Signal Corps Radio

Signal Corps Radios were U.S. Army military communications components that comprised "sets". Under the Army Nomenclature System, SCR initially designated "Set, Complete Radio", and later misinterpreted as "Signal Corps Radio", though interpretations have varied over time.

The term SCR was part of a nomenclature system developed for the U.S. Signal Corps, used at least as far back as World War I. Three-letter designators beginning with "SC" were used to denote complete systems, while one and two-letter designators (such as "BC", for basic component, "FT" for mounting, etc.) were used for components. Only a few system designators were used:

The U.S. Signal Corps used the term "sets" to denote specific groupings of individual components such as transmitters, receivers, power supplies, handsets, cases, and antennas. SCR radio sets ranged from the relatively small SCR-536 "handie talkie" to high-powered, truck-mounted mobile communications systems like the SCR-299 and large microwave radar systems such as the SCR-584 radar.

The SCS designator was applied to groups of SCR-numbered sets comprising an extensive system, such as multiple radio sets employed in a ground-based fighter direction/control center. The SCR designator could be a single transmitting or receiving set, or a full set of both transmitting and receiving equipment.

An additional designator, "RC" was used for subsystems or groups of accessories. The Joint Electronics Type Designation System which came into use in 1943 absorbed or superseded the SC designations.

This is only a general list, quite a few radios crossed over between branches.

Armor

Artillery

Infantry

general use/command

Cavalry

Coast artillery/AAA

Air Liaison (ground)

Aircraft

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