Biographies of Silicon Valley protagonists

A History of Silicon Valley

This biography is an appendix to my book "A History of Silicon Valley"

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Lee DeForest

Lee DeForest (Iowa, 1873) grew up in Alabama. He graduated in physics from Yale University in 1898 with a dissertation on radio waves. He then moved to Chicago where he worked for Western Electric and other companies. In 1902 he also tried to start his own company, De Forest Wireless Telegraph Company, to sell wireless telegraph devices for the Navy. In 1904 British scientist John Ambrose Fleming, who was a consultant to the Marconi Wireless Telegraph Company, invented a two-element "electronic valve" (a diode) that was capable of detecting wireless signals, such as Morse code. In 1906, while at the Armour Institute of Technology, DeForest invented a three-element version of it, the "audion" (a triode), which was not only a detector but also as an amplifier. The audion simply had a third electrode between the cathode and the anode, but the difference was enormous: it could be used to transmit sound, not just Morse signals. However, he didn't realize it at the time. In 1907 DeForest formed the DeForest Radio Telephone Company and proceeded to promote his broadcasting feats (that still employed the old technology): in july 1907 he carried out the first voice transmission from a ship and in january 1910 he broadcast from New York a live performance by legendary Italian tenor Enrico Caruso. The company, however, got into trouble. In 1910 DeForest moved to San Francisco and got into radio broadcasting in earnest, while being investigated for fraud after his company went bankrupt. FTC hired Lee DeForest at its Palo Alto laboratory and exploited the audion to become a leader in communication systems. In 1913 DeForest sold the patent for the audion to Graham Bell's AT&T in New York, and AT&T used it to set up the first coast-to-coast telephone line (january 1915), just in time for the Panama-Pacific International Exposition to be held in San Francisco. The audion was still used only for receivers, while most transmitters were arc-based. It was only in 1915 that DeForest realized that a feedback loop of audions could be used to build transmitters as well. DeForest moved to New York to found the Radio Telephone and Telegraph Company, which began to use his audion also for transmitting and not only for receiving, and in 1916 shocked the nation by broadcasting the results of the presidential elections with music and commentary from New York to stations within a range of 300 kilometers: this time he used his audion and not the Poulsen arc. In march 1920 he returned to San Francisco to set up a broadcasting station (6XC, later KYZ in Oakland). DeForest is also credited with using the term "radio" to refer to wireless transmission (in the name of his 1907 company). DeForest's audion was later used to manufacture consumer radios, radars, early television sets and early computers until the transistor finally made it obsolete. In 1919, again on the East Coast, DeForest pioneered a system to make "talking movies", and in 1922 founded the DeForest Phonofilm Company in New York. He showed the first films with sound in small alternative theaters because the big ones were controlled by Hollywood companies that did not endorse his system. When Hollywood finally began to make talking movies, different systems would be employed. During the Great Depression he sold his business to RCA and was marginalized by the establishment. He spent the rest of his life as a hardcore right-wing Republican, ranting against socialism.

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