Hi Ed,
Sorry, but I no longer have it... It was ugly and hand drawn contour
lines... I now use Google Maps and GIMP to draw things... They look
much better that way!
If you want, I can send you, (not on the list), the package of data I
collect for the FCC should a RFI situation get out of hand, and need to
be reported...
BTW, the walk around was at 135 MHz, just above the Aircraft band in AM
mode... I use one of those little MFJ 135 MHz broadband VHF beams,
works like a champ most of the time.
--
Thanks and 73's,
For equipment, and software setups and reviews see:
www.nk7z.net
For MixW support see;
http://groups.yahoo.com/neo/groups/mixw/info
For Dopplergram information see:
http://groups.yahoo.com/neo/groups/dopplergram/info
For MM-SSTV see:
http://groups.yahoo.com/neo/groups/MM-SSTV/info
On Tue, 2015-07-28 at 17:57 +0000, Hare, Ed W1RFI wrote:
> I'd love to see that graph, or the measured data, if you still have it. It
> may be useful on RFI web pages or publications.
>
> -----Original Message-----
> From: RFI [mailto:rfi-bounces@contesting.com] On Behalf Of David Cole
> Sent: Monday, July 27, 2015 10:14 PM
> To: rfi@contesting.com
> Subject: Re: [RFI] Other Noise Challenge For Ed!
>
> 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,
> For equipment, and software setups and reviews see:
> www.nk7z.net
>
> For MixW support see;
> http://groups.yahoo.com/neo/groups/mixw/info
> For Dopplergram information see:
> http://groups.yahoo.com/neo/groups/dopplergram/info
> For MM-SSTV see:
> http://groups.yahoo.com/neo/groups/MM-SSTV/info
>
>
> 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
> >
> > _______________________________________________
> > RFI mailing list
> > RFI@contesting.com
> > http://lists.contesting.com/mailman/listinfo/rfi
>
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