Parts List
Table Of Contents
- 1GENERAL
- 2SYSTEM OVERVIEW
- 2.1Transmitter Operation
- 2.2Frequency Selection
- 2.2.1Synthesizer Transmitter
- 2.3Transmitter Assembly and Adjustment
- 2.3.1Complete Transmitter Alignment
- 2.3.2Frequency Change
- 2.3.3Output Power Adjustment
- 2.3.4Deviation Setting
- 2.3.5Setting RF Alarm Thresholds
- 2.4Recommended Test Equipment List
- 2.5Repair Note
- 2.6Printed Circuitboard Numbering Convention
- 3ILLUSTRATIONS
- 4PARTS LIST
- 5REVISION HISTORY
- TRANSMITTER MAIN BOARD
- 1GENERAL
- 2THEORY OF OPERATION
- 2.1 Transmitter Main Board
- 2.1.1General
- 2.1.2Transmitter Push-To-Talk
- 2.1.2.1Microphone PTT
- 2.1.2.2PTT With Time-Out-Timer
- 2.1.2.3PTT No Time-Out-Timer
- 2.1.2.4Optional Relay
- 2.1.2.5PTT Output
- 2.1.2.6PTT Voltage Switching
- 2.1.2.7Transmitter Standby Modes
- 2.1.3Audio Circuits
- 2.1.3.1Microphone Audio
- 2.1.3.2Received Audio
- 2.1.4Channel Selection
- 2.1.4.1Synthesized Transmitter
- 2.1.4.2Crystal Controlled Transmitter
- 2.1.5Amplifier Circuits
- 2.1.6Time-Out-Timer Circuitry
- 2.2MT-3 Front Panel Board
- 2.3MT-3 Audio Processor (Version 1.6)
- 2.3.1General
- 2.3.2Power Requirements
- 2.3.3Audio Processor Turn-on Time
- 2.3.4Audio Processor Signals
- 2.3.4.1Audio Processor Outputs
- 2.3.4.2Audio Processor Modulation Output
- 2.3.4.3Audio Processor Low Frequency / Direct Mod. Output
- 2.3.4.4Audio Processor Inputs
- 2.3.4.5Audio Processor Microphone Input
- 2.3.4.6Audio Processor Balanced Input
- 2.3.4.7Audio Processor Auxiliary Input
- 2.3.4.8Audio Processor Subtone Inputs
- 2.3.4.9Audio Processor Direct Modulation Input
- 2.4MT-3 Audio Processor (Version 1.8)
- 2.4.1General
- 2.4.2Power Requirements
- 2.4.3Audio Processor Turn-on Time
- 2.4.4Audio Processor Signals
- 2.4.4.1Audio Processor Outputs
- 2.4.4.2Audio Processor Modulation Output
- 2.4.4.3Audio Processor Low Frequency / Direct Mod. Output
- 2.4.4.4Audio Processor Inputs
- 2.4.4.5Audio Processor Microphone Input
- 2.4.4.6Audio Processor Balanced Input
- 2.4.4.7Audio Processor Auxiliary Input
- 2.4.4.8Audio Processor Subtone Inputs
- 2.4.4.9Audio Processor Direct Modulation Input
- 2.5Low Frequency Modulation
- 3TRANSMITTER ALIGNMENT
- 3.1General
- 3.2Repair Note
- 3.3Printed Circuitboard Numbering Convention
- 3.4Recommended Test Equipment List
- 3.5Standard Factory Settings and Jumper Configuration
- 3.5.1MT-3 Transmitter Board Factory Configuration
- 3.5.2MT-3 Audio Processor Factory Configuration (Version 1.6)
- 3.6MT-3 Transmitter Board Alignment
- 3.6.1General
- 3.6.2MT-3 Transmitter Board Test Points
- 3.7Module Installation and Removal
- 3.8MT-3 Audio Processor Alignment (Version 1.6)
- 3.8.1General
- 3.8.2MT-3 Audio Processor Standard Deviation Adjustment
- 3.9Standard Factory Settings and Jumper Configuration
- 3.9.1MT-3 Audio Processor Factory Configuration (Version 1.8)
- 3.10MT-3 Audio Processor Alignment (Version 1.8)
- 3.10.1General
- 3.10.2MT-3 Audio Processor Standard Deviation Adjustment
- 3.11Low Frequency Modulation Configuration
- 3.11.1MT-3 Transmitters
- 3.11.2MT-3 Transmitter Audio Processors
- 3.11.3Synthesizer and Crystal Controlled Oscillator
