Trunk line amplifier ULM

Technical parameters


The trunk line amplifier is designed to compensate for attenuation and additional amplification of signals in creating four-wire channels for long-distance intercom, dispatching communication and telemechanics. The amplifier is designed for operation at intermediate and end points with placement in communication centers and in unattended repeater stations (URS).


  • Receiving, amplification and transmission of signals (transit) at intermediate points in the trunk communication line;
  • Two auxiliary amplifier channels for combining two trunks or connecting an intercom;
  • The capability of stepwise gain compensation and frequency equalization at high frequencies;
  • The capability to control the signal levels in the two main channels using the built-in LED indicator;
  • Monitoring the presence of the input;
  • The capability to connect to a remote power supply.

Technical parameters

Number of amplifier channels, main/auxiliary 2/2
Output levels 0/-13 dB
Stepwise gain compensation, minimum 35 dB
Power supply voltage 21 to 27 V
Power consumption 10 W
Dimensions, WxHxD 330x47x175 mm
Weight 1.5 kg