AN/FPS-23
The Motorola AN/FPS-23 was a short-range search radar deployed to the Distant Early Warning Line (DEW Line) "Intermediate" sites as gap-fillers between the long-range AN/FPS-19 Main and Auxiliary stations.
The AN/FPS-23 DEW-Line radar system was manufactured by Motorola, and operated at frequencies between 475 and 525 MHz, with 1 kilowatt of output power. AN/FPS-23 radars were continuous wave (CW) systems composed of geographically-separated AN/FPT-4 Fluttar Transmitters and AN/FPR-2 Fluttar Receivers. AN/FPT-4 Fluttar Transmitters were located only at Intermediate ("I") Sites, while AN/FPR-2 Fluttar Receivers were located only at Main and Auxiliary Sites. The transmitters and receivers were typically about fifty miles apart. The function of this Doppler-effect detection system was to fill the low-altitude gaps between AN/FPS-19 radars located at Main and Auxiliary DEW-Line Sites.
It was declared obsolete in 1963, and the Intermediate stations were closed.
References
This article incorporates public domain material from websites or documents of the Air Force Historical Research Agency.