User Manual
Table Of Contents
- AMENDMENT LIST RECORD SHEET
- INTRODUCTION
- 1.SAFETY CONSIDERATIONS
- 2.OVERVIEW/SYSTEM DESCRIPTION
- 3.SPECIFICATION
- 4.SYSTEM DRAWINGS
- 5.SUB-UNIT MODULES
- 5.1Downlink Channelised Cell Enhancer 60-060602 (5U chassis)
- 5.1.1Bandpass Filters (02-010701)
- 5.1.2UHF 3dB Splitter (05-002603)
- 5.1.33dB UHF Splitter (05-002603)
- 5.1.4¼Watt 0- -30dB Switched Attenuator \(10-00
- 5.1.5Low Noise Amplifiers (11-007302 & 11-007402)
- 5.1.5.1Description
- 5.1.5.2Technical Specification, (11-007302)
- 5.1.5.3Technical Specification (11-007402)
- 5.1.5.3Drg. No. 11-007302, LNA Assembly With Alarm Relay
- 5.1.5.4Drg. No. 11-007370, LNA RF Circuit Diagram
- 5.1.5.5Drg. No. 11-007371, LNA DC Wiring Diagram
- 5.1.5.6Drg. No. 11-003971, LNA DC Circuit Diagram
- 5.1.610Watt Power Amplifier (12-001901)
- 5.1.73 Stage Amplifier Alarm Boards (12-002201)
- 5.1.8Dual DC/DC Converter (13-001803)
- 5.1.9Channel Selective Module (17-003012)
- 5.1.1024V Relay Board (20-001602)
- 5.2Uplink Channelised Cell Enhancer 50-060603 (5U chassis)
- 5.3Power Supply Shelf 50-060604 (4U chassis)
- 5.1Downlink Channelised Cell Enhancer 60-060602 (5U chassis)
- 6.INSTALLATION
- 7.MAINTENANCE
- APPENDIX AINITIAL EQUIPMENT SET-UP CALCULATIONS

5-Way Channelised UHF Cell Enhancer
Maintenance Handbook
H/book Number:-50-060601HBKM
Issue No:-
1
Date:-04/07/2003
Page:-
21 of 54
5.1.3 3dB UHF Splitter (05-002603)
5.1.3.1 Description
The 3dB Splitter/Combiner used is a device for accurately matching two or more RF
signals to single or multiple ports, whilst maintaining an accurate 50Ω load to all
inputs/outputs and ensuring that the VSWR and insertion losses are kept to a minimum.
Any unused ports will be terminated with an appropriate 50Ω load.
5.1.3.2 Technical Specification
PARAMETER SPECIFICATION
Frequency Range:
400-500 MHz
Power Rating: 5 Watts
Insertion Loss: 5.2dB Typical
VSWR: 1.2:1
Impedance: 50 Ohms
Connectors: SMA
Weight: <0.5Kgs
Mechanical: Drawing No. 07-003890
5.1.4 ¼Watt 0- -30dB Switched Attenuator (10-000701)
5.1.4.1 General Application
In many practical applications for Cell Enhancers etc., the gain in each path is found to be
excessive. Therefore, provision is made within the unit for the setting of attenuation in
each path, to reduce the gain.
5.1.4.2 Switched Attenuators
The AFL switched attenuators are available in two different types; 0 – 30dB in 2 dB steps
(as in this case), or 0 – 15dB in 1 dB steps. The attenuation is simply set using the four
miniature toggle switches on the top of each unit. Each switch is clearly marked with the
attenuation it provides, and the total attenuation in line is the sum of the values switched
in. They are designed to maintain an accurate 50 impedance over their operating
frequency at both input and output.