>>I read that Carl suggested removing mods to go "original",
>>but following the input circuit changes per Rich's suggestions
>>to reduce VSWR (reducing coil windings and changing in/out caps)
>>is pretty hard to undo.
>
>indeed, Jon, and for what?. . The idea that input SWR could be
>significantly related to intermittent Tune-C arcing is not reasonable.
>One of the nagging problems with parasites is that they are seemingly
>female, and thusly can change their minds at any time.
> . As Murphy said: Some things are more complicated than they look.
Well, first of all, I wasn't sure which input changes Bennet had
originally done. Yes, you are correct, decreasing input VSWR should not
correspond to the arcing. What my thought was (and I am grasping for
something here) is that if something is miswired or hooked in
incorrectly, there could *possibly* be a problem. I am trying to follow
what I would do in this case. To paraphrase Sherlock Holmes, "When all
reasonable explanations have failed, the one of the remaining
possibilities is the answer however unlikely." It went something like
that! So I am just trying to eliminate all possible sources of problem
however unlikely they may be.
I was under the impression that some of the mods he did on the input side
might have been adding nichrome suppressors to the grid leads like you
suggest. If one put too much inductance in that part of the circuit, one
could cause potential instability. Same thing goes if there is not
enough inductance (which is why you suggest adding some). Instability is
not caused ONLY by the output circuitry.
Anyhow, the question of wether or not his arcing is due to parasitics is
still not settled in my mind. That's why I suggested he go over with a
fine tooth comb all of the mods he had done and look for errors.
73,
Jon
KE9NA
--------------------------------------------------------------------------
Jon Ogden
jono@enteract.com
www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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