AN/ARC-45

Communication.

VINTAGE AVIONICS

AN/ARC-45 UHF LIAISON SET

RT-295A / ARC-45

Also known as RTA-45

The Radio Set AN/ARC-45 is a lightweight UHF airborne radio set designed for use in aircraft (mainly helicopters) for air to-air and air-to-ground communications. The ARC-45 and RTA45 were built by Bendix Radio, the RTA45 (shown) was also built in 1960 by Telefunken. The unit is a look-alike of the ARC-44, and uses the same cable loom, dynamotor and intercom panel.

The AN/ARC-45 is capable of AM transmitting and receiving on 12 preset channels within the frequency range of 225.0 to 399.9 MHz, in a 100 kHz, grid.

The RF output power is 2 watts .

Input power requirement is 28 Vdc at 4 amps both at transmit and receive. Heaters take 1.7A, tuning motor or T/R relay do 0.7A, and the external dynamotor requires up to 3A to produce +150V/90mA for all tubes except the modulator and RF power stage which runs from 300V at 70mA, when transmitting. The fan inside the ARC-45 is a 27Vac, 3-phase 400Hz type, supplied from the dedicated stator in the DY107 dynamotor.

The unit has 32 tubes, no transistors and one diode.

The circuit diagram is here

Components:

System ARC-45 or RTA-45

Transceiver RT 295A

Control SB-328

Dynamotor DY 107

Test unit ARM-8