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[RFI] Power Line Radiated Interference Limits

To: <rfi@contesting.com>
Subject: [RFI] Power Line Radiated Interference Limits
From: "Riki, K7NJ" <k7nj@awinets.com>
Date: Mon, 6 Jun 2022 21:42:36 -0600
List-post: <mailto:rfi@contesting.com>
A few more notes:
The farthest source that I located is about 7 miles away, and the closest
one is about 1.5 miles away. As mentioned before, there may be more, but for
now, this is a good starting point.
I was able to DF the approximate direction with the help of three
bi-directional Beverages. So, I generally knew in what direction to search
in. In summary, nothing sophisticated was used - just a simple, common
sense, basic ham approach. 
73, Riki K7NJ

-----Original Message-----
From: RFI [mailto:rfi-bounces+k7nj=awinets.com@contesting.com] On Behalf Of
rfi-request@contesting.com
Sent: Monday, June 06, 2022 8:29 PM
To: rfi@contesting.com
Subject: RFI Digest, Vol 233, Issue 5

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Today's Topics:

   1. Re: Power Line Radiated Interference Limits (Charles Plunk)
   2. Re: Power Line Radiated Interference Limits (AA5CT)
   3. Re: Power Line Radiated Interference Limits (Steve Dyer)
   4. Re: Power Line Radiated Interference Limits (Charles Plunk)
   5. Re: Power Line Radiated Interference Limits (Dave (NK7Z))


----------------------------------------------------------------------

Message: 1
Date: Mon, 6 Jun 2022 19:15:12 -0500
From: Charles Plunk <af4o@twc.com>
To: rfi@contesting.com
Subject: Re: [RFI] Power Line Radiated Interference Limits
Message-ID: <1dc6f868-2232-ec93-0d52-3aa7891b174b@twc.com>
Content-Type: text/plain; charset=UTF-8; format=flowed

I snooped on your QTH. Nice remote area with single phase lines. I am 
jealous :-).

73 Chuck W4NBO


On 6/6/22 18:21, Riki, K7NJ wrote:
> Thanks Ed and Charles,
>
> With all the great input from Ed, I now know the "lay of the land", i.e.
> what administrative tools and regulations apply.
>
> I've located two power poles that are likely sources.  I drove around
> listening on my car radio to the noise in a clear channel in the AM
> broadcast band. When the noise peaked next to a power pole, I got out of
the
> car and did some direction finding with a portable AM radio (that has the
> typical directional internal antenna).  Next, I verified the findings
using
> an MFJ-852 AC Power Line Noise meter. Everything was in agreement, so I
made
> note of the pole identification number (from its metal ID label).  I've
> already contacted the power company, and they've issued a work order
number.
> They said that it might take a week or two, and if needed, I should call
> them back.
>
> Hopefully the problem will now be fixed, although there were many
additional
> power poles that caused much lower noise on the car radio.  But, this is a
> good starting point for now.
>
> 73, Riki K7NJ
>
> -----Original Message-----
> From: RFI [mailto:rfi-bounces+k7nj=awinets.com@contesting.com] On Behalf
Of
> rfi-request@contesting.com
> Sent: Monday, June 06, 2022 5:28 AM
> To: rfi@contesting.com
> Subject: RFI Digest, Vol 233, Issue 3
>
> Send RFI mailing list submissions to
>       rfi@contesting.com
>
> To subscribe or unsubscribe via the World Wide Web, visit
>       http://lists.contesting.com/mailman/listinfo/rfi
> or, via email, send a message with subject or body 'help' to
>       rfi-request@contesting.com
>
> You can reach the person managing the list at
>       rfi-owner@contesting.com
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of RFI digest..."
>
>
> Today's Topics:
>
>     1. Power Line Radiated Interference Limits (Riki, K7NJ)
>     2. Re: Power Line Radiated Interference Limits (Charles Plunk)
>     3. Re: Power Line Radiated Interference Limits (Charles Plunk)
>     4. Re: Power Line Radiated Interference Limits (Hare, Ed, W1RFI)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Sun, 5 Jun 2022 20:12:02 -0600
> From: "Riki, K7NJ" <k7nj@awinets.com>
> To: <rfi@contesting.com>
> Subject: [RFI] Power Line Radiated Interference Limits
> Message-ID: <000401d8794a$d01cf890$7056e9b0$@com>
> Content-Type: text/plain;     charset="us-ascii"
>
> I've recently become plagued by power line interference that is most
> noticeable on 80M and 160M.  In the past,, the local power company had
been
> cooperative in fixing the source(s) of such interference.  However it's
been
> about 7 or 8 years since I've been in touch with them about such issues.
> Just to be prepared, I would like to know what specific limits there are
on
> power line emissions (if any).  I know that in the past, the requirements
> were very lenient - only requiring power companies to follow good
> engineering practice without any quantitative emission limits.  In any
case,
> having the actual reference paragraph numbers in the FCC rules would be
most
> helpful. As I recall, this had been somewhere in Part 15. Any help would
be
> appreciated.
>
> 73, Riki K7NJ
>
>
>


