A Thumbnail History of Electronics

 

umdstrip.gif (1470 bytes)

V. Television
The pioneers of television were the Russians, Nipkow who invented a mechanical revolving scanning disk in 1884 and Rosing who used a cathode ray tube in 1907 to display images from a mechanical transmitter. In Britain in 1923, John Logie Baird began to demonstrate television transmission using Nipkow disks. In America, Rosing’s student, Vladimir Zworykin, filed a patent for an electronic television system in 1923, but the project was dropped by Westinghouse and Zworykin had to wait for RCA to restart the project in 1930. Meanwhile, an Idaho schoolboy, Philo Farnsworth, invented an electronic system in 1922, and by 1927 had transmitted television images. The development of the kinescope and its successor, the image orthicon tube, at RCA, plus a licensing agreement between RCA and Farnsworth led to the first appearance of commercial TV in April,1939 at the RCA pavilion at the New York World Fair.

baird.gif (9467 bytes)John Logie Baird (1888 -1946) graduated from the University of Glasgow and worked for a while as an engineer for a Glasgow electrical company, but was discharged when he blacked out half the city in an unauthorized experiment to create diamonds. In the 1920’s Baird began working on television using the Nipkow mechanical scanning disk. In 1926 he demonstrated the first television. He went on to demonstrate the first color and stereo televisions and succeeded in recording his video signals on disks. From 1929 to 1935, the BBC used the Baird mechanical television system; in the last part of this period it shared time with the electronic system. Mechanical systems, however, were limited to about 200 lines per frame and could not compete successfully against electronic systems.

 

farnswor.gif (8830 bytes)Philo Taylor Farnsworth (1906-1971), was a 15-year old Mormon high school student in Rigby, Idaho in 1922 when he invented an electronic television system and explained it to his chemistry teacher. In 1926, at age 19, he received some backing and formed a company to develop television. By 1927 he had obtained his first patents, obtained financing from a group of San Francisco bankers, and displayed the first electronic television image. His success was announced in 1928, the first public demonstration was given in 1934, and by 1936 his studio was broadcasting to about fifty home receivers in Philadelphia.  The next years were an odyssey of litigation as RCA tried to break the Farnsworth patents which blocked the kinescope and orthicon tubes. The Farnsworth patents were repeatedly upheld and in 1939 RCA agreed to pay royalties to the Farnsworth company.

 

zworykin.gif (8464 bytes)Vladimir Kosma Zworykin (1889-1982) was educated in Russia and France and then saw service during World War I in the Russian Army Signal Corps. After the war he emigrated to the United States and worked initially for the Westinghouse Electric Corporation where in 1923 he filed a patent application for the iconoscope, an electronic camera tube using a photo-emissive array. However, it was not until 1929 that RCA offered him the opportunity to continue working on television. Zworykin’s iconoscope led to modern televison cameras and Zworykin's kinescope was the basis for the modern television picture tube. His other inventions included a form of the electric eye and his infrared image tube led to the sniperscope and the snooperscope. He also invented a secondary-emission multiplier used in scintillation counters.

back.gif (1144 bytes) Back to "Contents"

Next next.gif (1134 bytes)