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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.
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.
The history of amateur radio, dates from the dawn of radio communications, with published instructions for building simple wireless sets appearing at the beginning of the twentieth century. [1] Throughout its history, amateur radio enthusiasts have made significant contributions to science , engineering , industry , and social services .
Guglielmo Giovanni Maria Marconi [11] [12] was born in Palazzo Marescalchi in Bologna on 25 April 1874, the second son of Giuseppe Marconi (an Italian aristocratic landowner from Porretta Terme who lived in the countryside of Pontecchio) and his Irish wife Annie Jameson (daughter of Andrew Jameson of Daphne Castle in County Wexford, sister of Scottish naturalist James Sligo Jameson, and ...
Armstrong has been called "the most prolific and influential inventor in radio history". [61] The superheterodyne process is still extensively used by radio equipment. Eighty years after its invention, FM technology has started to be supplemented, and in some cases replaced, by more efficient digital technologies.
The cost of gas was just $1.12 — less than half of today's prices. Today, a gallon of milk will set you back $3.52, but in 1985, you could pick up that same gallon for $2.26.
In the late 1980s or early 1990s, [10] [11] [12] Baylis saw a television programme about the spread of AIDS in Africa and realised that a way to halt the spread of the disease would be to educate and disseminate information by radio. [11] [13] Within 30 minutes, he had assembled the first prototype of his most well-known invention, the wind-up ...