Lee De Forest

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Lee De Forest - Wikipedia, the free encyclopedia
Lee De Forest, (August 26, 1873 - June 30, 1961) was an American inventor ... Lee De Forest at National Inventors ... Greene's Who said Lee de Forest was the "Father of ...
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Lee de Forest, American Inventor
Lee de Forest, 1873-1961, was a Yale University Ph.D, who in 1906 invented the first vacuum tube known as the Audion. ...
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De Forest
Lee de Forest was one of the most important of the inventors of radio and electronic ... Lee de Forest's father hoped that his son would follow in his footsteps. ...
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Lee De Forest
describes history of most important invention of the 20th century: the transistor. ... Lee De Forest. 1873-1961. Lee De Forest invented the audion, a vacuum tube device that ...
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Meet Lee de Forest
Lee de Forest, born 1873 in Iowa, died 1961 in Los ... Dr. Lee de Forest was an inventor who changed the world with ... Lee de Forest was born in Council Bluffs, Iowa in ...
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De Forest, Lee: Biography from Answers.com
Lee De Forest American physicist and inventor (1873-1961) De Forest, who was born in Council Bluffs, Iowa, was interested in science from the age of
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Lee de Forest
Born in Iowa, Lee de Forest's father became the President of Alabama's black Talledega ... July 13 2006: Lee de Forest was shipped without a GPS unit to Julie ...
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A Science Odyssey: People and Discoveries: Lee de Forest
Lee de Forest. 1873 - 1961. Lee de Forest's father was a minister and hoped that his son would follow in his ... De Forest sued, with legal action lasting until 1934. ...
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{{Infobox Celebrity| name = Lee De Forest| image = Lee De Forest.jpg| caption = De Forest patented the Audion tube,
a triode.| birth_date = | birth_place = Council Bluffs, Iowa| occupation = [Inventor, [1873 – June 30, 1961) was an United States inventor with over 300 patents to his credit. De Forest invented the Audion tube, a vacuum tube that takes relatively weak electrical signals and amplifies them. De Forest is one of the fathers of the "electronic age", as the Audion helped to usher in the widespread use of electronics.

He was involved in several patent lawsuits and he spent a fortune from his inventions on the legal bills. He had four marriages and several failed companies, he was defrauded by business partners, and he was once indicted for mail fraud, but was later acquitted.

He was a charter member of the Institute of Radio Engineers, one of the two predecessors of the IEEE (the other was the American Institute of Electrical Engineers).

Birth and education Lee De Forest was born in 1873 in Council Bluffs, Iowa to Henry Swift DeForest and Anna Robbins. Media:1900 census DeForest.jpg 1900 US Census in Milwaukee, Wisconsin Media:1920 census DeForest.jpg 1920 US Census in the Bronx, New York

His father was a Congregational church minister who hoped that his son would become a minister also. He accepted the position of President of Talladega College, a traditionally African American school, in Talladega, Alabama where Lee spent most of his youth. Most citizens of the white community resented his father's efforts to educate black students. Lee De Forest had several friends among the African American children of the town.

De Forest went to Mount Hermon School, and then he enrolled at the Sheffield Scientific School at Yale University in 1893. As an inquisitive inventor, he tapped into the electrical system at Yale one evening and completely blacked out the campus, leading to his suspension. However, he was eventually allowed to complete his studies. He paid some of his tuition with income from mechanical and gaming inventions, and he received his Bachelor's degree in 1896. He remained at Yale for graduate studies, and earned his Doctor of Philosophy in 1899 with a doctoral dissertation on radio waves.

Audion De Forest's interest in wireless telegraphy led to his invention of the Audion tube in 1906, and he developed an improved wireless telegraph receiver. At that time, he was a member of the faculty at the Armour Institute of Technology, now part of the Illinois Institute of Technology. He filed a patent for a two-electrode device for detecting electromagnetic waves, a variant of the Fleming valve invented two years earlier. His Audion tube, a three-electrode device (plate, cathode, control grid), was a vacuum tube which allowed for amplification for radio reception.

In 1904, a De Forest transmitter and receiver were set up aboard the steamboat Haimun operated on behalf of The Times, the first of its kind. The De Forest Wireless Telegraphy Tower: Bulletin No. 1, Summer 1904.

De Forest did not however understand how his invention worked, and others had to explain it to him. The American inventor Edwin Armstrong was the first to explain the correct operation of this device, and also to improve it to the point where it could actually provide useful amplification. De Forest claimed that the operation was based on ions created within the gas in the tube, and warned others from removing this by creating a vacuum. His own prototypes never achieved amplification.

