iv Table of Contents
Chapter 3 Basic Theory of Operation ................................................. 3-1
3.1 Major Assemblies........................................................................................................................... 3-2
3.2 Analog Mode of Operation ............................................................................................................. 3-3
3.3 Digital (ASTRO) Mode of Operation .............................................................................................. 3-9
3.4 Controller Section .......................................................................................................................... 3-9
Chapter 4 Recommended Test Equipment and Service Aids .......... 4-1
4.1 Recommended Test Equipment .................................................................................................... 4-1
4.2 Service Aids ................................................................................................................................... 4-2
4.3 Field Programming......................................................................................................................... 4-2
Chapter 5 Performance Checks .......................................................... 5-1
5.1 Test Equipment Setup ................................................................................................................... 5-1
5.2 Display Radio Test Mode............................................................................................................... 5-3
5.3 Receiver Performance Checks ...................................................................................................... 5-8
5.4 Transmitter Performance Checks ................................................................................................ 5-10
Chapter 6 Radio Alignment Procedures............................................. 6-1
6.1 Test Setup...................................................................................................................................... 6-1
6.2 Tuner Main Menu........................................................................................................................... 6-2
6.3 Softpot............................................................................................................................................ 6-2
6.4 Radio Information........................................................................................................................... 6-4
6.5 Transmitter Alignments .................................................................................................................. 6-4
6.6 Front End Filter Alignment ........................................................................................................... 6-22
6.7 Performance Testing.................................................................................................................... 6-23
Chapter 7 Encryption ........................................................................... 7-1
7.1 Load an Encryption Key................................................................................................................. 7-1
7.2 Multikey Feature ............................................................................................................................ 7-2
7.3 Select an Encryption Key............................................................................................................... 7-2
7.4 Select an Encryption Index ............................................................................................................ 7-3
7.5 Erase an Encryption Key ............................................................................................................... 7-4
Chapter 8 Disassembly/Reassembly Procedures ............................. 8-1
8.1 APX 2000/ APX 4000/ APX 4000Li Exploded View (Main Subassemblies) .................................. 8-1
8.2 Required Tools and Supplies......................................................................................................... 8-3
8.3 Fastener Torque Chart................................................................................................................... 8-3
8.4 Radio Disassembly ........................................................................................................................ 8-4
8.5 Serviceable Components of the Main Sub-Assemblies ............................................................... 8-15
8.6 Radio Reassembly....................................................................................................................... 8-20
8.7 Ensuring Radio Submergibility..................................................................................................... 8-30