80-G-700319:  First Rotating Beam Radar (200 megacycle radar used for transmitting and receiving) Developed by the U.S. Naval Research Laboratory (NRL) in 1937.Photograph released August 14, 1945.  U.S. Navy photograph, now in the collections of the National Archives.  Also at NHHC as NH 41640.  (2016/06/28).
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