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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 earliest radio programs of the 1920s were largely unsponsored; radio stations were a service designed to sell radio receivers. In early 1922, American Telephone & Telegraph Company (AT&T) announced the beginning of advertisement-supported broadcasting on its owned stations, and plans for the development of the first radio network using its ...
1920s: Radio was first used to transmit pictures visible as television. 1926: Official Egyptian decree to regulate radio transmission stations and radio receivers. [40] Early 1930s: Single sideband (SSB) and frequency modulation (FM) were invented by amateur radio operators. By 1940, they were established commercial modes.
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 word radio is derived from the Latin word radius, meaning "spoke of a wheel, beam of light, ray".It was first applied to communications in 1881 when, at the suggestion of French scientist Ernest Mercadier [], Alexander Graham Bell adopted radiophone (meaning "radiated sound") as an alternate name for his photophone optical transmission system.
Radio broadcasting has been used in the United States since the early 1920s to distribute news and entertainment to a national audience. In 1923, 1 percent of U.S. households owned at least one radio receiver, while a majority did by 1931 and 75 percent did by 1937.
Thirty-five years ago, users heard the infamous dial-up sound for the first time. The '80s were a decade defined by major technological innovations, big hair, cult-classic movies and the start of ...
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