Based on recommendations from this reflector, and from Ed Hare, I have a
process defined that should give me a good baseline.
The power line is scheduled to be back on-line on Friday. So my window of
opportunity is somewhat short. Tonight, Dewey-N0VO is going to come over with
his video camera. We are going to drive around the neighborhood with the
camera running and tuning around on the IC706MKIIG in the vehicle. The best
antenna I can muster will be a simple non-resonant 8' whip on the car. Doing a
comparable stunt after the first line is active (next week) and the second line
(maybe in a month or so) should provide more than ample evidence as to who's
line is spewing RF.
Last night, I used my HP-141T analyzer to document what my main station antenna
hears. I cannot believe how quiet it is right now. I have to key down just to
make certain the antenna is really connected!
Based on Ed Hare's recommendation, I am using the 8553B plug-in (0.1-11MHz;
10-110MHz) to listen on the main antenna in each of the ham bands. Setting
the bandwidth to 3KHz, centering the scope somewhere in each of the ham bands,
I clicked off two pictures of the scope display at each frequency. The first
picture has a 50 ohm termination on the scope, the second has the antenna.
Unfortunately, the noise floor of the analyzer is only -80dBm to -90dBm, so
connecting the antenna does not elevate the noise floor. This is still good
evidence as looking at that same display previously with the power lines
active, the displays of power line hash noise is often in excess of -20dBm. I
am going to re-visit this on Thursday with Ray-KE3QY. He's bringing a portable
scope with a GPIB port for printing. I will put a 20dB pre-amplifier on the
antenna (HP-461A; 1KHz to 150MHz) and see if I can elevate my natural noise
floor enough to see it on the scope.
Thanks to everybody for the help. This could prove very interesting.
Ford-N0FP
ford@cmgate.com
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