MIT's Radiation Laboratory developed and produced the first version of this radar
near the end of World War II. Zenith produced the A-model sets in the post-war period.
The vertically mounted antenna was three feet wide and ten feet long. Two operators
were needed to run the set. The initial model operated at a frequency of 9000 to 9160
MHz and had a maximum reliable range for bombers of 60 miles at 10,000 feet.
An updated version designated the AN/FPS-4 was produced by the Radio Corporation of America (RCA) beginning in 1948. Some 450 copies of this and the trailer-mounted AN/MPS-8 version were built between 1948 and 1955.
Technical Specs: (Radio Research catalog)
RHI 12" CRT Range 0-60,000 ft. 200 miles. Input: !15V 400cy AC. Mfr: RCA type AN/TPS-10D Radar.