[Elecraft] k2 output power regulation goes haywire

[hb9dum]

Hi,
I finished my K2, everything worked fine, everything was to specs and I did=
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all the alignments and it seemed ok. Somedays later I added the SSB option,=
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and then the noise blanker. That's when the problems started. The output=20
power became uncontrollable and started to oscillate between 0.1 and 15 W,=
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occasionally there was no power at all for a while. This behavior is=20
independent of the power I ask for. I removed both of the options but the=20
problem persisted. I checked voltages, and indeed the voltages on q24 seem =
to=20
be too high. Even more weird, after a while things got back to normal, only=
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to reappear a while later.
This problem has already been described on the list. But all of the things=
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evoked in these threads check out ok for me (inspection for unsoldered=20
components etc). The weirdest phenomenon: I can stabilize the circuit by=20
"tapping" on the enclosure. So it seems to be something mechanical, but I=20
cannot find anything, not even with a magnifying glass. Any ideas?
=2D-=20
vy 73 de hb9dum J=FCrgen
loc: jn36hm