An improved power supply for the AN/PRC-117G military radio has been developed. The presently disclosed power supply includes an AC-DC power conversion module; a DC-DC power module and an onboard battery backup. The disclosed power supply is an adaptable power supply which configures to provide AC-DC power; DC only power and battery backup power. The AC and DC power modules are independent and separable, and may be configured by the radio user to remove the AC module and operate in a DC only mode. The adaptability of the power supply includes universal power supply for the Harris Corporation Falcon III series of radios which includes the AN/PRC-117G; RF-7800H-MP; RF-7800M-MP; RF-7800-RC; AN/PRC-160 and the RF-7800-RT intelligence, surveillance and reconnaissance terminal.