Jim Spears" said:
>
> >
> >> my amp supply lk-500 zb did a funny thing a while back when I powered
> >> it up after a long time in the closet and a cross country move. so
> >> far I have found a blown 1 ohm, 5 watt wire wound resistor. it was in
> >> two pieces so there is little debate on whether or not it blew...
I am one of the least experienced amplifier debuggers on the reflector having
only debugged and repaired five HF amplifiers (some more than once due to
severe contest quest-op abuse). I have spent a great deal of time however
troubleshooting other electronic things in my career.
I try to start with an open mind to the problem. Root cause determination is a
methodical process. Analyze the failure and then take the simplest and least
expensive steps first working toward the more expensive and exotic. In this
case DC check the tubes, look for obvious arcing or a discharge path, inspect
and measure critical components in the path. Then replace the resistor and try
again! Dust, bugs, errant shards of solder, etc. could surely trigger the
disappearing glitch resistor trick. Doesn't it make sense after following the
steps above to just replace the resistor and fire the rig up again? Then take
the next step.
I stand ready to be corrected!
--
73 es God Bless de KK1L...ron (kk1l@arrl.net) <><
QTH: Jericho, Vermont
My page: http://www.qsl.net/kk1l
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