First of all, thank you for all the input both privately and thru the
reflector. I find this group helpful, professional and pretty darn
knowledgeable. The absolute smoking gun was not identified, but the
following was done and now the signal has been given a clean bill of health
by several folks both near and far. My suspicion is that I had
inadvertently gotten RF into the shack and the cw rise time was much shorter
than what was indicated on the menu. For the record the key clicks had been
noticed while running 100W i.e. no amp. I had earlier noted that I had
hooked my o-scope to observe the keying waveform and it looked fine to my
untrained eye and compared well to what is published in ARRL handbooks as
acceptable keying waveform - nothing learned here per-se, but it was nice to
see the RF envelope. OK here is what I did after reading quite a bit from
W8JI and others that had published data on the internet.
1. I had noticed the radio was acting a little sluggish in band changes
recently, so I simply did a master reset. Monitor radio still indicated a
possible problem.
2. Rechecked all connectors to make them "wrench tight" All were tight to
the hand but about another 30 degrees of closure was gained by using a small
pipe wrench. Did not check clix at this time.
3. Increased CW rise time to max 10ms, based on some internet data that
showed the actual risetime to be about 50% of what is displayed.
I was able to check the signal and was given a clean bill of health on 40,
15 and 20M from the nearby friend station that had warned me of the key
clicks. We checked these bands at 100W and with the amp on at about 500w.
Not satisfied yet.
4. RF sniffed the RX antenna coming into the shack while transmitting. Hmm,
something there, but not much. Note that RX antenna is a K9AY loop and the
RX antenna was not being used at the time, but maybe RF getting in?? It is
in close proximity to the transmit antennas I only use the K9AY on 80M and
other than VK9HR, probably not needed right now. Unplugged it. The only
reason I checked this was based on some info from another friend that
mentioned it as a possible source of key clix. Interestinly, I had buried
the coax and control line about a day before the clix surfaced -
coincidence?? - not sure.
5. Improved the RF ground in the shack. Not sure this will aid in this
instance, but it is something that should have been pursued earlier.
6, Replugged in the K9AY loop and still all is ok.
Long story short, here is what my gut is telling me. Prior to the master
reset, the cw rise time had changed somehow to put the radio at risk of
clicking. The master reset along with increasing the rise time from 5ms to
10ms brought this under control. RF may had increased in the shack owing to
coax ( I used some pretty old coax when putting up the K9AY) being buried
and these conspired to make for problems.
Once again, thank you for all the help and advice. Clean signals are in
everyone's interest eh?!
Karl KD8GOX
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