- 3.11.4Tuning the Transmitter
- 4TRANSMITTER INTERCONNECT PIN DEFINITIONS
- 5ILLUSTRATIONS AND SCHEMATIC DIAGRAMS
- 5.1Transmitter Block Diagram
- 5.2Transmitter Main Board Electrical Assembly
- 5.2.1Transmitter Main Board Top Side Component Layout
- 5.2.2Transmitter Main Board Bottom Side Component Layout
- 5.2.3Transmitter Main Board Schematic Diagram
- 5.3Front Panel Board
- 5.3.1Front Panel Board Component Layout
- 5.3.2Front Panel Board Schematic
- 5.4Audio Processor Electrical Assembly (Version 1.6)
- 5.4.1Audio Processor Component Layout
- 5.4.2Audio Processor Schematic Diagram
- 5.5Audio Processor Electrical Assembly (Version 1.8)
- 5.5.1Audio Processor Component Layout
- 5.5.2Audio Processor Schematic Diagram
- 6PARTS LISTS
- 6.1Transmitter Main Board Parts List
- 6.1.1Transmitter Main Board Electrical Parts List
- 6.1.2Transmitter Main Board Mechanical Parts List
- 6.1.3MT-3 Front Panel Board Electrical Parts List
- 6.2MT-3 Audio Processor Parts List (Version 1.6)
- 6.2.1MT-3 Audio Processor Electrical Parts List (Version 1.6)
- 6.3MT-3 Audio Processor Parts List (Version 1.8)
- 6.3.1MT-3 Audio Processor Electrical Parts List (Version 1.8)
- 7REVISION HISTORY
- AUDIO PROCESSOR
- 1 FM AUDIO PROCESSOR
- 2 SIGNALS
- 3 THEORY OF OPERATION
- 4 ALIGNMENT
- 5 TROUBLESHOOTING - TEST EQUIPMENT NEEDED
- 6 TEMPERATURE COMPENSATION
- 7 ILLUSTRATIONS, TABLES AND SCHEMATIC DIAGRAMS
- 8 FM AUDIO PROCESSOR PARTS LIST
- 9 AM AUDIO PROCESSOR
- 9.1 Introduction
- 9.2 Performance Specifications
- 9.3 Audio Specifications
- 9.4 Audio Circuits
- 9.5 Power Requirements
- 9.6 Transmitter Standby Modes
- 9.7 Audio Circuitry
- 9.8 AM Audio Processor Factory Configuration
- 9.9 AM Audio Processor Alignment
- 9.10 AM Audio Processor Electrical Parts List
- 9.11 AM Audio Processor Component Layout
- 9.12 AM Audio Processor Schematic Diagram
- 10 REVISION HISTORY
- VHF AMPLIFIER
- 1GENERAL
- 2THEORY OF OPERATION
- 3VT-3/150 AMPLIFIER ALIGNMENT
- 3.1General
- 3.2Repair Note
- 3.3Recommended Test Equipment List
- 3.4Printed Circuitboard Numbering Convention
- 3.5Standard Factory Settings and Jumper Configuration
- 3.6VT-3/150 Amplifier Alignment
- 3.6.1General
- 3.6.2VT-3/150 Amplifier Adjustment
- 3.6.2.1General Set-Up
- 3.6.2.2Output Power Alarm (Forward Power)
- 3.6.2.3Output Power
- 3.6.2.4Antenna VSWR Alarm (Reverse Power)
- 3.6.2.5Antenna VSWR Overload
- 3.6.2.6Procedure Verification
- 4ILLUSTRATIONS AND SCHEMATIC DIAGRAMS
- 5PARTS LISTS
- 6REVISION HISTORY
- ENHANCED AM/FM SYNTHESIZER
- 1. GENERAL
- 2. THEORY OF OPERATION
- 2.1 Internal Power and Control (Digital Board)
- 2.2 Synthesizer Analog Circuitry (Analog Board)
- 2.2.1 Common Analog Board Circuitry
- 2.2.2 29 - 71.4 MHz Analog Board Circuitry
- 2.2.3 118 - 159.4 MHz Multichannel AM Analog Board Circuitry
- 2.2.4 128 - 174 MHz Analog Board Circuitry
- 2.2.5 406 - 470 MHz Analog Board Circuitry
- 2.3 Synthesizer Digital Circuitry (Digital Board)
- 2.4 Frequency Control
- 2.4.1 BCD Switch Frequency Control
- 2.4.2 Frequency Select Handle Frequency Control
- 2.5 Synthesizer Base and Frequency Increment Table
- 2.6 5.0/6.25 kHz Channelization.
