User's Manual

iii

8/30/02 68P81095E05-C

Module Replacement Procedures page 19..............................................

General Replacement Information page 19......................................................

Replacing Power Amplifier Module page 21.....................................................

Replacing Exciter Module page 22.............................................................

Replacing Power Supply Module page 23.......................................................

Replacing Station Control Module page 24......................................................

Replacing Wireline Interface Board page 30.....................................................

Replacing Receiver Module and/or Preselector Assembly (VHF and UHF) page 32...................

Replacing Receiver Module (800 MHz and 900 MHz) page 33.....................................

Replacing ASTRO Modem Card page 34........................................................

Replacing Backplane Board page 35...........................................................

Preselector Field Tuning Procedure page 36............................................

Required Test Equipment page 36.............................................................

VHF Tuning Procedure page 37...............................................................

UHF Tuning Procedure page 40...............................................................

STATION MODULES

RECEIVER CIRCUITRY

RECEIVER MODULE (VHF Ranges 1 and 2; Includes Preselector) 68P81086E28.........

Description page 1....................................................................

General Description page 1....................................................................

Overview of Circuitry page 1...................................................................

Controls, Indicators, and Inputs/Outputs page 2........................................

Functional Theory of Operation page 3.................................................

Synthesizer and VCO Circuitry page 3...........................................................

Preselector Filter Assembly page 4.............................................................

Receiver Front End Circuitry page 4.............................................................

Custom Receiver IC Circuitry page 4............................................................

Address Decode and A/D Converter Circuitry page 5..............................................

Voltage Regulator Circuitry page 5..............................................................

RECEIVER MODULE (UHF) 68P81086E48.............................................