Hell gents.
As the subject line indicates, I've got a little problem with my Kenwood
TL-922A.
The background is that this amp has been in storage for a long time, almost
a decade. We have moved a few times since then and the tubes were out
of the amp in their own foam-lined boxes. The tubes were re-installed when
we moved
here about six years ago.
I decided to bring the amp out of the closet and see if it still works.
I have read here about soft-starting with a variac, but not having one,
I plugged it into 240 vac and hit the switch. The fuses blew, and there
was a faint burning smell, you know what I mean...
I took the top and bottom covers off, and seeing no apparent damage, decided
to try again. This time I put the inside covers on the HV and RF
compartments
and triggered the HV with the inside safety switch. With power on and HV
off,
the filaments lit on both tubes. With HV triggered, there was an arc in the
RF
compartment. In the process of locating the arc, I blew up a small resistor
attached
across an RF choke on one of the pins at the bottom of one of the tubes.
I had also noted the grid current pinned the meter, but this occurred
during
the first attempt. I did not see a pin number on the socket, but the
choke/resistor
assembly appear to connect directly to ground.
So... Now I know where the arc was, but don't know what caused it. I'm
looking
for advice. Is the amp worth repairing? I assume it is, although probably
not
by me. The second question would be where to repair it and what would the
cost be?
This amp is fairly low hours and in good shape otherwise.. HI!
I'm guessing a problem with the one tube, and wondering if I re-tubed would
I simply
be setting myself up for another bang? Replacing the resistor is simple
enough,
but I'm wondering if my tubes are bad due to the long period of non-use?
IN any event how could I tell?
Any help appreciated.
Thanks
Gary McAdams
WG7X
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