- 2.7 8.333 kHz Channelization.
- 2.8 12.5 kHz Channelization.
- 3. SYNTHESIZER ALIGNMENT
- 3.1 General
- 3.2 Repair Note
- 3.3 Recommended Test Equipment
- 3.4 OS(R/T)-3(A/H) Synthesizer Factory Configuration
- 3.5 OS(R/T)-3(A/H) Synthesizer Alignment
- 3.5.1 General
- 3.5.2 Synthesizer Test Points
- 3.5.3 Synthesizer Removal and Installation
- 3.5.4 Circuit Board Removal
- 3.5.5 Frequency Adjustment and Channel Selection
- 3.5.5.1 VHF OS(R/T)-3H 29 - 71.4 MHz VCO Alignment
- 3.5.5.2 VHF OS(R/T)-3A 118 - 159.4 MHz Alignment
- 3.5.5.3 VHF OS(R/T)-3H 128 - 174 MHz VCO Alignment
- 3.5.5.4 UHF OS(R/T)-3H 406 - 470 MHz VCO Alignment
- 3.5.5.5 Reference Frequency Alignment
- 3.5.6 Jumper Configuration
- 4. ILLUSTRATIONS AND SCHEMATIC DIAGRAMS
- 4.1 OS(R/T)-3H 29 - 71.4 MHz Analog Board Diagrams
- 4.1.1 OS(R/T)-3H 29 - 71.4 MHz Analog Board Component Layout (Bottom)
- 4.1.2 OS(R/T)-3H 29 - 71.4 MHz Analog Board Component Layout (Top)
- 4.1.3 OS(R/T)-3H 29 - 71.4 MHz Analog Board Schematic Diagram
- 4.2 OS(R/T)-3A 118 - 159.4 MHz Analog Board Diagrams
- 4.2.1 OS(R/T)-3A 118 - 159.4 MHz Analog Board Component Layout (Bottom)
- 4.2.2 OS(R/T)-3A 118 - 159.4 MHz Analog Board Component Layout (Top)
- 4.2.3 OS(R/T)-3A 118 - 159.4 MHz Analog Board Schematic Diagram
- 4.3 OS(R/T)-3H 128 - 174 MHz Analog Board Diagrams
- 4.3.1 OS(R/T)-3H 128 - 174 MHz Analog Board Component Layout (Bottom)
- 4.3.2 OS(R/T)-3H 128 - 174 MHz Analog Board Component Layout (Top)
- 4.3.3 OS(R/T)-3H 128 - 174 MHz Analog Board Schematic Diagram
- 4.4 OS(R/T)-3H 406 - 470 MHz Analog Board Diagrams
- 4.4.1 OS(R/T)-3H 406 - 470 MHz Analog Board Component Layout (Bottom)
- 4.4.2 OS(R/T)-3H 406 - 470 MHz Analog Board Component Layout (Top)
- 4.4.3 OS(R/T)-3H 406 - 470 MHz Analog Board Schematic Diagram
- 4.5 OS(R/T)-3(A/H) Digital Board Diagrams
- 4.5.1 OS(R/T)-3(A/H) Digital Board Component Layout (Bottom)
- 4.5.2 OS(R/T)-3(A/H) Digital Board Component Layout (Top)
- 4.5.3 OS(R/T)-3(A/H) Digital Board Schematic Diagram
- 5. PARTS LISTS
- 5.1 OS(R/T)-3H 29 - 71.4 MHz Analog Board Electrical Parts List
- 5.2 OS(R/T)-3A 118 - 159.4 MHz Analog Board Electrical Parts List
- 5.3 OS(R/T)-3H 128 - 174 MHz Analog Board Electrical Parts List
- 5.4 OS(R/T)-3H 406 - 470 MHz Analog Board Electrical Parts List
