Tracking down power line noise
I have been wrestling with power line noise here for almost a year.
Power company hasn't been very successful in locating it so I started a
coordinated search
on my own. Thinking if I can tell them for certain which poles have the
problem they can confirm and maybe fix.
The noise is a deafening 20 over 9 on 80 meters which makes DXing on 80 and
160 impossible.
The noise can be heard at my QTH as high as 10 and 6 meters but it isn't
troublesome on those bands because it can only be heard at about an S7 level
when the yagi is pointed at 210 degrees.
I thought maybe my means of analysis might be interesting to discuss and
maybe others would have other suggestions.
There are 7000 volt lines running on a highway past my house. Tracking the
source on 80m seems impossible.
I made a 2 ft square loop antenna, which has some directivity but the noise
level using it seems to not change
much as I travel the highway. On 10 meters, using a 4 ft whip on the car,
the noise is also hard to localize but
seems to increase in the vicinity of 1 mile from home. 6 meters using a
whip is similar. I found that if I'm close
enough that the 6 meter signal is around S7 I can switch to 2 meters and
again peak the noise by driving slowly up and down the road.
So using this technique and driving 2 miles in each direction I have managed
to find 2 spots, one on the highway and one on a cross road, each about 1.2
miles from the QTH. I then built a 432 MHz 8 element quagi beam which
enabled me to pinpoint the offending pole at these two locations. (I have
put a LOT of effort into this project !)
At this time I am waiting (hoping) for a return call from the power company
to verify my dicovery.
So my question for the group - Can either of these locations 1.2 miles
distant cause such horrendous noise levels on 80 meters? Is it possible
that a weaker noise source much closer to me is the culprit or are all of
the power line malfunctions detectable on 440 MHz?
Rick K2XT
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