[Boatanchors] tube sub's

Fri, 01 Nov 2002 10:47:54 -0700

P.S... using a 5963 or a 12AU7A etc. tube as the first tube in a series
filament string will cause all the tubes to 'warm-up' more slowly than
'normal' , but it also provides a good measure of current control for the
string... if used in an oscillator string , it will make the oscillator
more stable than if the "A" tubes were not used, but it owuld take a
minute or so longer to heat to operating temperature.... Hence the use of
a 12BH7A etc in place of a Ballast tube in the 390/390A... 73 de Jordan...

[email protected] wrote:

> I recently destroyed 7 perfectly good 12AU7 tubes by applying a
> different filament voltage by mistake.  lesson learned.  I got a bunch
> of 5963 tubes which are listed as a replacement for them.  Would there
> have been a reason to list 6 of the tubes in this piece of gear as
> 12AU7's and one 5963?  Any reason i can't use the 5963's in place of
> them?  Filament E and I is same.
>
> At the price of 12AU7's, and the 5963's are free it makes it a heck of
> lot cheaper to use them.  Just wondering if there is something you
> knowledgeable folks might have hidden in the back of the momory about
> this.
>
> Larry
> W0OGH
> _______________________________________________
> Boatanchors mailing list
> [email protected]
> http://mailman.qth.net/mailman/listinfo/boatanchors