"""A model, Rosalie Deneve, lying on top of a large mock-up of a radio receiver at a 1923 radio convention. Exhibit by Adams-Morgan Co.promoting their Paragon line of receivers at the 3rd Annual Convention of the 2nd Radio District, held at Hotel Pennsylvania, New York City, March 1-3, 1923. Radio broadcasting sprang up spontaneously in the US in 1920, igniting a ""radio craze"" among a Roaring 20s public fascinated by this new high-tech entertainment. The first commercial vacuum tube receivers like this one came out in 1920, made possible by a market-sharing and patent cross-licensing agreement brokered in 1919 by the US government between corporate giants Westinghouse, General Electric, AT&T, United Fruit, and RCA. Tuned radio frequency (TRF) receivers like this had multiple tuned circuits (two big knobs, center) which had to be tuned in tandem to bring in a station."" Caption:""Rosalie Deneve, of New York, listening in on the huge Paragon set at the Second Annual Convention. Date3 March 1923 Source Retrieved January 28, 2014 from Radio World, Hennessey Radio Publications Corp., New York, Vol. 2, No. 25, March 17, 1923, p. 16 on Google Books"
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