------------------------------

Message: 2
Date: Tue, 7 Jun 2022 01:08:40 +0000 (UTC)
From: AA5CT <jwin95@yahoo.com>
To: "rfi@contesting.com" <rfi@contesting.com>, Charles Plunk
        <af4o@twc.com>
Subject: Re: [RFI] Power Line Radiated Interference Limits
Message-ID: <936942320.93901.1654564120029@mail.yahoo.com>
Content-Type: text/plain; charset=UTF-8

Won't he be surprised when it DOESN'T cure the problem; I just
tracked down a source I had on 160 meters that was 1.74 miles 
 (that's one point seven four miles) away. This was 'tracked' down 
using a portable battery-operated marine DF receiver using a 
bicycle as mode of transportation. Multiple DF readings were
taken on this source until I finally converged on the source.

Some of these sources can be quite some distance away, and any 
nearby sources located may not be the one creating all the havoc
at the station QTH. I've had a couple of those, too. By using the 
DF receiver I can take bearings some distance out from the 
actual, final 'source' and feel quite confident I've located the 
source that affected my station QTH. Also note, when I find 
one of these sources a mile or more out, standing 30 feet away
from the actual source the noted signal strength is quite strong.
I make use of and note of the RF gain control setting on the DF 
receiver too. As there is no AGC on these model marine DF receivers,
its necessary to 'wind back' the RF gain as one begins to converge
on the noise source. One gets a repeatable indication when locating
these sources and noting that the RF gain setting is near minimum 
to keep the meter 'mid-range on scale' when one finally locates the
actual, physical RFI source.

de AA5CT Jim
 

    On Monday, June 6, 2022, 7:15:24 PM GMT-5, Charles Plunk <af4o@twc.com>
wrote:  
 
 I snooped on your QTH. Nice remote area with single phase lines. I am 
jealous :-).

