Introduced in 1940, it was developed to provide accurate aiming information for antiaircraft artillery and was also used for gun laying systems and directing searchlights against aircraft.

The radar was widely utilized by both Army and Marine Corps air defense and early warning units during World War II.

While most of the Corps' efforts revolved around infra-red detection systems (a popular idea at the time), as well as a newer generation of sound detectors, they also maintained a small program of research on microwave radars based on the "beat principle", in which an aircraft would cause two signals to interfere.

The navy's system traced its development from experiments conducted by Albert H. Taylor and Leo C. Young at the United States Naval Research Laboratory in the early 1920s.

They decided to try to find a need for such a unit in order to gain funding, and eventually received a "request" by the Chief of Coast Artillery on February 1, 1936 for a gunlaying system with a range of 15,000 yards through rain, mist, smoke or fog.

Gaining the support of James B. Allison, the Chief Signal Officer, they managed to gather a small amount of funding and "stole" some more from other projects.

Development of this system was slowed to some degree when a long range early-warning radar became a higher priority and parts of the prototype were salvaged for the SCR-270 they were building.

The SCR-268 antenna system consisted of a number of dipole elements arranged in three groups, each in front of a passive reflector, mounted on a large aimable cross.

Finally in the "middle" of the cross, between the upright pedestal and the elevation antenna, was the broadcasting array which created a circular beam about 10 degrees wide.

Range information was taken from the elevation array, and worked, as it did for most radars of the era, by triggering the trace on an "A-line" oscilloscope and read against a scale at the bottom.

This system was eclipsed by the SCR-584, which utilized a 3 GHz magnetron oscillator from Britain, completely automatic tracking, and the Bell Telephone Laboratories electronic M9 gun director.