D5
LPF20
FILTER,
SM,
LPF6
EM1LPF,
360pF,FER
1306-T361F2D5
LPF21
FILTER,
SM,
LPF6
EM1LPF,
360pF,FER
1306-T361F2D5
LPF22
FILTER,
SM,
LPF6
EM1LPF,
360pF,FER
1306-T361F2D5
LPF23 FILTER,
SM,
LPF6
EM1LPF,
360pF,FER
1306-T361F2D5
LPF24
FILTER,
SM,
LPF6
EM1LPF,
360pF,FER
1306-T361F2D5
LPF25
FILTER,
SM,
LPF6
EM1LPF,
360pF,FER
1306-T361F2D5
LPF26
FILTER,
SM,
LPF9
EM1LPF,
360pF,FER
1306-T361F2D5
LPF27
FILTER,
SM,
LPF9
EM1LPF,
360pF,FER
1306-T361F2D5
P1 CONNECTOR, F48 MALE, RA PCB 3720-6048M0RA
Q1
MOSFET,
2N7002LT1 N-CHAN,SOT23 2142-2N7002L0
Q2
MOSFET,
2N7002LT1 N-CHAN,SOT23 2142-2N7002L0
Q3
MOSFET,
2N7002LT1 N-CHAN,SOT23 2142-2N7002L0
R1
RES.,
SM,
82K5 0805, 1%,100ppm 1150-4A8252FP
R2
RES.,
SM,
15K0 0805, 1%,100ppm 1150-4A1502FP
R3
RES.,
SM,
10K0 0805, 1%,100ppm 1150-4A1002FP
R4
RES.,
SM,
0R0 ZERO OHM
JUMPER,1206
1150-0B0R0000
R5
RES.,
SM,
604R0 1206, 1%,100ppm 1150-2B6040FP
R6
POT.,
SM,
5K0 12T, TOP ADJUST 1172-M20502W5
R7 RE
S.,
SM,
10K0 0805, 1%,100ppm 1150-4A1002FP
R8
RES.,
SM,
47K5 0805, 1%,100ppm 1150-4A4752FP
R9
POT.,
SM,
5K0 12T, TOP ADJUST 1172-M20502W5
R10
RES.,
SM,
1K0 0805, 1%,100ppm 1150-3A1001FP
R11
RES.,
SM,
47K5 0805, 1%,100ppm 1150-4A4752FP
R12
RES.,
SM,
47K5 0805, 1%,100ppm 1150-4A4752FP
R13
RES.,
SM,
604R0 0805, 1%,100ppm 1150-2A6040FP
R14
RES.,
SM,
68K1 1206, 1%,100ppm 1150-4B6812FP
R15
RES.,
SM,
1K0 1206, 1%,100ppm 1150-3B1001FP
R16
RES.,
SM,
1K0 1206, 1%,100ppm 1150-3B1001FP