73 Chuck W4NBO


On 6/6/22 18:21, Riki, K7NJ wrote:
> Thanks Ed and Charles,
>
> With all the great input from Ed, I now know the "lay of the land", i.e.
> what administrative tools and regulations apply.
>
> I've located two power poles that are likely sources.? I drove around
> listening on my car radio to the noise in a clear channel in the AM
> broadcast band. When the noise peaked next to a power pole, I got out of
the
> car and did some direction finding with a portable AM radio (that has the
> typical directional internal antenna).? Next, I verified the findings
using
> an MFJ-852 AC Power Line Noise meter. Everything was in agreement, so I
made
> note of the pole identification number (from its metal ID label).? I've
> already contacted the power company, and they've issued a work order
number.
> They said that it might take a week or two, and if needed, I should call
> them back.
>
> Hopefully the problem will now be fixed, although there were many
additional
> power poles that caused much lower noise on the car radio.? But, this is a
> good starting point for now.
>
> 73, Riki K7NJ
>
> -----Original Message-----
> From: RFI [mailto:rfi-bounces+k7nj=awinets.com@contesting.com] On Behalf
Of
> rfi-request@contesting.com
> Sent: Monday, June 06, 2022 5:28 AM
> To: rfi@contesting.com
> Subject: RFI Digest, Vol 233, Issue 3
>
> Send RFI mailing list submissions to
> ??? rfi@contesting.com
>
> To subscribe or unsubscribe via the World Wide Web, visit
> ??? http://lists.contesting.com/mailman/listinfo/rfi
> or, via email, send a message with subject or body 'help' to
> ??? rfi-request@contesting.com
>
> You can reach the person managing the list at
> ??? rfi-owner@contesting.com
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of RFI digest..."
>
>
> Today's Topics:
>
>? ? 1. Power Line Radiated Interference Limits (Riki, K7NJ)
>? ? 2. Re: Power Line Radiated Interference Limits (Charles Plunk)
>? ? 3. Re: Power Line Radiated Interference Limits (Charles Plunk)
>? ? 4. Re: Power Line Radiated Interference Limits (Hare, Ed, W1RFI)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Sun, 5 Jun 2022 20:12:02 -0600
> From: "Riki, K7NJ" <k7nj@awinets.com>
> To: <rfi@contesting.com>
> Subject: [RFI] Power Line Radiated Interference Limits
> Message-ID: <000401d8794a$d01cf890$7056e9b0$@com>
> Content-Type: text/plain;??? charset="us-ascii"
>
> I've recently become plagued by power line interference that is most
> noticeable on 80M and 160M.? In the past,, the local power company had
been
> cooperative in fixing the source(s) of such interference.? However it's
been
> about 7 or 8 years since I've been in touch with them about such issues.
> Just to be prepared, I would like to know what specific limits there are
on
> power line emissions (if any).? I know that in the past, the requirements
> were very lenient - only requiring power companies to follow good
> engineering practice without any quantitative emission limits.? In any
case,
> having the actual reference paragraph numbers in the FCC rules would be
most
> helpful. As I recall, this had been somewhere in Part 15. Any help would
be
> appreciated.
>
> 73, Riki K7NJ
>
>
>
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http://lists.contesting.com/mailman/listinfo/rfi
  

------------------------------

Message: 3
Date: Mon, 6 Jun 2022 18:19:45 -0700
From: Steve Dyer <w1srd@yahoo.com>
To: rfi@contesting.com
Subject: Re: [RFI] Power Line Radiated Interference Limits
Message-ID: <3a62b5ee-7216-d7e7-dd0b-961f7ecee318@yahoo.com>
Content-Type: text/plain; charset=UTF-8; format=flowed

For a quick and easy reading, the WSJT-X waterfall is quite useful. Just 
drop the rig into AM mode and see the bright line at 120 Hz and 
harmonics every 60 Hz across the whole pass band (at least at my QTH). 
Be sure to set Start to 0 Hz. You can roll over the waterfall or the pan 
with the cursor and read out the frequency.
I've also used Spectrum Lab to capture audio artifacts.
Soundcard Oscilloscope is useful to identify when you have multiple 
sources by observing the pulse trains and measuring the times between 
pulses. https://www.zeitnitz.eu/scope_en
Cant have too many tools.
73,
Steve
W1SRD

On 6/6/2022 13:24, Hare, Ed, W1RFI wrote:
> Actually, much powerline noise is rather steady, so it will show up as a
solid block on a waterfall.  That is diagnostic that the noise is not coming
from a switcher, but will not differentiate conclusively between electrical
noise and perhaps noise caused by something not powerline-related at all.
The waterfall will not really identify 60- or 120-Hz modulation, so
demodulating in AM and looking at the resultant audio is an important step.
>
> Ed
>
>
> ________________________________
> From: RFI <rfi-bounces+w1rfi=arrl.org@contesting.com> on behalf of Jim
Brown <jim@audiosystemsgroup.com>
> Sent: Monday, June 6, 2022 1:45 PM
> To: rfi@contesting.com <rfi@contesting.com>
> Subject: Re: [RFI] Power Line Radiated Interference Limits
>
> On 6/6/2022 4:28 AM, Hare, Ed, W1RFI wrote:
>> You can also make a .wav or .mp3 file and run it through a free program
called 'Audacity" and analyze that spectrum, with the understanding that
your receiver bandwidth is usually limited below 200 Hz or so, so that
120-Hz component may be reduced in amplitude.
> The best diagnostic tool, by far, to identify power line noise, as
> opposed to electronic noise, is a broadband WATERFALL of either a
> receiver's IF or RF. Powerline noise and lightning static is arcing, and
> will show up as horizontal lines on a slow waterfall.
>
> Electronic noise is the harmonics of square waves used in switch-mode
> power supplies and other power control electronics like variable-speed
> motor controllers, which show up as vertical humps of noise spaced at
> 10-50kHz, and microprocessor clocks, which sound like carriers and show
> up as narrow vertical lines.
>
> Power line and other impulse noise is present at all frequencies, but is
> best chased at the highest frequencies where it can be heard.
> Traditional techniques apply. Electronic noise must be chased on the
> frequencies where it is heard.
>
> More on this in this here.
> http://k9yc.com/KillingReceiveNoise.pdf and
> http://k9yc.com/KillingRXNoiseVisalia.pdf
>
> 73, Jim K9YC
> _______________________________________________
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> http://lists.contesting.com/mailman/listinfo/rfi
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> http://lists.contesting.com/mailman/listinfo/rfi



