Rotor radar system
AN/FPS-3
This
U.S. built AN/FPS-3 L-band centimetric radar had a range of around 200 miles.
The size of the antenna may be judged from the height of the man standing on
the right of the access platform. The AN/FPS-3 was a modified version of the
AN/CPS-5 long-range search radar. The first units came off the Bendix production
line and were ready for installation in the US in late 1950.
The AN/FPS-3B incorporated an AN/GPA-27, which increased the search altitude to 65,000 feet. In the US installation of these modifications began in 1957. (Searching The Skies)
My
thanks go out to Don Helgeson, of Evanston, Illinois, USA who kindly provided
the following information:
The Bendix AN/FPS-3 was a dual beam radar that used a pair of 5J26 Magnetrons with 750kW peak power. Unlike the DC variable drive of the AN/CPS-5 or AN/FPS-8, the AN/FPS-3 antenna rotated at fixed speeds of: 3.3, 5 or 10 RPM. 5 RPM seemed to be the best speed with the MTI prf of 400 pps. The two transmitter cubicles, the dual modulator and the common HV supply were mounted on the antenna framework. Slip rings fed power and control up and 30 MHz IF from the AM-4232 pre-amplifier down to the main console near the operations room. The AN/'MPS-7 was a mobile version of the AN/FPS-3.
