Kathy,
The bottom section of this page may provide some ideas:
http://www.w8ji.com/loading_amplifier.htm
Since you've looked at some other possibilities in the
air variables I'm going to guess a padding capacitor may have
drifted in value or failed but is not showing any visible signs
of that failure.
Just a wild guess ...
David KD4E
> About 6 weeks ago I wrote about some problems I was having
> resurrecting a Hunter 2000C. Colin Lamb came through with the
> shorting switch I needed, thanks again Colin. The question of what
> the meters were ended up being solved, It was a 1ma for plate voltage
> and current, and a 200mma for watt meter for anyone's future
> reference. Everything is back up and running fine, but for one last
> problem. As I tune up, I'm getting some arcing in the tuning
> capacitor at times. I've visually inspected it as best I can and
> can't see any problems, like bent parts or and differences in the
> spacing between plates. Obviously I don't want this to continue
> before I cause pitting to occur. I'm wondering if there is still HV
> insulation spray available. I remember years ago having a spray can
> of a red insulation that I used on some big filter caps that were
> arching down the ceramic posts and it stopped the problem. Or should
> I look for some thin Teflon sheets that could be inserted somehow
> between plates to add that needed protection? Anyone have any ideas
> what I can do to stop this? Both loading and tuning use E F Johnson
> type 154-40 variables, but the problem is happening with the tuning
> one, not the loading one. 73, Kathy PS It isn't a swr problem as it
> has happened even with my Cantenna dummy load.
--
*David* KD4E
ARES-EC Bulloch County, Nevils, Georgia USA
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