Operating instructions

Table of Contents DMH Series VHF Radio
Page iv BK RADIO
4.3 THEORY OF OPERATION........................................................................................................... 4-2
4.3.1 SYSTEM BOARD................................................................................................................... 4-2
4.3.2 RX/TX BOARD....................................................................................................................... 4-3
4.3.3 HIGH LEVEL PA BOARD.......................................................................................................4-4
4.3.4 OPTIONS BOARD ................................................................................................................. 4-5
4.3.5 CONTROL BOARD................................................................................................................ 4-5
4.3.6 VCO BOARD.......................................................................................................................... 4-5
SECTION V
MAINTENANCE
5.1 INTRODUCTION .......................................................................................................................... 5-1
5.2 TEST EQUIPMENT REQUIRED............................................................................................ 5-1
5.3 OVERHAUL .................................................................................................................................. 5-1
5.3.1 ACCESSORIES ..................................................................................................................... 5-1
5.3.2 CLEANING............................................................................................................................. 5-3
5.3.3 REPAIR.................................................................................................................................. 5-3
5.4 DISASSEMBLY & ASSEMBLY..................................................................................................... 5-4
5.4.1 UNIT DISASSEMBLY............................................................................................................. 5-4
5.4.2 CONTROL HEAD ASSEMBLY .............................................................................................. 5-4
5.4.2.1 CONTROL BOARD................................................................................................ 5-5
5.4.2.2 DISPLAY BOARD .................................................................................................. 5-5
5.4.2.3 PUSHBUTTON LABELS........................................................................................ 5-5
5.4.2.4 RECONNECT CONTROL HEAD .......................................................................... 5-5
5.4.3 CORE ASSEMBLY................................................................................................................. 5-6
5.4.3.1 VCO AND RX/TX BOARDS................................................................................... 5-6
5.4.3.2 VCO AND RX/TX REASSEMBLY.......................................................................... 5-6
5.4.3.3 SYSTEM BOARD .................................................................................................. 5-6
5.4.3.4 SYSTEM BOARD REASSEMBLY ......................................................................... 5-6
5.4.4 THE PA ASSEMBLY.............................................................................................................. 5-7
5.4.5 UNIT ASSEMBLY................................................................................................................... 5-7
5.5 ALIGNMENT PROCEDURES ...................................................................................................... 5-7
5.5.1 TEST SETUP......................................................................................................................... 5-7
5.5.2 ALIGNMENT ORDER ............................................................................................................ 5-7