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the human voice or music. Alexander Graham Bell developed a machine that could
carry the human voice over wires and patented it in 1876.
Telephone
The telephone provided many features that the telegraph did not. The human
voice could be transmitted without any coding, and anyone could use the phone.
Although phones needed to be linked by wire, telephones could be linked to a cent-
ral switching station; soon it was possible to link stations, and the telephone infra-
structure was created, and people in distant cities could be linked.
Telephone use grew quickly, and Bell's Telephone Company was eventually su-
perseded by the American Telephone and Telegraph Company (AT&T) in 1885.
AT&T has done quite well since, updating technologies as they became available.
Now AT&T and other companies provide one-stop “bundled” services for cell
phones, landlines, and Internet connection.
Radio
Michael Faraday, James Clerk Maxwell, and Heinrich Hertz were scientists
whose experiments with electromagnetic waves led to Guglielmo Marconi's inven-
tion of a radio that could transmit across the English Channel. In 1901 Marconi
conducted an experiment that transmitted a signal from Cornwall, England, to
Newfoundland, a distance of 2217 miles. By 1904 radio was installed in 124 ships
at sea. Although radio waves were used, the signals in these early days were sent
in code; it was wireless telegraphy, with the same limitations as the telegraph, re-
quiring senders and receivers who knew the code.
David Sarnoff, a Marconi engineer, saw the commercial possibilities for radio
transmitting voice and music. In 1918 Marconi's company and General Electric
agreed to a merger, forming Radio Corporation of America (RCA), with Sarnoff as
the head of the company. The first commercial broadcast was by Westinghouse
Electric Company in 1920, carrying news of the U.S. presidential election. Within
a decade, radios and radio programming spread throughout the United States and
became a communication vehicle for news and entertainment unmatched until the
invention of television.
Television
Concurrently with the development of radio, the technology for television was
evolving. In 1929 the British Broadcasting Corporation began broadcasting, and in
1939 the National Broadcasting Company, part of RCA, transmitted the first tele-
vision transmission, reporting the opening of the 1939 World's Fair in New York
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