Aloha to all who have made comments.
And thanks to each of you who suggested a fix to these
problems: ground loops, loose circuit boards, rf, etc.
Ok, so now I have changed power supplies for the Pegasus.
Putting a TT PS 962 in place of the 961. (Have been using
the 961 as it seems to run cooler than the 962; 962 has
been on the Corsair II).
Also shortened the ground strap between the PS and the Peg;
about 12" now. Air space between the 962 and Peg: about 6".
No change: Peg rcvd/xmit audio is still very distorted (on the
upper bands only! see on below). Did a thorough
check of the ground strap and to the outdoor ground -- all quite
short and into damp ground; rains here daily.
However, the CW sidetone from the Peg external speaker
is just fine; either on CW xmit, regular or split, and the
"tune up" side tone is also just fine. That would seem to indicate
that the distortion is at least not in whatever the audio chain
is between the sidetone generator and the speaker.
Have just now made another discovery, after having written
all of the above. The xmit audio is a mess ONLY on the upper
bands: 20, 17, 15, 12 and 10 meters. However, on 160, 80 and
40 meters the transmit audio (as monitored on the Corsair with
the Pegasus output into a dummy load), is clean, in either
standard lower, or upper sideband. Checked xmit SSB audio
on each of the upper bands, both USB and LSB; very made
distortion. So, decided to check the xmit CW of each band.
Much to my surprise, the CW is fine on 160, 80, 40, and 30 but
only noise seems to be put out by the Pegasus when asking
for CW on any of the upper bands!! However, the CW sidetone
from the Peg external speaker is just fine on these upper bands,
just the xmit CW is lousy as only noise seems to be sent.
Thus it seems my problem is band dependant. That is why, on
the Hawaii Afternoon SSB net on 40 meters I have been told
regularly that all is well. But when on the upper bands, no one
responds to me!! I have been fooled into thinking all was
well because of the 40 meter audio. All is not well in the
Pegasus.
Guess it is back to Sevierville.
73, Jim KH7M
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