This is also why the phase canceling devices fail to work on this sort
of RFI as well... No point source.
--
73's, and thanks,
Dave (NK7Z)
For software/hardware reviews see:
http://www.nk7z.net
For MixW support see:
https://groups.yahoo.com/neo/groups/mixw/info
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http://groups.yahoo.com/neo/groups/MM-SSTV/info
On Tue, 2016-03-08 at 21:19 +0000, Hare, Ed W1RFI wrote:
> I can't imagine this reliably working well. If noise gets onto long,
> overhead power lines, it will radiate for a long distance. The noise
> radiated by lines closer to the shack than the actual source will
> often skew off the apparent azimuth angle, even if beam nulls and
> bisecting the angles are used to get a bearing, it is going to thrown
> off to one degree of another by nearby radiation, re-radiation and
> scatterers. The technique described will give a better heading most
> of the time than trying to use the mail lobe of a 3-element Yagi on
> HF, but I really wouldn't trust it to accurately pinpoint the pole.
>
> If hams report poles needing fixing and the utility does a truck roll
> or two to fix them, it will hard to get them to do another one, so
> don't be complacent; go out into the field with a VHF Yagi and
> receiver and either use signature-analysis techniques or trace that
> noise all the way from your house to the actual source. If you wear
> out your welcome with the power company by being wrong, it will be
> hard to get a new welcome.
>
> Ed Hare, W1RFI
>
>
>
> -----Original Message-----
> From: RFI [mailto:rfi-bounces@contesting.com] On Behalf Of Michael C
> Martin
> Sent: Tuesday, February 16, 2016 8:53 PM
> To: donovanf@starpower.net; topband@contesting.com; rfi@contesting.co
> m
> Subject: Re: [RFI] Topband: Tecsun 660
>
> If Stan's friend is that lucky he should attend the casino with me.
>
> Sent with AquaMail for Android
> http://www.aqua-mail.com
>
>
> On February 16, 2016 4:25:01 PM donovanf@starpower.net wrote:
>
> >
> > Hi Stan,
> >
> >
> > There are countless thousands of poles within five miles of my
> > QTH,
> > his method could not possibly work here. If I tried, I would lose
> > my
> > excellent reputation with my power company RFI crew.
> >
> >
> >
> > I prefer to leave my shack and verify the pole rather than
> > guessing
> > which one it might be. Its not difficult and a little exercise is
> > a
> > good thing!
> >
> >
> > tks
> >
> >
> > 73
> > Frank
> > W3LPL
> >
> > ----- Original Message -----
> >
> > From: "Stan Stockton" <wa5rtg@gmail.com>
> > To: donovanf@starpower.net
> > Cc: "Top Band Contesting" <topband@contesting.com>, rfi@contesting.
> > com
> > Sent: Tuesday, February 16, 2016 5:19:55 PM
> > Subject: Re: Topband: Tecsun 660
> >
> > Frank,
> >
> > I have a friend who has used the RF Gain control as needed,
> > balanced
> > antenna and accurate, equal measurement of the strength of the
> > noise
> > off center by an equal number of degrees CW and CCW from the
> > actual
> > direction to determine with great accuracy the direction of the
> > noise.
> > Then plotting a line using GPS mapping has actually called the
> > power
> > company telling them the exact pole where the problem is located
> > without ever leaving his shack.
> > He said he could have given them the pole number where the line
> > went
> > right through the pole on the map except for the fact that they
> > had
> > blacked out the number like they do on license plates. The address
> > had to suffice.
> > Pretty neat!
> >
> > 73... Stan, K5GO
> >
> > >
> > > On Feb 16, 2016, at 9:18 AM, donovanf@starpower.net wrote:
> > >
> > > Hi Jeff,
> > >
> > >
> > > My consistent practice is to identify the highest frequency where
> > > I
> > > can hear the RFI in my shack. I then use my directive antennas
> > > to
> > > determine the bearing on which I should search. I can
> > > consistently
> > > determine azimuth within better than ten degree accuracy on any
> > > band.
> > > I begin my search on that frequency with the PL-660 in wide band
> > > AM
> > > mode, walking or driving along the line of bearing.
> > >
> > >
> > > The PL-660 has a built in loopstick antenna very useful for
> > > direction
> > > finding but active only in the AM broadcast band
> > > (540-1700 kHz). Above 1700 kHz it uses a short retractable whip
> > > antenna (slightly useful for direction finding) or an external
> > > antenna.
> > >
> > >
> > > Usually (but definitely not always) the RFI can be heard on
> > > higher
> > > frequencies as you get closer to the source, in many cases up the
> > > the
> > > aircraft band or all the way up to 450 MHz (on a different
> > > receiver).
> > > So far my most distant RFI was AC power line RFI very strong at
> > > my
> > > QTH that originates four miles away, It was a serious visible arc
> > > on
> > > a 34 kV subtransmission line (not a local
> > > 13 kV distribution line). The power company was very motivated
> > > to
> > > repair it quickly.
> > >
> > >
> > > This recent RFI was very different than anything I've ever
> > > experienced, I could hear the RFI only on the 160 meter band
> > > (about
> > > 1500- 2000 kHz) It sounded like white noise with no audible 60 Hz
> > > (or
> > > 60 Hz harmonic) component, The only way I could locate it was by
> > > using the PL-660 S-meter with the PL-660 in wideband AM mode. It
> > > turned out to be a malfunctioning Travellers' Information
> > > Station
> > > transmitter at 1700 kHz. Local hams have an excellent
> > > relationship
> > > with the county Office of Emergency Management that operates the
> > > transmitter and they turned it off within hours of being notified
> > > of
> > > the problem.
> > >
> > >
> > > This is only the second RFI that I've experienced that affects
> > > only
> > > 160 meters. The first one was very intense RFI that sounded
> > > exactly
> > > like classic AC power line RFI but strangely it affected only
> > > 160
> > > meters and the AM broadcast band.
> > > It turned out to be a malfunctioning electric fence charger one
> > > mile
> > > away that was stuck continuously on, not pulsing.
> > > Unfortunately the landowner (an electrician!) was very
> > > belligerent
> > > about refusing to replace his fence charger, but some aggressive
> > > "social engineering" motivated him to change his behavior.
> > >
> > >
> > > 73
> > > Frank
> > > W3LPL
> > >
> > >
> > > ----- Original Message -----
> > >
> > > From: K1ZM@aol.com
> > > To: donovanf@starpower.net
> > > Sent: Tuesday, February 16, 2016 10:08:22 AM
> > > Subject: Tecsun 660
> > >
> > > Hi Frank
> > >
> > > I read your emails on your RFI search.
> > >
> > > Youmay have mentioned it, but what FREQ BAND did you use on the
> > > TECSUN in your search for the source?
> > >
> > > Was it the AIRCRAFT BAND on FM?
> > >
> > > The reason I ask is that I have a similar radio - that is very
> > > similar to the radio you used - just made by SONY.
> > >
> > > I wonder if I could use it like you did? I am 99% sure it has
> > > the
> > > aricraft FM band in it.
> > >
> > > Pls let me know when you can.
> > >
> > > Tks
> > >
> > > 73 JEFF</HTML>
> > >
> > > _________________
> > > Topband Reflector Archives - http://www.contesting.com/_topband
> > _______________________________________________
> > RFI mailing list
> > RFI@contesting.com
> > http://lists.contesting.com/mailman/listinfo/rfi
>
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