Re: TOM VALES

To: tesla-at-pupman-dot-com
Subject: Re: TOM VALES
From: Ed Phillips <evp-at-pacbell-dot-net> (by way of Terry Fritz <twf-at-verinet-dot-com>)
Date: Tue, 06 Apr 1999 11:41:48 -0600
Approved: twf-at-verinet-dot-com

Tesla List wrote:
> 
> Original Poster: "B**2" <bensonbd-at-erols-dot-com>
> 
> Hi All,
>     Tom Vales, a member of the list and the TCBA, helped with the
> following very fine article:
> 
> HOW EWEN AND PURCELL DISCOVERED THE 21 cm INTERSTELLAR HYDROGEN LINE
> BY Karl D. Stephan
> in IEEE Antennas and Propagation, Volume 41, No. 1, February 1999,
> pages 7 to 16
> 
>     There is a picture of the 3C22 "lighthouse" tube.  Would this work
> for a HFTTC?

        The 3C22 is a very fragile tube, both mechanically (seals break very
easily) and electrically (tendency to gas when over heated).  Also, it
is not a very high power tube.  Any of the big coventional triodes would
be a better and more satisfying choice.  Besides, as far as I know, the
3C22 hasn't been made since WW2 and any still lying around are suspect. 
I have several NIB 3C22's here, but the only one I've tried to fire up
turned out to be gassy.  If you want to use a disk-seal tube, which I
don't recommend because of the cost, a 4X250A or equivalent would be a
much better choice, but not as good as any of the "big old transmitting
triodes".

Ed