Thank you very much for the replies! Five or six of you reported a
similiar problem of interference occuring every 10 KHZ.. This problem
definitely started about 2 weeks ago with the ice storm. Cutting to the
chase, Arliss-W7XU and myself spent all yesterday afternoon direction
finding with a 160 meter loop antenna as per the ARRL Antenna Handbook.
For a radio we used an IC-706. I want to credit Roger-N1RJ with one of
the most useful comments except it was one day late! What we appear to
have found is our ability to direction find my existing 160 antennas
which seemed to be re-radiating the interference. We did not realize it
as first as our first DF pointed right at the 1/4 wave 160 vertical. We
thought WOW there is nothing to this so we shake, beat, etc on it and
absolutely no change. We then spend about 1 hour shaking and pounding
on everything on my antenna farm with absolutely no results. Next we
freeze driving up and down the roads in all four directions from my place about
1/4 mile each way and hear nothing other than a far away electric
fencer and some power line noise and of course later in the afternoon
some 160 signals which means the best time for me to try and solve this
problem is during the day; especially with all the 160 amateur AM
activity.
We decided to DF again and this time we get a signal pointing right at
another tower. It seemed like there were "Hot Spots" like one
experiences on VHF. Anyway when it was all said and done we determined
the loudest DF signal was when we were exactly below on of my 160
dipoles with the loop in the same plane as the dipole.
We would of tried to drive around among the towers but there was to much snow.
We got stuck once the way it was. I am going to use a long
extension cord, several 100 feet and move around using my IC-736 and the
loop to see if I can determine anything else. Other than getting the
radiation when pointed right at a 160 antenna the signal is really weak
on the loop but on my regular antennas it is like S-6 or 7.
As soon as I get a power cord for the IC-736 I am going to use a small 12
VDC battery , the IC-706 and the loop antenna and try walking around through
the snow drifts trying to DF the interference.
How far away has anyone every found a "rectification" problem? Last
night I was thinking this "rectification" is really close but after
sleeping on it I am wondering if it is out there say 1/2 mile? The
reason I say this is how loud the signal is on my antenna's and how we
have trouble hearing it at all with the loop. Anybody have any real
experiences they could relate on distance!
Another idea that you also seen on the reflector is an actual AM
transmitter problem using a switching type modulator on one of the AM stations
that reportedly occurs every 10 KHZ. I am checking this out.
As my friend Arliss said after listening to the problem "this is not
acceptable" so I am going to keep fighting it and will report. One last
thing we had the Advance Intercept Point on and the attenuator in
and ran the antenna through a NYE tuner tuned to the 160 frequency and
we still had the "AM interference" on the TS-950SDX. It just seems
based on that and hearing it on three recievers the it has to be an
external signal but I'm trying to keep my mind open. When I get the
IC-706 again I am going to listen on it using the battery and kill the
main power at the pole to illiminate any other device that might be generating
a signal but I swear I have shut everything off in the house one
at a time at least twice. Any other ideas would be appreciated. I will
report again when I have something significant to report.
73, Ed-W0SD
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