[Amps] Thoriated tungsten lifetime when idling tspa

[Tom W8JI]

> Also I know I have seen documentation at some time years 
> ago which
> cautioned against this type of operation but I cannot 
> remember the
> context or the tubes involved. I am pretty sure it was 
> thoriated
> tungsten types but after all this time, I can't be 
> positive. If I run
> across the info, I'll be sure to post it here.


Interesting, because when we would get a low emission batch 
of 3CX1200's they would have us run the tubes for days 
without any anode voltage or current at extra filament 
voltage.

It would always bring the emission up, but once in a while 
it would not "stick".