Marriages Lee de Forest had four wives:

Middle years De Forest invented the Audion tube in 1906, an improved version of John Ambrose Fleming's recently invented diode vacuum tube detector (radio). In January 1907, he filed a patent for a three-electrode version of the Audion, which was granted US Patent 879,532 in February 1908. It was also called the De Forest valve, and since 1919 has been known as the triode.

De Forest's innovation was the insertion of a third electrode, the grid, in between the cathode (filament) and the anode (plate) of the previously invented diode. The resulting triode or three-electrode vacuum tube could be used as an amplifier for electrical signals, and, equally important, as a fast (for its time) electronic switching element, later applicable in digital electronics (such as computers). The triode was vital in the development of long-distance (e.g. transcontinental) telephone communications, radio, and radars. The triode was an important innovation in electronics in the first half of the 20th century, between Nikola Tesla's and Guglielmo Marconi's progress in radio in the 1890s, and the 1948 invention of the transistor.

De Forest came to San Francisco in 1910, and worked for the Federal Telegraph Company, which began developing the first global radio communications system in 1912.

The United States Attorney General sued De Forest for fraud (in 1913) on behalf of his shareholders, stating that his claim of regeneration was an "absurd" promise (he was later acquitted). Nearly bankrupt with legal bills, De Forest sold his triode vacuum-tube patent to American Telephone and Telegraph in 1913 for the bargain price of $50,000.

De Forest filed another patent in 1916 that became the cause of a contentious lawsuit with the prolific inventor Edwin Howard Armstrong, whose patent for the regenerative circuit had been issued in 1914. The lawsuit lasted twelve years, winding its way through the appeals process and ending up before the Supreme Court of the United States in 1926. The Supreme Court ruled in favor of De Forest, although the view of many historians is that the judgment was incorrect.

Radio pioneer In 1916, De Forest, from 2XG, broadcast the first radio advertisements (for his own products) and the first Presidential election report by radio in November of 1916 for Charles Evans Hughes and Woodrow Wilson. A few months later, DeForest moved his tube transmitter to High Bridge, New York.

Just like Pittsburgh’s KDKA four years later in 1920, DeForest used the Hughes/Wilson presidential election returns for his broadcast. The New York American installed a private wire and bulletins were sent out every hour. About 2000 listeners heard The Star-Spangled Banner and other anthems, songs, and hymns. DeForest went on to sponsor radio broadcasts of music, featuring opera star Enrico Caruso and many other events, but he received little financial backing.

Phonofilm sound-on-film process In 1919, De Forest filed the first patent on his sound-on-film process, which improved on the work of Finnish inventor Eric Tigerstedt, and called it the De Forest Phonofilm process. It recorded sound directly onto film as parallel lines. These lines photographically recorded electrical waveforms from a microphone, which were translated back into sound waves when the movie was projected. This system, which synchronized sound directly onto film, was used to record stage performances (such as in vaudeville), speeches, and musical acts. De Forest established his De Forest Phonofilm Corporation, but he could interest no one in Hollywood in his invention at that time.

De Forest premiered 18 short films made in Phonofilm on 15 April 1923 at the Rivoli Theater in New York City. He was forced to show his films in independent theaters such as the Rivoli, since the movie studios controlled all major theater chains. De Forest chose to film primarily vaudeville acts, not features, limiting the appeal of his process. Max Fleischer and Dave Fleischer used the Phonofilm process for their Sound Car-Tune series of cartoons -- featuring the "Follow the Bouncing Ball" gimmick -- starting in May 1924. De Forest also worked with Theodore Case, using Case's patents to perfect the Phonofilm system. However, the two men had a falling out, and Case took his patents to studio head William Fox (producer), owner of Fox Film Corporation, who then perfected the Fox Movietone process. Shortly before the Phonofilm Company filed for bankruptcy in September 1926, Hollywood introduced a different method for the "talkies", the sound-on-disc process used by Warner Brothers as Vitaphone.

Eventually Hollywood came back to the sound-on-film methods De Forest had originally proposed, such as Fox Movietone and RCA Photophone. A theater chain owner, M. B. Schlesinger, acquired the United Kingdom rights to Phonofilm and released short films of British music hall performers from September 1926 to May 1929. Almost 200 short films were made in the Phonofilm process, and many are preserved in the collections of the Library of Congress and the British Film Institute. Today, many sources such as the Encyclopaedia Britannica list De Forest as one of the inventors of sound film.

