Hello All,
After building almost every option that will fit into the K2 and having
everything working great the first time, I finished the KPA100 over the weekend
(after getting beyond the in-line fuse problem), and in the process, broke
something in the K2.
The KPA100 checked out fine but when I installed it in the K2, nothing
happened - the K2 wouldn't even turn on. Measuring my power supply voltage, it
was about 1 volt when plugged into the K2, but the normal 13.6 volts when not
plugged in. Opening up the K2, it was evident right away that the problem was
that the internal 12V wire between the K2 and the KPA100 was pinched between
the KPA100 shield and the side of the K2 and apparently shorting out somewhat
(but none of the fuses were blown). Taping the wires where the shield cut
through the insulation and moving the wires so the wouldn't be pinched fixed
that problem and now everything seemed to be working fine (or so I thought).
Then, on CW I tuned in a strong signal, and because there was lots of
QRM, hit the XFIL to a narrower filter, and the signal al shifted up a lot in
frequency and almost disappeared. It did completely disappear with a still
narrower filter. Going to SSB, there were lots of signals, but none of them
were intelligible. Checking the XFIL menu setting, they were all still as I had
set them, so this isn't a menu problem.
I then removed the KPA100 and the XFIL problem was still there. The
next step was to see just what the filters were doing using Spectrogram. The
broadest CW filter, which I had set to 1.6kHz, was more like 2.6 kHz (which
explains the QRM). The other filters, which I had set to 1.0, 0.6 and 0.3 kHz
were also about 30% broader and were all centered around 1.4kHz. For these
filters, changing the BFO down to a setting of 0 moved them down only to about
750Hz and there was no way to get them down to 600Hz. The LSB filters were
similarly messed up, with really messed up filter shapes. I adjusted them as I
could. Plugging in my antenna, CW signals were a little more readable, but not
much, and SSB was still unintelligible.
So, it appears that something broke, possible as a result of the
pinched 12 wire (but maybe not). Everything else besides the XFIL filters seems
to work. What controls the shape and center frequency of the XTAL filters and
where do I start looking for what's broken?
Thank you for any help and suggestions that you can offer.
Bob
W1SRB
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