[Central-Electronics] 10B Mod

[Jim Candela]

----- Original Message ----- 
From: "k7fm" <k7fm at teleport.com>

>I think the early CE exciters used a 12AU7 for the 9 mc (it was still mc in 
>those days) oscillator.  That was replaced by a 6U8, and stability of the 
>crystal oscillator was improved.  There was an article in CQ on stabilizing 
>the early 12AU7 crystal oscillator.
>
> 73,  Colin  K7FM

   Thanks Colin. With my 20a with an X-Locked Lake Shore "band Hopper" VFO, 
the largest source of drift is that 9 Mhz 6U8 crystal oscillator. Some of 
those original crystals shift around hundreds of HZ while the rig warms up. 
I suppose the 12AU7 version would be more drifty with the same crystal?

    I located my info on the W2EWL special, scanned it, and uploaded it. 
Here is the entire QST article:

http://pages.prodigy.net/jcandela/W2EWL/W2EWL_Special.PDF

    So what came first, the 10a commercial rig, or Tony Vitale's homebrew 
rig as posted in the QST article?

Regards,
Jim
WD5JKO