The ARC CESSNA RT-385A NAV/COM Receiver-Transmitter is a panel-mounted solid-state unit which includes a VHF communications receiver and transmitter, a VHF navigation receiver, and a seven channel speaker amplifier. Both the communication and navigation operating frequencies are digitally displayed by incandescent readouts on the front panel. Brightness of the display is controlled by the aircraft dimmer control.

The navigation receiver processes frequencies from 108.00 to 117.95 MHz in 50 kHz steps. The receiver uses a single-crystal, phase-locked loop frequency synthesizer to cover the 200 navigation channels. The communications receiver-transmitter receives and transmits signals from 118.000 to 135.975 MHz in 25 kHz steps. The receiver-transmitter uses a single-crystal, phase-locked loop frequency synthesizer to provide frequency control for reception and transmission of 720 communications channels.