Hi, all.
First of all, I want to apologize for not being able to hold down net
control for the Cross-country blind ops net this afternoon.
I seem to have developed an interesting RFI problem with my Alpha Delta DXCC
antenna, and am trying to troubleshoot it.
You may recall that, several weeks ago, I was unable to tune up my amplifier
on our 20-meter frequency, because it was tripping off my Astron RS35 power
supply.
I solved that problem by grounding the power supply, and by putting RF
chokes on the DC power cord to the TS480, and the cord that connects my
surge protector power strip to the AC wall outlet.
Well, apparently, my RFI problems aren't over.
Today, when trying to start the net, I got reports that my audio was
extremely garbled. So, needless to say, I spent net time trying to diagnose
the situation.
I had worked this week-end on setting up a computer at my operating desk, so
wondered if that was creating ground loop issues for me. When
systematically disconnecting the computer stuff, the garbled audio decreased
significantly, but was still there.
If I took things down to 100 watts, the audio was clear.
I then went down to 40 meters, and made some contacts in the North Carolina
QSO Party contest. On 40, even with the amp at 600 watts, my audio was
reported to be clear and crisp.
So, obviously, I'm getting RF back into the shack on 20 meters with the
DXCC.
I'm limited here on what I can do outside, since we still have about a foot
and a half of snow on the ground, but I'd be interested in anything anyone
could suggest to fix this problem with 20 meters.
I should point out that my rig, amplifier, tuner, and Astron power supply
are all grounded to the common ground lug on my window feed through panel,
and the ground lug on that panel is connected to a ground rod right outside
my shack window.
As I'm sure you can imagine, I am now getting more anxious than ever to get
my Windom back up.
73 from Tom Behler: KB8TYJ
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