I'll throw my 0.02USD in as well. I use the MFJ-1026 and I found it to work
best when my noise antenna was receiving about the same amount of noise as
my main antenna. My main antenna at the time was a 40M horizontal loop up
35', the noise antenna ended up being 50' of wire helically wound on a 10'
crappie fishing pole. I noticed using the noise antenna gain on the MFJ
could lead to distortion at the higher settings so I kept it set below 3 on
the dial - whatever that meant. I made a video using the MFJ :
https://youtu.be/tTBKULHn8Rw and a comprehensive RFI video :
https://youtu.be/K_1hBFMzbAs
73! Mark KA6WKE
Youtube: https://www.youtube.com/ka6wke
Website: https://www.ka6wke.net
On Wed, Jan 13, 2021 at 10:54 AM myles landstein <myles.landstein@gmail.com>
wrote:
> I’ll also throw in, if you're using the anc4 as designed. I did find it
> very helpful for getting rid of a few kinds of noise in few specific
> circumstances , worked great.
>
> your millage my vary
>
> regards
> n2ehg
> myles
>
> > On Jan 13, 2021, at 1:20 PM, Cianciolo, Paul, W1VLF <pcianciolo@arrl.org>
> wrote:
> >
> > I call it "quality noise"
> > You want just your target noise to invert and cancel.
> >
> > Anything else will tend to add "new" noises from the pickup antenna.
> > See here
> >
> > https://youtu.be/spre7Wn0Kqs
> >
> >
> > 73,
> >
> > Paul Cianciolo, W1VLF
> > ARRL EMC Engineer
> >
> > ARRL - The national association for Amateur Radio™
> > 225 Main Street, Newington, CT 06111-1400 USA
> > Telephone: (860) 594-0392
> > FAX: (860) 594-0259
> > Email: w1vlf@arrl.org
> > World Wide Web: www.arrl.org
> >
> >
> >
> > -----Original Message-----
> > From: RFI <rfi-bounces+pcianciolo=arrl.org@contesting.com> On Behalf Of
> Mike Martin
> > Sent: Wednesday, January 13, 2021 11:57 AM
> > To: Dave Cole <dave@nk7z.net>
> > Cc: rfi@contesting.com
> > Subject: Re: [RFI] Sense antenna for ANC-4 power line rfi?
> >
> > Hey guys consider this, you can look at a noise on two antennas exactly
> the same but located in different places in your yard and see different
> noises. That's a fact.
> > So if you're using a noise cancellation device you can't expect the
> antenna you're using for that device to see the same noise that you see
> when the antenna with the symptoms. So you have to make sure that the
> cancellation device antenna is seeing the same noise that you're picking up
> in your receivers and causing interference to the one it's signal. once you
> achieve that then the noise cancellation device will work quite well. but
> if your noise cancellation device sees a different noise then you're
> canceling the wrong noise therefore it doesn't work properly. I wish I had
> more time to explain further but unfortunately I'm out here looking for
> noise and don't have the time.
> > Just so you know I also don't have time to proofread my voice to text
> message so please excuse the mistakes and type of graphical errors. LOL
> >
> > Happy 2021,
> > Mike
> >
> > Get BlueMail for Android
> >
> > On Jan 13, 2021, 9:15 AM, at 9:15 AM, Dave Cole <dave@nk7z.net> wrote:
> >> Charles,
> >>
> >> You may find that the phase type noise reducers don't work so well on
> >> power line noise... It can help-- but mostly it will not be very
> >> effective for distributed RFI sources.
> >>
> >> The source of transmission can be distributed, (not in all cases),
> >> along several hundred, to several thousand feet of power line. This
> >> means that depending on the distance traveled down the power line, the
> >> distance to your sense antenna, and the distance to your main antenna,
> >> RFI will arrive at different times, and hence different phase
> >> relationships to each other, from every point along the power line that
> >>
> >> carries the RFI.
> >>
> >> Given that the ANC-4 is a phase cancellation device, (it looks at your
> >> main antenna, and your sense antenna, and tries to phase cancel an RF
> >> signal based on phase relationship), this can cause no end of issues.
> >>
> >> Now imagine the signals the ANC will see if your RFI is being
> >> re-radiated along several hundred, or thousand feet of power line. You
> >>
> >> will be able to cancel some, but not a lot of the RFI.
> >>
> >> If you are lucky, you will have a specular source, and no re-radiation,
> >>
> >> which will allow you to cancel most of the offending signal out...
> >>
> >> Your idea is a good one, and might help... RFI suppression is always
> >> fun, when it works... Good luck. Please do post your results.
> >>
> >> 73, and thanks,
> >> Dave (NK7Z)
> >> https://www.nk7z.net
> >> ARRL Volunteer Examiner
> >> ARRL Technical Specialist, RFI
> >> ARRL Asst. Director, NW Division, Technical Resources
> >>
> >> On 1/12/21 11:07 PM, Charles Plunk wrote:
> >>> While waiting on my powerline arc to return in force enough to have
> >>> confidence it will be ongoing when I call TVA in, thought I would
> >> play
> >>> with improving the sense antenna on my Timewave ANC-4. The 3 phase
> >> power
> >>> runs at the edge of my lot up to the suspect pole. So the noise is
> >>> radiating up this way and all the more reason its strong on me I
> >>> suspect. I have a storage building underneath the lines. I am
> >> thinking
> >>> about a vertical made for a scanning receiver I came across and
> >> mounting
> >>> it up under the lines on that building. I will tack it up there
> >> somehow
> >>> and move it around to get a sweet spot maybe. Any better ideas?
> >>>
> >>> Thanks,
> >>> Chuck
> >>> AF4O
> >>>
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