User Manual

VT-4R150 VHF Project 25 Digital Transmitter Instruction Manual iii
TABLE OF CONTENTS
Page
1 GENERAL..................................................................................... 1-1
1.1 Introduction .............................................................................. 1-1
1.2 Interim Operation ........................................................................ 1-1
1.3 Manual Organization .................................................................... 1-1
1.4 VT-4R150 Transmitt er Family Models............................................... 1-2
1.5 Performance Specifications ............................................................ 1-2
1.5.1 General................................................................................ 1-2
1.5.2 Audio Specifications ................................................................. 1-3
1.5.3 Physical Specifications .............................................................. 1-4
2 THEORY OF OPERATION ................................................................. 2-1
2.1 General................................................................................... 2-1
2.2 Power Supply ........................................................................... 2-1
2.3 High Speed Serial Interconnect ........................................................ 2-2
2.4 Audio Circuits ........................................................................... 2-2
2.5 PTT Circuitry ............................................................................ 2-2
2.6 Microprocessor Board.................................................................. 2-2
2.7 Channel and Bank Selection ........................................................... 2-2
2.7.1 Channel Select Line Mapping....................................................... 2-3
2.8 Jumper Functions and standard configuration ....................................... 2-3
2.9 Hang Timer Selection ................................................................... 2-4
2.10 Kerchunk noise selection ............................................................... 2-5
2.11 Test Points ............................................................................... 2-5
2.12 Connector Pinouts ...................................................................... 2-6
2.12.1 Connector J9.......................................................................... 2-6
2.12.2 Connector P1 ......................................................................... 2-6
2.13 Transmitter Programming.............................................................. 2-6
2.13.1 Transmitter Wide Options ........................................................... 2-7
2.13.1.1 Frequency Band ................................................................. 2-7
2.13.1.2 Source ID......................................................................... 2-7
2.13.1.3 Secure Hardware Equipped .................................................... 2-7
2.13.1.4 Timeout Options ................................................................. 2-7
2.13.2 Channel Wide Settings .............................................................. 2-8
2.13.2.1 Channel Name ................................................................... 2-8
2.13.2.2 Frequency ........................................................................ 2-8
2.13.2.3 Analog Bandwidth............................................................... 2-8
2.13.2.4 Deviation .......................................................................... 2-8
2.13.2.5 Channel Type .................................................................... 2-8
2.13.2.6 Audio Pre-emphasis............................................................. 2-9
2.13.2.7 Timeout Value .................................................................... 2-9
2.13.2.8 Project 25 Squelch Settings: Network Access Code (NAC) ............... 2-9
2.13.2.9 Project 25 Squelch Settings: Talk Group ID (TGID)........................ 2-9