[Central-Electronics] 10A

[Robert Nickels]

On 10/19/2011 6:36 AM, Jim Candela wrote:
>     I think you answered your question, and you might have a 'dud' crystal. Also look at my post about a CB channel 4 crystal (27.005 3rd overtone) to replace the CE 9000Khz xtal.
Thanks Jim, and shame on me for not remembering that thread.   On Monday 
night I had full (5-6 watts) output using the original JK crystal, but 
then yesterday the output was low, which put me onto the notion of a 
low-output crystal, so I tried the one from my W2EWL rig, which produced 
full output.   Now today output is back up, and using my capacitive 
coupler I measure the same 9 mhz level from either crystal.  No amount 
of wiggling, tapping, or cool mist seems to change it, so I figure as 
long as I only use it on odd-numbered days I should be OK!

Comparing the 10A with the 10B was a good idea, as there aren't many 
changes but going to the pentode oscillator was one of them, so that 
would indicate this was a trouble spot.  Although the same triode 
circuit was used (copied?) in the W2EWL and a couple of other early SSB 
designs.

I'm going to watch it for a few days to see if it remains stable, then 
it's heading to join up with the 600L and Drake 1A, which ought to make 
a pretty cool station.  I did my usual AM mode audio test today on a 
dummy load by playing music thru it, and it sure makes nice-sounding AM too.

73, Bob W9RAN