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Cunningham Tubular Audio Tron
Before 1915 Deforest had a monopoly in vacuum tubes. The only way to obtain a Deforest Audion was to buy a complete detector. Even replacement tubes only could be had when the defective tube was exchanged. In 1915 when E. T. Cunningham started producing the Audio Tron, this all changed. The Audio Tron was an excellent tube in its day and had none of the restrictions or complications that Deforest had placed on his tubes to that point. Cunningham Audio Trons were a success. To counter Cunningham’s success, Deforest introduced the Tubular Audion in 1916.

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Copyright 2003-2004 Howard Stone PhD.
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