Invention of the Telephone    original voice .    In 1831 , Englishman Michael Faraday ( 1791 - 1867 ) proved that vibrations of metal could be converted to electrical impulses .    This was the technological basis of the telephone , but no one actually used this system to transmit sound until 1861 .    In that year , Johann Philip Reis ( 1834 - 1874 ) in Germany is said to have built a simple apparatus that changed sound to electricity and back again to sound .    A crude device , it was incapable of transmitting most frequencies , and it was never fully developed .    A practical telephone was actually invented independently by two men working in the United States , Elisha Gray ( 1835 - 1910 ) and Scottish - born Alexander Graham Bell ( 1847 - 1922 ) .    Incredibly , both men filed for a patent on their designs at the New York patent office on February 14 , 1876 , with Bell beating Gray by only two hours !    Although Gray had built the first steel diaphram / clectromagnet receiver in 1874 , he wasn t able to master the design of a workable transmitter until after Bell had .    Bell
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Publicaciones    good idea to sketch in briefly the great milestones in the history of communications .    At the beginning of our history we human beings communicated using signals and gestures accompanied by sounds .    Later we communicated through spoken language .    Then we needed to communicate across distances beyond the reach of voice .    Thus emerged smoke signals , flashing mirrors , flags , drums , etc .    By 1830 we had began to communicate at a distance by telegraph and Morse code ( 1820 ) .    In 1876 the Scot , A . Graham Bell , invented the telephone , which enabled us to communicate verbally at a distance .    In 1894 the young Italian G . Marconi invented the radio and 1901 saw the first trans - Atlantic communication by radio , although the first radio station in America did not start broadcasting until 1920 .    Teletype ( 1910 ) enabled written messages to be sent over distance using certain codes and 1923 ( Vladimir Zworykin ) saw the arrival of television which began its first regular broadcasts in 1935 .    The analogue computer dates from 1930
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