User Manual
Table Of Contents
- 1. INTRODUCTION
- 1.1. Scope and Purpose of Document
- 1.2. Limitation of Liability Notice
- 2. SAFETY CONSIDERATIONS
- 3. EQUIPMENT OVERVIEW
- 4. UHF BANDSELECTIVE, BDA (55-199102) SUB MODULES
- 4.1. Bandpass Filter (02-010701)
- 4.2. 3dB Splitter/Combiner (05-002603)
- 4.3. Remote Attenuator Switch Assembly (‘10-001725’)
- 4.4. 5 Watt Tetra Amplifier (12-021601)
- 4.5. Linearised Power Amplifier (12-026901)
- _
- 4.6. Voltage Regulator Board 9.0V (13-001714)
- 4.7. DC/DC Converter, 24V in, 12V 8A out (13-003011)
- 4.8. Bi-Directional Amplifier (17-017301)
- 4.9. 12V (Single) Relay Board (80-008901)
- 4.10. 24V Switch-Mode PSU (96-300054)
- 5. INSTALLATION & COMMISIONING
- 6. FAULT FINDING / MAINTENANCE
- 6.1. Tools & Test Equipment
- 6.2. Basic Fault Finding
- 6.3. Quick Fault Checklist
- 6.4. Downlink
- 6.5. Uplink
- 6.6. Fault repair
- 6.7. Service Support
- 6.8. Care of Modules
- 6.9. Module Removal (LNAs, general procedure):
- 6.10. Module Replacement (general):
- 6.11. Power Amplifiers
- 6.12. Low Power Amplifier Replacement
- 6.13. Module Transportation:
- APPENDIX A
- _
- _
- APPENDIX B
UHF Bandselective BDA
90dB 40/5W
Document Number 55-199102HBKM Issue No. 1 Page 12 of 28
4. UHF BANDSELECTIVE, BDA (55-199102) SUB MODULES
4.1. Bandpass Filter (02-010701)
The bandpass filters are multi-section designs with a bandwidth dependent upon the passband
frequencies, (both tuned to customer requirements). The response shape is basically Chebyshev with
a passband design ripple of 0.1dB. The filters are of combline design, and are carefully aligned during
manufacture in order to optimise the insertion loss, VSWR and intermodulation characteristics of the
unit. The tuned elements are silver-plated to reduce surface ohmic losses and maintain a good VSWR
figure and 50 load at the input and output ports.
Being passive devices, the bandpass filters should have an extremely long operational life and require
no maintenance. Should a filter be suspect, it is usually most time efficient to replace the module
rather than attempt repair or re-tuning.
02-010701 Specification
PARAMETER SPECIFICATION
Response type: Chebyshev
415 - 418MHz (uplink)
Frequency range:
406 - 409MHz (downlink)
Bandwidth: 3 MHz
Number of sections: 5
Insertion loss: 1.7 dB (typical)
VSWR: better than 1.2:1
Connectors: SMA
Power Handling: 100W max
operation: -20°C to +60°C
Temperature range
storage: -40°C to +70°C
Weight: 3 kg (typical)