User's Manual

Weehawken Tunnel 900MHz Pager System
User/Maintenance Handbook
Handbook N.-Weehawken_900 Issue No:-A
Date:-05/08/05
Page:-
31 of 50
6.5 Low Noise Amplifier (11-005902)
6.5.1 Description
The Gallium-Arsenide low noise amplifier used in the unit is a double stage, solid-state low
noise amplifier. Class A circuitry is used throughout the units to ensure excellent linearity and
extremely low noise over a very wide dynamic range. The active devices are very moderately
rated to provide a long trouble-free working life. There are no adjustments on these amplifiers,
and in the unlikely event of a failure, then the complete amplifier should be replaced. This
amplifier features its own in-built alarm system which gives a volt-free relay contact type alarm
that is easily integrated into the main alarm system.
6.5.2 Technical Specification
PARAMETER SPECIFICATION
Frequency range: 800 – 960MHz
Bandwidth: <170MHz
Gain: 19.5dB (typical)
1dB Compression point: 21dBm
OIP3: 33dBm
Input/Output Return Loss: >20dB
Noise Figure: 1dB (typical)
Power consumption: 190mA @ 24V DC
Supply voltage: 10-24V DC
Connectors: SMA female
operational: -10°C to +60°C
Temperature range:
storage: -20°C to +70°C
Size: 90 x 55 x 30.2mm
Weight: 0.28kg
6.5.3 LNA ‘D’ Connector Pin-out details
Connector pin Signal
1 +Ve input (10-24V)
2 GND
3 Alarm Relay O/P bad
4 Alarm Relay common
5 Alarm Relay good
6 No connection
7 TTL voltage set
8 TTL alarm/0V (good)
9 O/C good/0V bad