The AM-2060(*)/GRC is the main component of the OA-3633(*)/GRC; the other component is Cable Assembly, Special Purpose, Electrical CX-4656/GRC, The CX-4656/GRC provides dc power and audio signal connection between the receiver-transmitter and the AM-2060 (*)/GRC. The AM-2060(*)/GRC converts vehicular battery power (24 ±3 volts dc) to the operating voltages for the receiver-transmitter, and amplification of the receiver-transmitter received audio signals for application to the loudspeaker in the AM–2060(*)/GRC, and to the crewmember control boxes when they are a part of the system VIC1. The vehicular battery power is also applied to Antenna Matching Unit MX–2799/VRC (part of Antenna AT-912/VRC) or to Matching Unit-Base, Antenna MX-6707/VRC (part of Antenna AS-1729/VRC).