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 6 of 28
3. EQUIPMENT OVERVIEW
The AFL UHF Bandselective, Bi-Directional Amplifier (BDA) (55-199102) is a 2-way on-band repeater.
The equipment is supplied in a four-point, wall-mounting, environmentally protected (IP65) aluminium
alloy lockable case. All RF ports and connectors are also IP65 standard making the entire enclosure
and connecting ports weatherproof. Handles are provided for carrying the unit and the door is fitted
with locks. A supply isolator switch is fitted inside the unit and there are D.C. and Alarm On indicators
on the outside of the door.
The UHF Bandselective, BDA (55-199102) is a 2-port device for direct connection to two antennas,
usually a highly directional Yagi or similar aligned towards the base (donor) site and an omni-
directional or leaky feeder antenna to cover the mobiles. The frequency bands that are passed by the
BDA are set as per the specific customer requirements.
Each active sub-module of the BDA carries its own volt-free, alarm relay contact interface which may
be easily integrated into any such summary system. In addition to this, over temperature and door
intrusion alarms are also fitted.
The Uplink signal enters at the ‘Mobile’ port, passes through a bandpass filter (02-010701) tuned to
the uplink band (415 - 418MHz) and then is amplified by the uplink path of Bi-Directional Amplifier
(17-017301) before passing through a second bandpass filter (02-010701)
The signal then passes through a second amplification stage (30dB gain 5Watt,), the signal then
passes through a third bandpass filter (02-010701) before exiting the unit at the ‘Base’ port
The Downlink signal enters at the ‘Base’ port and is passed through a bandpass filter (02-010701)
tuned to the downlink band (406 - 409MHz), the signal then passes through the downlink path of Bi-
Directional Amplifier (17-017301) and a second bandpass filter (02-010701) before being split into two
equal paths by 3dB Splitter/Combiner (05-002603). Each separate path is then passed through a
further amplification stage, each path pasing through a Linearised Power Amplifier (12-026901). After
exiting the amplifiers the two separate signals are recombined by a second 3dB Splitter/Combiner
(05-002603) before passing through a third bandpass filter (02-010701) and then exiting the unit at
the "mobile" port
The uplink and the downlink paths are fitted with signal attenuators providing an attenuation range of
0 to 30 dB per path, adjustable in 2dB steps. The attenuators themselves are integral to the sub
module Bi-Directional Amplifier (17-017301) and are controlled by toggle switches mounted inside the
case of the Bandselective, BDA (55-199102)