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Before the discovery of electromagnetic waves and the development of radio communication, there were many wireless telegraph systems proposed and tested. [4] In April 1872 William Henry Ward received U.S. patent 126,356 for a wireless telegraphy system where he theorized that convection currents in the atmosphere could carry signals like a telegraph wire. [5]
The early history of radio is the history of technology that produces and uses radio instruments that use radio waves. Within the timeline of radio, many people contributed theory and inventions in what became radio. Radio development began as "wireless telegraphy". Later radio history increasingly involves matters of broadcasting.
The timeline of radio lists within the history of radio, the technology and events that produced instruments that use radio waves and activities that people undertook. Later, the history is dominated by programming and contents, which is closer to general history .
21 July 1923, from 1930 part of Dutch Public Radio AM 279 kHz, 1927 also 1004 kHz, today FM network 500 W, 1927 5 kW 2RN (Irish Free State radio) RTÉ (Irish national radio & television) [40] General Post Office (O'Connell Street), Dublin, Ireland 1 January 1926 AM 380 kHz, and from Cork AM612 kHz, NDO, 50% time KRO, 50% NCRV NPO
Milestones in radio: the first half century (1895–1945). The UNESCO courier (February 1997), p. 16–21; Radio Review/Radio Listeners Guide (1925–1929), Broadcasting Yearbook (1935–2010), World Radio TV Handbook (1947–) Berg, Jerome S. The early shortwave stations: a broadcasting history through 1945 (2013) radioheritage.net
Type 'C' Form 'A' twin detector crystal radio set, manufactured by British Thomson Houston Ltd. in 1924, kept at the Museum of the radio - Monteceneri (Switzerland) Early radio telegraphy used spark gap and arc transmitters as well as high-frequency alternators running at radio frequencies. The coherer was the first means of detecting a radio ...
Radio is the technology of communicating using radio waves. [1] [2] [3] Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates oscillating electrical energy, often characterized as a wave.
Chrysler and Philco announced an all-transistor car radio in the April 28, 1955, edition of the Wall Street Journal. [1] This Philco car radio model was the first tubeless auto set in history to be developed and produced. [2] It was a $150 option for 1956 Chrysler and Imperial cars and hit the showroom floor on October 21, 1955. [3] [4] [5]