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Re: [Amps] Filament life

To: r@somis.org
Subject: Re: [Amps] Filament life
From: "S. J. Blackwell" <w5lu@hotmail.com>
Date: Sun, 16 Jul 2006 11:50:13 -0500
List-post: <mailto:amps@contesting.com>
  To prevent future semantic heartburn, should I have any further 
communications, I will use terms directly and indirectly heated cathodes, 
you can apply the thorium or barium etc as you wish.

>The tubes used in an Alpha 89 do not have filaments, they have
>heaters.  Only tubes that have thoriated tungsten filaments have
>inrush current concerns.

  I do not recall the value and do not wish to take the trouble to look it 
up, but the R is less than 1 Ohm. Please note "to some extent" below since 
we are heavily into semantics.

> > By the way, just to keep on topic, the Alpha has a low value
> > resistance in series with the filament that would limit the initial
> > cold current to some extent. Oh yes, I am aware of surge, no surge
> > thoughts re indirecly heated cathodes.
>
>What is the resistance in ohms, Sam?
>
>end,4:55am, 7/16/06
>
> > 73,
> > Sam W5LU
> >>
>R L MEASURES, AG6K. 805-386-3734
>r@somis.org
>
73,
Sam,W5LU


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