User's Manual
Table Of Contents
- Front Cover
- Contents
- 1 - Foreword 11
- 2 - Safety and General Information 21
- 3 - Introduction 31
- 4 - System Applications 41
- 5 - Models and Specifications 51
- 6 - Approved Accessories 61
- 7 - Setup and Connections 71
- 8 - Operation 81
- 9 - Troubleshooting 91
- Introduction 91
- Recommended Test Equipment 91
- Troubleshooting Procedures 91
- Module Replacement Procedures 925
- General Replacement Information 925
- Anti-Static Precaution 925
- Care of Gold-Plated Connector Contacts 926
- Power Down Station Before Removing/Inserting Modules 926
- Validating Repairs 926
- Module Replacement 926
- Wireline 928
- ASTRO Modem Card/V.24 Interface Card 929
- Receiver 929
- Exciter 931
- Power Amplifier 932
- Power Supply 933
- Backplane 934
- Preselector Field Tuning Procedure 935
- 10 - Functional Theory of Operation 101
- 11 - Block Diagram, Schematics, Electrical Parts List, and Circuit Board Detail 111
- List of Tables
- List of Figures
- Parts Lists
- Foreword
- Safety and General Information
- Introduction
- System Applications
- Models and Specifications
- Approved Accessories
- Setup and Connections
- Operation
- Troubleshooting
- Introduction
- Recommended Test Equipment
- Troubleshooting Procedures
- Module Replacement Procedures
- Preselector Field Tuning Procedure
- Functional Theory of Operation
- Schematics
- Back Cover
9-22 December 1, 2000 68P81093C75-O
The transmitter circuitry is exercised by injecting and measuring
signals using a Motorola R2670 Communications Analyzer (or
equivalent), and analyzing the Bit Error Rate using the RSS.
Measured values outside the acceptable range indicate a faulty
module; values within range verify proper operation of the above
modules and circuitry.
Required Test Equipment The following test equipment is required to perform the procedure:
• Motorola R2670 Communications Analyzer with
ASTRO CAI Option (or equivalent)
• PC running Radio Service Software (RSS)
program
• Female N-type to Female N-type coaxial cable
• Dummy Load (50Ω, station wattage, or higher).
Required for repeater stations only.
IMPOR
TANT! If the station operates as a repeater, the transmit output from
the station must be connected to a dummy load to prevent over-
the-air broadcast during receiver testing.
Step 1. Proceed to ASTRO Bit Error Rate Report (located in
Chapter 4 of the RSS User’s Guide, part number
68P81085E35). Follow the instructions for setting up
the test equipment and initiating a BER report using
the RSS.
Step 2. If the BER reading is above 5%, suspect the
following:
• Faulty Station Control Module (2.1 MHz
reference)
• Faulty Receiver Module
• Faulty antenna-to-receiver preselector RF cable
• Faulty top panel-to-preselector RF cable
• Faulty R2670-to-station RF cable
Step 3. If you are injecting RF directly into the top panel
receiver port, change the R2670 injection signal level
to:
• VHF: 0.25 µV (-119 dBm)
• UHF: 0.35 µV (-116 dBm)
If you are injecting RF through a duplexer, change the
R2670 injection signal level to: