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4. Grid tubes
The triode concept – the prototype of the grid tube – is an old one. It was in January 1907 that Lee de Forest, an independent American researcher, took out the first patent. He named his device Audion, at a time when the amplification of sound signals for telephony was mobilizing the industry. The patent was assigned to AT & T (Western Electric) in 1920, who shared the rights with GE (RCA) for the development of the TSF and telephone, and de Forest reinvested his fortune ($400,000) to develop (with mixed success as far as he was concerned) talking pictures ...
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Grid tubes
Bibliography
Events
The proceedings issue of the IVEC (International Vacuum Electronics Conference, an annual event sponsored by the IEEE) is the essential publication for keeping abreast of developments in electronic tube technologies and their applications.
Statistical and economic data
The list of players is as complete as possible, but inevitably contains a few omissions, which the author hopes will not be held against him. Size differences between these players are not indicated, as they can be significant.
The industrial players (table 1...
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