Re: VTTC Operation and Filament Warm-up

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "David Speck by way of Terry Fritz <teslalist-at-qwest-dot-net>" <dave-at-davidspeckmd-dot-org>

Ray,

My high school physics teacher (with whom I did a lot of Tesla projects 
about 35 years ago) previously worked for Sylvania, making picture tubes.

He said that applying HV before the filaments were fully warmed up would 
tend to strip the emissive coating from the filaments, causing internal 
shorts in the tube and limiting the life of the tube.  I agree that 833 
filaments, being direct heated, would not require a very long preheating 
time.  OTOH, some tubes, like my CX1159 thyratron, specify a 10 minute 
warm-up before operation.

HTH,
Dave

Tesla list wrote:

>Original poster: "Ray von Postel by way of Terry Fritz 
><teslalist-at-qwest-dot-net>" <vonpostel-at-prodigy-dot-net>
>
> >  Is it necessary to allow adequate time
> > for the filament to warm up before powering up the rest of the hv circuit?
> > Thanks