[BC] DeForest and pure vacuum, nothing about Kahn

[John Lyles]

There was certainly a rivalry between DeForest and Armstrong, as Armstrong was making much more workable receivers using Audions than DeForest had envisioned. However, I have read that it was not Armstrong who proved the merit of good vacuum but was the strong engineering group at General Electric with William Coolidge, William Comings White, Saul Dushman and Irving Langmuir. Their success led to high vacuum tubes called Kenotrons (rectifiers) and Pliotrons (oscillators). Once the techniques of hard vacuum production were mastered, the instabilities and lack of uniformity of tubes were reduced greatly, along with the colorful glow of the earlier tubes. Gain improved, as did lower noise. LDF apparently didn't understand the nature of thermionic conduction in vacuum very well. 

John Lyles

> Message: 4
> From: rj carpenter <rcarpen at comcast.net>
> Content-Type: text/plain; charset="iso-8859-1"
> 
> 
> Wasn't there a story that DeForest thought that triodes needed a little gas in them to operate.
> 
> The never, never bashful Armstrong, then an undergraduate, proved that a pure vacuum was better. DeForest didn't like this, coming from a young upstart.
> 
> bob carpenter
>