User Manual
STTRS DOCUMENTATION
Document Number 80-330501HBKM – Issue A - Draft Page 476 of 500
Low Power Amplifier (12-021901) 7-Way Connector Pin-outs
Connector Pin Signal
A1 (large pin) +24V DC
A2 (large pin) GND
1 Alarm relay common
2 TTL alarm/0V good
3 Alarm relay contact (bad)
4 Alarm relay contact (good)
5 O/C good/0V bad (TTL)
25.3.2.6. DC/DC Converter 13-003412
13-003412 is based upon an O.E.M. DC/DC Converter module with a wide input range and and is
used to derive a 12V fixed voltage power supply rail from a higher voltage supply, in this case 24V. In
the event of failure this unit should not be repaired, only replaced.
13-003412 Specification
PARAMETER SPECIFICATION
Operating voltage 18 – 75V DC
Output voltages 12V (typical)
Output current 5.0A (Max)
operational -10%C to +60%C Temperature
range
storage -20%C to +70%C
25.3.2.7. AGC System
AGC Detector Unit (17-001109)
AGC Attenuator Unit (17-001201)
Equipment 700MHz Uplink Amplifier (50-132107) is fitted with a wide dynamic range Automatic Gain
Control (AGC) system. This is fitted in the Uplink path to avoid overloading the amplifiers (with the
associated performance degradation) should a mobile be operated very close to the unit.
The AFL wide dynamic range Automatic Gain Control system consists of two units, a
detector/amplifier and an attenuator. The logarithmic detector/amplifier unit is inserted in the RF path
on the output of the power amplifier, and the attenuator is situated in the RF path between the 1st and
2nd stages of amplification.