A starry-eyed few thousand owners of the latest fangled radio sets in areas around New York City, Boston, Washington, Columbus (Ohio), Chicago and Milwaukee, nowadays enjoy radio entertainment that is ...

FREQUENCY-MODULATION, or the technique of varying the frequency of radio waves for signalling purposes, has been known and used for many years ; but it was not until Armstrong in the United States in ...

Edwin Howard Armstrong, bald, blue-eyed, well-heeled professor of electrical engineering at Columbia University, has made a tidy fortune for himself by inventing the super-regenerative and ...

AM and FM radio before 1920 -- Congestion and frequency-modulation research, 1913-1933 -- RCA, Armstrong, and the acceleration of FM research, 1926-1933 -- The serendipitous discovery of staticless ...