------------------------------

Message: 4
Date: Mon, 6 Jun 2022 21:14:53 -0500
From: Charles Plunk <af4o@twc.com>
To: "rfi@contesting.com" <rfi@contesting.com>
Subject: Re: [RFI] Power Line Radiated Interference Limits
Message-ID: <5bca0b93-8216-eb67-d2d8-a1dcc0aac8aa@twc.com>
Content-Type: text/plain; charset=UTF-8; format=flowed

Jim, I thought the same thing. That is my best lesson learned tracking 
power line rfi. Noise seems to be everywhere when out tracking in the 
field. Every pole has some around here near field. To be as sure of 
success as possible you must find some way to track the -correct- noise. 
No fun getting the util out and your findings be wrong.

I have been most successful (without spending high dollar on rfi gear) 
retransmitting the noise from my station receiver to a HT -especially- 
if I can catch it with a distinctive pattern. And comparing audibly with 
a tracking ht with handheld yagi and/or ultrasonic dish. Fortunately 
most of my power line rfi at some point will go intermittent with a 
distinctive pattern usually varying with humidity. Patience is key here.

Sorry for repeating as I know I have told this story in the past but it 
really made a huge difference in my ability to track down the right noise.

Many months now 120hz buzz free :-). Well some distant stuff but NB 
works fine.

73

Chuck
W4NBO


On 6/6/22 20:08, AA5CT wrote:
> Won't he be surprised when it DOESN'T cure the problem
>
> and any
> nearby sources located may not be the one creating all the havoc
> at the station QTH.
>
> de AA5CT Jim
>
>

------------------------------

Message: 5
Date: Mon, 6 Jun 2022 19:29:16 -0700
From: "Dave (NK7Z)" <dave@nk7z.net>
To: rfi@contesting.com
Subject: Re: [RFI] Power Line Radiated Interference Limits
Message-ID: <ae644d93-d2b0-f178-5142-0049ceae88de@nk7z.net>
Content-Type: text/plain; charset=UTF-8; format=flowed

Hi,
I have a three part article at:

https://www.nk7z.net/sdr-rfi-survey-p1/

which may assist you in quantifying the RFI...  It uses a SDR to show 
you your RFI in a few different ways.

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On 6/5/22 19:12, Riki, K7NJ wrote:
> I've recently become plagued by power line interference that is most
> noticeable on 80M and 160M.  In the past,, the local power company had
been
> cooperative in fixing the source(s) of such interference.  However it's
been
> about 7 or 8 years since I've been in touch with them about such issues.
> Just to be prepared, I would like to know what specific limits there are
on
> power line emissions (if any).  I know that in the past, the requirements
> were very lenient - only requiring power companies to follow good
> engineering practice without any quantitative emission limits.  In any
case,
> having the actual reference paragraph numbers in the FCC rules would be
most
> helpful. As I recall, this had been somewhere in Part 15. Any help would
be
> appreciated.
> 
> 73, Riki K7NJ
> 
> 
> 


------------------------------

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------------------------------

End of RFI Digest, Vol 233, Issue 5
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