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
9-20 December 1, 2000 68P81093C75-O
Step 11. Measure the 12dB SINAD sensitivity and make a note
of the level. This level will serve as a baseline for the
receiver sensitivity. If 12 dB SINAD cannot be
achieved, suspect the following:
• Test configuration used does not match that shown
in Figure 8B.
• Excessive loss in the coaxial cables or coupler.
Step 12. Remove the cable connecting the coupler to the top
panel receive port. Connect the coupler to the
duplexer’s antenna port. Connect the duplexer’s
receive port to the station’s top panel receive port, as
in normal station operation. (See Figure 8B.)
Step 13. Measure the 12 dB SINAD once again, and note the
result. The difference between this 12 dB SINAD level
and the level measured in Step 11 reflects the insertion
loss of the duplexer. The difference should be no
greater than approximately
• VHF: 1.3 dB
• UHF: 1.6 dB
If the difference is greater, suspect the following:
• Duplexer receive and transmit ports are reversed
• Loose or damaged cables between the duplexer
and the station
• Station receive frequency does not match the
duplexer receive frequency. Use a different
frequency or replace the duplexer. (Field tuning of
duplexers is not recommended.)
Figure 9 Disabling the Transmitter
Press and hold
Shift Button.
Station Control
Module
Exciter
Module
MAEPF-27037-O
1
Press Vol Down/
Access Disable
2
Intcm/Acc D LED
should Flash yellow.
3
PA Full LED should
NOT illuminate.
4