Re: new tubes

To: tesla-at-pupman-dot-com
Subject: Re: new tubes
From: Ed Phillips <evp-at-pacbell-dot-net> (by way of "Terry Fritz (moderator)" <twf-at-verinet-dot-com>)
Date: Sat, 05 Dec 1998 07:27:30 -0700
Approved: twf-at-verinet-dot-com

Tesla List wrote:
> 
> Original Poster: "D.C. Cox" <DR.RESONANCE-at-next-wave-dot-net>
> 
> to: Ben
> 
> One reason tubes run red hot plates is due to parasitic oscillations ---
> very high freq oscillations that don't help the fundamental at all.  The
> older tube editions of ARRL's Radio Amateur's Handbook have some good
> articles on dealing with these problems.  Also, be sure to run fil.aiment
> chokes as well.  Many tube experimenters ignore these two areas and their
> plates do run hotter than they should.
> 
> DR.RESONANCE-at-next-wave-dot-net
> 

	Most power tubes run with the plates showing at least some color at
rated dissipation.  Many "radiation-cooled" tubes such as the 100T or
the 304TH/TL's ran bright orange.  As long as the tube materials will
withstand the temperature (Tantalum and Tungsten certainly do), and as
long as the tube is properly outgassed (as these were) all is well and
the life is good.

Ed