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
68P81093C75-O November 30, 2000 9-41
Step 2. Remove the chassis from its case by removing the
eight Phillips screws from the edges of the station’s
top panel.
Step 3. Remove the two Torx screws from the Receiver
Module front panel and remove the four Phillips
screws. Remove the panel.
Step 4. Using the torque driver and deep-well socket, loosen
the three tension nuts on the adjustment screws.
Step 5. De-tune the preselector as follows:
Turn tuning screws 3 and 4 clockwise until they bottom
out. Be careful not to apply more than 3 in. – lb. of
torque to prevent warping the preselector cover and
housing.
Step 6. Connect the test equipment as shown in Figure 14.
Tuning Procedure Step 1. Turn the station power supply ON (to provide the
active 50 Ω termination).
Step 2. Adjust the signal generator to the frequency calculated
on page 39. Set the level to +5 dBm.
Figure 14 Test Equipment Setup for Preselector Field Tuning
From
Signal
Generator
RX
TX
Tension Nut
Tuning Screw
To Dip/Peak
Monitor
(RF Millivoltmeter
or Power Meter)
Tuning
Probe
To
Receiver
Board
To RX
Connector
on Top Panel
Preselector
Assembly
MAEPF-27040-O