Re: First VTTC light, and a few questions

[Parpp807-at-aol-dot-com (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Grayson,
As the circuit starts to oscillate, as the plate current increases, all sorts 
of dirty RF
flows into the filament circuit. I played with a pair of #10s and a pair of 
45s. Both tubes are directly heated and exhibited the behavior you describe. 
I have very little experience with
VTTCs. Bypassing the filaments to ground eliminated the problem. I used a TV 
transformer with a fil CT but that should not make any difference. I have 
some big
plate transformers that I hope to use with 4-811s or 4-836 triodes. The 836 
has a large graphite plate and should make things nice and toasty. Sorry I 
can't be of greater help
but my experience is :-((.

Happy day,
Ralph Zekelman