Later years De Forest sold one of his radio manufacturing firms to RCA in 1931. In 1934, the courts sided with De Forest against Edwin Armstrong (although the technical community did not agree with the courts). De Forest won the court battle, but he lost the battle for public opinion. His peers would not take him seriously as an inventor or trust him as a colleague. For De Forest's initially rejected, but later adopted, movie soundtrack method, he was given an Academy Honorary Award (Oscar) in 1959/1960 for "his pioneering inventions which brought sound to the motion picture", and a star on the Hollywood Walk of Fame.

De Forest was the guest celebrity on the May 22, 1957 episode of the television show This Is Your Life, where he was introduced as the "Father Of Radio and the Grandfather of Television".

Death He died in Hollywood in 1961 and was interred in San Fernando Mission Cemetery in Los Angeles, California.

Legacy De Forest received the IRE IEEE Medal of Honor in 1922, as "recognition for his invention of the three-electrode amplifier and his other contributions to radio". In 1946, he received the Edison Medal of the American Institute of Electrical Engineers 'For the profound technical and social consequences of the grid-controlled vacuum tube which he had introduced'. An important annual medal awarded to engineers by the Institute of Electrical and Electronic Engineers is named the Lee De Forest Medal.

Politics De Forest was a conservative Republican and fervent anti-communist and anti-fascist. In 1932 he had voted for Franklin Roosevelt, in the midst of the Great Depression, but later came to resent him and his statist policies called him American's "first Fascist president." In 1949, he "sent letters to all members of Congress urging them to vote against socialized medicine, federally subsidized housing, and an excess profits tax." In 1952, he wrote newly elected Vice President Richard Nixon, urging him to "prosecute with renewed vigor your valiant fight to put out Communism from every branch of our government." In December 1953, he cancelled his subscription to The Nation, accusing it of being "lousy with Treason, crawling with Communism."James A. Hijya, Lee De Forest and the Fatherhood of Radio (1992), Lehigh University Press, pages 119-120

Quotes De Forest was given to expansive predictions, many of which were not borne out, but he also made many correct predictions, including microwave communication and cooking.



Trivia Lee De Forest's great nephew, actor Calvert DeForest, became well known in another broadcasting venue some 75 years following his uncle's Audion invention. Calvert DeForest portrayed the comic "Larry 'Bud' Melman" character on David Letterman's late night television programs for two decades.

References and notes External links Patents Patent images in TIFF format

Other sites



Lee de Forest, American Inventor
Lee de Forest, 1873-1961, was a Yale University Ph.D, who in 1906 invented the first vacuum tube known as the Audion. It was first used as a detector of radio waves, then as an ...

Meet Lee de Forest
Lee de Forest, born 1873 in Iowa, died 1961 in Los Angeles. He was one of the most productive and controversial inventors of the 20th Century

Lee De Forest - Wikipedia, the free encyclopedia
Lee De Forest, (August 26, 1873 – June 30, 1961) was an American inventor with over 300 patents to his credit. De Forest invented the Audion, a vacuum tube that takes relatively ...

Lee De Forest
Vinyl Record Collectors site provides stunning and comprehensable information that educate the vinyl record collectors on the secrets of the vinyl record discoveries, and Lee De ...

Lee De Forest
describes history of most important invention of the 20th century: the transistor. Also... see the television documentary hosted by Ira Flatow, airing on local PBS station fall ...

Dr. Lee De Forest - Radios & Research
Chronicles the history of De Forest radios.

Dr Lee De Forest.
Lee De Forest was born in Council Bluffs, Iowa, on August 26, 1873. His father, Henry Swift DeForest, was a Congregational minister who hoped that his son would also become a ...

Lee De Forest definition of Lee De Forest in the Free Online ...
De Forest, Lee, 1873–1961, American inventor, b. Council Bluffs, Iowa, grad. Yale, 1896. He was a pioneer in the development of wireless telegraphy, sound pictures, and ...

Lee De Forest - Space Telegraphy
Lee DeForest invented the triode amplifier and space telegraphy. ... By Mary Bellis. The prolific American inventor Lee De Forest (1873-1961) is one of several pioneers of radio ...

Lee De Forest - Hutchinson encyclopedia article about Lee De Forest
De Forest, Lee (1873-1961) US physicist and inventor who in 1906 invented the triode valve, which contributed to the development of radio, radar, and television.





 
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