[Amps] Tube heaters

k7fm k7fm at teleport.com
Thu May 5 21:44:08 PDT 2011


I found this article about a 958 acorn tube:

" In 1942 the 958 received tighter controls on emission and became the 958A. 
This was in response to a report from the Navy that, in one of their 
transmitters -- possibly an early model of the TBY -- the tube kept 
oscillating even after filament power was turned off. Filaments with 
unusually high emission could keep going, heated only by the plate current."

The 958 tube is similar to the lovable old 955, although it is a transmitter 
version (more filament power).  But, the comment raises an interesting 
point.  This is sort of like a vacuum tube that "diesels" afyou remove 
filament power.  With tube plates thare are red or white hot, did any of the 
tubes ever take advantage of this characteristic?

73,  Colin  K7FM 



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