ORIGINAL MESSAGE:
On Tue, 01 Sep 2009 14:09:22 -0400, Ed Post <edpostiii@comcast.net> wrote:
>Where do I go next?
>
>Could it be an open electrolytic cap? would that blow a fuse?
REPLY:
An open filter cap would not blow a fuse.
Put everything back together and check for shorts to ground in the HV circuit.
In a working amp the resistance to ground should be high - on the order of 100 k
ohms or more. BE SURE YOU DISCHARGE THE HV TO GROUND BEFORE MAKING THIS TEST or
your ohm meter may be damaged, not to mention yourself. Electrolytic capacitors
do not discharge instantly. They retain a tiny charge, a few millivolts, for a
remarkably long time. A few millivolts is enough to affect your meter's reading.
Connect a grounding lead and leave it there for several minutes before
connecting your ohm meter. Remove the grounding lead and make your tests.
With any luck, you will show only a few ohms to ground. Start disconnecting
things one at a time until the short disappears, then measure directly across
the part you disconnected. That's your culprit.
Any old time repairman will tell you finding shorts like this is not always that
simple, but this should get you started. Let us know what you find.
73, Bill W6WRT
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