Hello-I am a newly-joined member of your group but have been on 160 for
awhile. Until this past summer, I ran barefoot but the urge to raise my
country total above 100 prompted me to purchase an amp.
The Clipperton L works well on all bands but 160. It looks as if someone in
the past had problemns and rewound the tank coil with #14 stranded(!!)
covered wire. As soon as I fired it up I realized there were problems.
Power output starts out at about 500 watts and after a few dits and dahs it
drops slowly to about 375-400 watts. IT DOES THIS ONLY ON 160. So, I
re-wound the coils using #14 Formvar-coated wire. The only change is that
for the same plate current as before, power output begins at 600+ watts and
drops.
Obviously, something is heating up, as a slight constant re-tuning of the
plate cap restores power output.
Could it be the coil? By the time I get the cover off everything has cooled
down!
Could it be one of the doorknob caps slung across the plate cap (2x200
pf@5kv on the plate which is 250 mmfd)? Perhaps one of the doorknobs across
the loading cap?
Anybody had a similar problem?
There are no visible or audible signs of anything wrong-no arcing, no
discoloration.
I sure would appreciate suggestions.
Thanks, 73 and Seasons Greetings to all.
Bill, VE3CSK
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