World War II-era AN/PRC-5 radio set used for clandestine communication amongst spies and for military purposes. The portable radio set is housed in a suitcase, measuring 12.5″ x 11″ x 5.5″, with a schematic diagram inside the lid. The transmitter covers 4 to 16 mHz in four bands, and the receiver covers 4.5 to 16 mHz in two bands.
The War Department's technical manual for the radio (TM11-265), issued in June 1944 and classified as secret, remained so for forty years until its declassification in 1984. The manual defines the radio set as follows: Radio Set AN/PRC-5 is designed for shortwave communication over medium distances from variable points. It is a portable transceiver, the component parts of which are a radio telegraph transmitter, a radio receiver, and a power supply unit common to both. All three are constructed in one unit which is mounted in a luggage-type carrying case, designed to house the radio's peripherals and accessories.
The transmitter is of the radio-telegraph type, with a power output of 16 watts when the output frequency is the same as that of the crystal, and an output of 10 watts when the output frequency is twice that of the crystal. The transmitter is composed of two stages: a crystal-controlled oscillator stage followed by a power-amplifier stage. Both of these stages are keyed during periods of transmission. The receiver is of the superheterodyne type.
