Hi Tom,
Lots of people helping you so I’ve stayed silent but let me make a couple
comments related to your most recent comments. If you have a radio that
tunes down into the VHF aircraft band it will typically automatically
switch to AM mode (my old Icom T7H HT switches to AM if I tune below
136.000 MHz) and it works well for DFing power line noise as does the cheap
handheld police scanner that I normally use with a 4 element 2 meter beam
in which I lengthened the elements using alligator clips (each half of the
element lengthened 1.4 inches) so it maintains a good front to back ratio
at 136 MHz.
Also most modern car radios have such good noise blankers that they don’t
necessarily hear powerline noise very well. My 1996 Saturn has a great
radio for powerline noise and electric fence monitoring whereas my wife’s
newer car as well as other newer cars I listened to don’t hear powerline
noise or electric fence noise worth a darn compared with my 1996 vintage AM
car radio.
Your noise is so strong on 20 meters that you should also be able to build
my portable flag and hear that RFI on 20 meters from outside your house and
probably need an external preamp. Very simple antenna to build and it’s
unidirectional which makes DFing so much easier than using a bidirectional
loop.
73,
Don wd8dsb
On Tue, Dec 31, 2024 at 5:52 PM thoyer1--- via RFI <rfi@contesting.com>
wrote:
> Thanks for the suggestions.
>
> I have toured the immediate neighborhood with the car radio at 1710. I
> don’t hear anything out of the ordinary as I know where most of the “noisy”
> spots have been for years so it has to be further out.
>
> Peak noise is due north on 20m it gets weaker the higher I go to the point
> of barely hearing it on 2M – only have FM/SSB 2M rig, no AM.
>
> Tom
> W3TA
>
> -----Original Message-----
> From: RFI <rfi-bounces+thoyer1=verizon.net@contesting.com> On Behalf Of
> Alan Higbie
> Sent: Monday, December 30, 2024 4:35 PM
> To: Rfi List <rfi@contesting.com>
> Subject: Re: [RFI] Fwd: Power Line Noise
>
> Perhaps it fades off higher in the band (in the phone portion) because
> your antenna is more responsive down in the CW segment?
>
> Do you know what direction it's coming from? Try peaking it with your beam.
> It may be a sharper peak on higher band - like 10 meters. I'd also try
> using your 6 meter and 2 meter beams to do the same in that direction for
> possibly even sharper peak. (set to receive on AM)
>
> Then take a handheld VHF / UHF radio (on AM) and walk out in that
> direction until you find the pole where it is strongest. That may provide
> some further clues as to exactly which pole is the source. After all . . .
> there is some specific source out there causing the problem.
>
> Knowing which pole is the source, will help your power company crew fix it
> faster.
>
> Please keep us posted. That way, we all benefit.
>
> 73,
>
> ~ Alan K0AV
>
> On Mon, Dec 30, 2024 at 9:09 AM Dave (NK7Z) <dave@nk7z.net> wrote:
>
> > Hi Tom,
> >
> > While you wait for the local power company you might consider
> > reviewing
> > this:
> >
> > https://www.nk7z.net/i-have-rfi-now-what-locating-it/
> >
> > then running a RFI site survey of your area before the power company
> > get out there... You can do a before, and after, with this process:
> >
> > https://www.nk7z.net/sdr-rfi-survey-p1/
> >
> > 73, and thanks,
> > Dave (NK7Z)
> > https://www.nk7z.net
> > ARRL Volunteer Examiner
> > ARRL Technical Specialist, RFI
> > ARRL Asst. Director, NW Division, Technical Resources
> >
> >
> > On 12/30/24 05:39, thoyer1--- via RFI wrote:
> > > This past fall I've been plagued with noise wiping out the lower end
> > > of 20m (I'm a CW op so this is a big problem). I fades off above
> > > 14.200, but I can still hear it...
> >
> > _______________________________________________
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> > RFI@contesting.com
> > http://lists.contesting.com/mailman/listinfo/rfi
> >
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