During this past June's VHF contest, I found that I heard no stations on 222
cw, ssb, or FT8, and none answered my CQ's. This seemed odd. Digging into it
after the contest, I found that I could not even hear any beacon stations,
not even the regulars. Have they all gone off the air?
So, I started checking my end.
The antennas measured OK with a nanoVNA.
The Elecraft transverter made the expected transmit power.
The sequencer T/R relays were operating fine.
The bias voltages of the active devices in the 222 transverter receive path
seemed normal.
Then, using the nanoVNA as a signal source, I found that a 222.1 input
signal was about 1.2 MHz higher than it should have been at the IF freq! Has
the crystal LO shifted frequency? Weird. Tried to fire up my Airspy SDR to
verify, but Win 10 would not recognize it being plugged in. Wasted an
afternoon trying to get that to work without success. Fiddled with the
transceiver's LO inductor tuning, no luck. Sigh.
Plan B: Last year I built an external LO for my 432-transceiver using a nice
stable synthesizer PCB from Q5 Signal and incorporated an additional LO
output for 222 if ever needed. Guess it is time to modify the Elecraft to
use this LO source. Success! The beacons were received again and transmit
seemed normal.
Though my time was limited, last night was a good chance to test it in the
real world. Initially I heard many stations on ssb exchanging pleasantries.
And I think it might have been WZ1V's strange broken up CW coming in with
good strength.
Eventually I got everything else back together and fired up on FT-8 and
called without getting any answers for a while-hmmm? Then a loud WA3NUF
appeared. It took me a couple of sequences before correctly setting WSJT-X
to respond, and it was a quick Q, followed by one with K1WHS. Next I heard a
weak WA4VA in FN42 calling me but could not complete the contact. Seems 222
here is well again.
TU and 73,
Chet, N8RA
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