Monday, August 11, 2008

The History of Radio

Military Use and Patent Control

When the United States entered the first world war in 1917, all radio development was controlled by the U.S. Navy to prevent its possible use by enemy spies. The U.S. government took over control of all patents related to radio technology.

In 1919, after the government released its control of all patents, the Radio Corporation of America (RCA) was established with the purpose of distributing control of the radio patents that had been restricted during the war.

Radio Speaks

The first time the human voice was transmitted by radio is debateable. Claims to that distinction range from the phase, "Hello Rainey" spoken by Natan B. Stubblefield to a test partner near Murray, Kentucky, in 1892, to an experimental program of talk and music by Re Ginald A. fessenden, in 1906, which was heard by radio-equipped ships within several hundred miles.

Reginald A. Fessenden

Canadian, Reginald,Fessenden is best known for his invention of the modulation of radio waves and the fathometer. Fessenden worked as as a chemist for Thomas Edison during the 1880s and later for Westinghouse. Fessenden started his own company where he invented the modulation of radio waves, the "heterodyne principle" which allowed the reception and transmission on the same aerial without interference.

True Broadcasting Begins

In 1915, speech was first transmitted across the continent from New York City to San Francisco and across the Atlantic Ocean from Naval radio station NAA at Arlington, Virginia, to the Eiffel Tower in Paris.

On November 2, 1920, Westinghouse's KDKA-Pittsburgh broadcast the Harding-Cox election returns and began a daily schedule of radio programs.

The first ship-to-shore two way radio conversation occurred in 1922, between Deal Beach, New Jersey, and the S.S. America, 400 miles at sea. However, it was not until 1929 that high seas public radiotelephone service was inaugurated. At that time telephone contact could be made only with ships within 1,500 miles of shore. Today there is the ability to telephone nearly every large ship wherever it may be on the globe.

Commercial radiotelephony linking North America with Europe was opened in 1927, and with South America three years later. In 1935 the first telephone call was made around the world, using a combination of wire and radio circuits.

FM Radio

Edwin Howard Asmstrong invented frequency-modulated or FM radio in 1933. FM improved the audio signal of radio by controlling the noise static caused by electrical equipment and the earth's atmosphe. Until 1936, all American transatlantic telephone communication had to be routed through England. In that year, a direct radiotelephone circuit was opened to Paris. Telephone connection by radio and cable is now accessible with 187 foreign points.

Radio technology has grown significantly since its early development. In 1947, Bell Labs scientists invented the transister. In 1954, a then small Japanese company called Sony introduced the transistor radio.

FM Antenna System

In 1965, the first Master FM Antena System in the world designed to allow individual FM stations to broadcast simultaneously from one source was erected on the Empire State Building in NYC.

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