Ground Controlled Intercept (GCI)
Type 60 and 61 GCI
The photograph caption reads:
Bell Telephone Laboratories developed this radar that subsequently was produced by the Western Electric Company. A crew of two could operate the radar. The lB model could detect bombers at 10,000 feet at a distance of 120 nautical miles. The height detection and range on the 1C and 1D models exceeded those of the lB. The transmitter sent its pulse at an L-band frequency between 1220 to 1280 megahertz (MHz). In the United States this long-range search radar was used in the temporary "Lashup" system beginning in 1948. (Searching The Skies). In R.A.F. service the 1A model was called Type 61 Mk.1, the 1b was Type 61 Mk.2.
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. (Searching The Skies). In R.A.F. service the 10 model was called Type 60. In common with other height finders this radar featured an antenna that was nodded up and down, which led to it being nicknamed "Lil' Abner" after the U.S. cartoon character who rocked back and forth in a rocking chair.
Technical Specs: (Radio Research catalog)
X-Band Height Finder Radar type: AN/TPS-10D.
RHI 12" CRT Range 0-60,000 ft. 200 miles. Input: 115V 400cycles AC. Mfr: RCA type AN/TPS-10D Radar.
I do not have much information on how these radars were used in R.A.F.service or how the R.A.F. came by them. In "Watching The Skies" Jack Gough mentions that an AN/TPS-1b was purchased from the U.S. in 1949 in order to aid British L-Band radar developments (page 66).
One interesting point to note about the U.S. site in the sketch above, the buildings appear to be made from wood - a far cry from the hardened shelters and earth revetments we were used to in the U.K.!
Constructed by Dick Barrett