- 5.5 OS(R/T)-3(A/H) Digital Board Electrical Parts List
- 5.6 OS(R/T)-3(A/H) Synthesizer Mechanical Parts List
- 6. REVISION HISTORY
- VHF CHANNEL DESIGNATION TABLES
Transmitter Main Board Instruction Manual
3-5
3.6.2
MT-3 Transmitter Board Test Points
TP1:
squelched,
de-emphasized
audio /
+13.8
Vdc
TP2:
microphone
audio
TP3:
microphone
PTT WTO;
inactive
+9.5
Vdc,
active
0 Vdc
TP4:
microphone
PTT NTO;
inactive
+9.5
Vdc,
active
0 Vdc
TP5:
+9.5
Vdc from
backplane
connector
TP6:
+9.5
Vdc from front panel board
TP7:
+9.5
Vdc
Switched
TP8:
Qualified
PTT;
inactive
+9.5
Vdc,
active
0
Vdc:
activated
by synthesizer
TP9: synthesizer
enable;
selected
by J18
TP10: synthesizer bootstrap
line;
+5
Vdc
TP11: synthesizer PTT
input;
inactive
+9.5
Vdc,
active
0 Vdc
TP12: audio processor TOT
input;
inactive
+9.5
Vdc,
active
0 Vdc
TP13: audio processor TOT
output;
inactive
+9.5
Vdc,
active
0 Vdc
TP14: audio processor audio output
TP15: audio processor audio control line
TP16: audio processor subtone #2 output
TP17: audio processor
direct
modulation
input
TP18: audio processor subtone #2 input
TP19: audio processor continuous
+9.5
Vdc
TP20: audio processor subtone #1 input
TP21: audio processor supply
+8
Vdc,
selected
by J7
TP22: audio processor
tone/digital
input
TP23: synthesizer
receive
data
line;
0 Vdc
TP24: synthesizer
transmit
data
line;
+5
Vdc
TP25: Q1
collector;
inactive
0
Vdc,
active
+9.5
Vdc
TP26: U2d
output;
inactive
+9.5
Vdc,
active
0 Vdc
TP27: U1a output (PTT WTO);
inactive
+9.5
Vdc,
active
0 Vdc
TP28: U1b output (PTT NTO);
inactive
+9.5
Vdc,
active
0 Vdc
TP29: Q6
collector
/ Q7
gate;
inactive
+9.5
Vdc,
active
0 Vdc
TP30:
+9.5
Vdc PTT
Switched
TP31: U8 pin 1, Time-O
ut-Timer
circuitry
set input
TP32: U8 pin 2,
Time-Out-Timer
circuitry
reset input
TP33: Audio processor
balanced
audio input
TP34: Audio processor
balanced
audio input
3.7
Module Installation and Removal
Installation
of the
Enhanced
Synthesizer or Crystal
Controlled
Oscillator
module is
facilitated
by
alignment
pins on each corner of the module. When the four pins are
aligned
with
their
corresponding hole in the
Transmitter
Main
Board,
push the module
down,
taking care to ensure the
connector
pins on the
bottom
of the Synthesizer or Crystal
Controlled
Oscillator
module are not
bent.