Good method, Ed.
It can be in underground utilities too. It will propagate down the wires,
but will be strongest at one point.
At my location I used an AM broadcast band portable radio. I had a source
in new underground utilities in a new subdivision 1/2 mile to my north. Got
that fixed, then there was still a noise in the same direction. Tracked
that to a model home. Must have been some arc in the A/C or something.
Went back on Monday to tell them and there was an electrician already
there. All is quiet now!
Chuck W5PR
On Mon, Jan 16, 2017 at 2:50 AM, Ed Sawyer <sawyered@earthlink.net> wrote:
> Message: 5
>
> Date: Sun, 15 Jan 2017 11:31:43 -0500
>
> From: Paul Plants <w3plp@verizon.net>
>
> To: w5prchuck@gmail.com
>
> Cc: Jim Thomson <jim.thom@telus.net>, "towertalk@contesting.com"
>
> <towertalk@contesting.com>
>
> Subject: Re: [TowerTalk] noise profiles...
>
> Message-ID: <E043185A-6C48-4CE2-9EE9-66277B04B340@verizon.net>
>
> Content-Type: text/plain; charset=utf-8
>
>
>
>
>
> Paul,
>
>
>
> If you are driving around with an HF rig in your neighborhood, you will
> have
> a hard time finding interference that way. What I usually assume is that
> the noise source is generating signals in the UHF spectrum as well. I tend
> to walk, not drive, around with a 450Mhz Yaesu HT that has AM mode -
> connected to a 6 el hand held yagi - and headphones. As you walk past each
> pole, transformer, and house, point the yagi at the items to see if any
> noise rises up from the noise floor. Typically - interference is no more
> than 1 mile from your house (air mile) - often closer - if its S7+. I have
> yet to not find the offender using this method. Once a suspecting source
> has been zero'd in on, use the "deep null" feature of a 6 el yagi and see
> where the nulls are (better rays than the max gain of the yagi). Try and
> identify the source from at least 3 different sides to be sure its actually
> where you keep thinking it is - often its not quite where you thought it
> was.
>
>
>
> 73
>
>
>
> Ed N1UR
>
>
>
>
>
> Paul
>
> W3PLP
>
> Sent from my iPad Air 2
>
>
>
> > On Jan 15, 2017, at 11:18 AM, <w5prchuck@gmail.com> <w5prchuck@gmail.com
> >
> wrote:
>
> >
>
> > ?I have a noise, what do you think it could be?? doesn?t give us much to
> go on. Can you give us more information?
>
> >
>
> > Does the signal level vary with frequency? No
>
> > Does the level vary with direction? No
>
> > How are you looking for it? With what? Yeasu ssb radio
>
> > Surely it must be somehow localized to some area. How big? So far 2 mile
> radius and still looking
>
> > Have you checked close to power lines? Is it louder there? No
>
> > Have you checked close to cable tv lines? No
>
> > Have you determined it is not in your shack? Not. Did pull mains three
> times
>
> >
>
> Signal drops off sharp below 18 MHz and above 30 mhz
>
> >
>
>
>
> _______________________________________________
>
>
>
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