[RFI] Other Noise Challenge For Ed!

[David Cole]

Joe,

A few years ago, I had a RFI source from an area with underground
utilities.  I located a source by driving to each underground
transformer and taking a reading at 7 MHz, using a short antenna and a
standard procedure for pointing etc.  I wanted to have a standard way of
reading the signal levels.  I did the same thing at each transformer I
could find, then took the data and plotted it on a Google map of the
area, then hand drew contour curves to the various S meter levels I had
gotten...  Much to my surprise it formed a great big target ellipse.  I
think I got very lucky, but it might be worth a try for you.  I then
walked around with a 123MHz beam and TH-F6 in the suspect area.  

Found the house in short order...  Contacted the owner, and a few weeks
later the RFI was gone.

As Ed said, in each case, "First Contact" is so important...  If you
come on strong, and tell the person they are in violation of anything,
they get really quiet...  If you approach them as a neighbor, things go
really well...

-- 
Thanks and 73's,
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On Mon, 2015-07-27 at 18:09 -0700, Joe Wolfe wrote:
> 
> Ed, perhaps you can shed some sense to this.  Up until 4 years ago, I had no
> noise to speak of...1 to 2 s units, tops.
> 
> Then, one November day, I turned on the radio to 40 meters (7.205), at noon,
> and was blasted with a 20 over *white noise*.
> 
> Did not go away, and it permeated 75 meters as well.  20 and 17 are
> tolerable, 15 and up have acceptable noise levels.
> 
> Again, this is just very loud white noise, unwavering in pitch.
> 
> I hooked my radio (Kenwood TS-2000) to a battery, then switched of the main
> breaker, so no power was present in the house.  Noise was unchanged.
> 
> Further research revealed:  On 40, the noise dropped to below 3 S units, and
> stayed low all night.  Around 9-10 in the morning, the noise starts to rise,
> reaching its crescendo around noon.  75 meter  noise does not decrease much,
> at any time of day or night.
> 
> I have walked the neighborhood with the AM radio, Kenwood TH-F6A, and
> found....nothing.
> 
> The noise is present in all HF radios I have, Drake's, Yaesu's, even tried
> an ICom..
> 
> Mobile HF, drive 2 miles away, and the noise is gone.
> 
> There are no overhead wires in my neighborhood.  There is a high tension
> line 2 miles from the house, but it is quiet it's 8 miles run, down to town
> from the crest of the mountain it comes across from the North.  (I have
> driven it)
> 
> I run an off-center fed dipole, 6 to 80 meters, at 20 feet on 1 side, 26
> feet the other side.  (Fence is on a drop down berm..we live in the hills
> (Each house in the neighborhood is 6 to 8 feet higher [or lower] than its
> neighbor]) I have no problems being heard anywhere, on any band, but...heh,
> if you can't hear, what the sense?!!!
> 
> Thoughts?
> 
> Joe Wolfe - W7RKN
> 
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