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Re: [RFI] Power Line Noise @ N5OP

To: "'Kim Elmore'" <cw_de_n5op@sbcglobal.net>, <rfi@contesting.com>
Subject: Re: [RFI] Power Line Noise @ N5OP
From: "RFI Services' Mike Martin" <mike@rfiservices.com>
Reply-to: Mike@rfiservices.com
Date: Sat, 27 Feb 2010 07:54:08 -0500
List-post: <rfi@contesting.com">mailto:rfi@contesting.com>
Hello Kim,
I guess I miss understood your statement. I thought you were saying the
noise at the source was intermittent due to windy conditions but didn't
correlate to the starting and stopping of the noise at your home.

You are correct. The intermittency could be due to the wire , pole, or
hardware movement effecting the position of the sparking location. The spark
causing your issue could be in a gap as small as a thousandth of an inch. It
takes very little vibration to disturb this. 
The chance of being able to hear these noise sources with your ear is very
unlikely. This source isn't going to be corona, however the source may have
a component of corona as a result of the arcing. RF can travel a great
distances but corona will not.
Once you contact OG&E, send the person you're working with our emails. If
they don't want to communicate via email print them and hand them copies.
Let them know they are welcome to contact me, as they were trained by me and
a refresher over the phone sometimes goes a long way. They'll know this.
As for the intermittency, that is the result of their equipment and is an
issue they need to work with. It can be done and they know how to deal with
it. The important details are the direction and the band you receive it on
at your house. they'll need to have access to your antenna before and during
ever investigation. If you can't be present during the investigation have an
antenna connection available for them to tap onto. Make a run of RG 58 (with
the frequency labeled at the BNC connector) to the outside from your
antenna, that will allow them easy access and you won't have to be home. A
cable hanging by the meter is a good location if physically possible. This
will not alarm your neighbors because it's common to see the utility people
in this area.
If you suggest poles with noise sources on them, make sure it is your noise.
You don't need to fix them all, just the sources being heard by your
receiver. Because a noise source is close to your antenna doesn't mean it
will affect your reception. It is very common for me to find a complaint
source 2 miles from the complainant and I pass as many as twenty different
source along the way to the source that aren't effecting the complainant.
This is a very common mistake that adds to the expense and failure.
If you should end up with OEC all the above pertains to them as well. They
also have been trained. However you really should start with your provider,
especially if you believe the source is on their pole.

I spend hours every day answering emails and telephone calls from my clients
so it isn't always easy for me to respond to issues I see on the reflector
however I do my best to give support. So if it takes me a couple days to
respond and sometime I may not respond at all I apologize. My attention is
to my clients first and when time allows I enjoy doing what I can to assist
the amateur community, especially thru this reflector.

In the event you work with someone that isn't familiar with RFI services it
would be to their advantage and yours to recommend they visit my web site
and this reflector for information and education.

Mike Martin k3rfi
RFI Services
6469 Old Solomons Island Rd
Tracys Landing, Md 20779

-----Original Message-----
From: Kim Elmore [mailto:cw_de_n5op@sbcglobal.net] 
Sent: Friday, February 26, 2010 10:19 PM
To: Mike@rfiservices.com
Subject: RE: [RFI] Power Line Noise

I then went to your web sight and what I heard corresponds most 
closely to your audio example #3. The evening was dead calm while I 
was listening and the noise was steady. The noise is now gone.

Note that there seem to be two periods to the intermittent nature of 
the noise: a long period, on the order of hours, while the other is 
short period, on the order of a few  seconds. That may not have any 
significance, however.


Kim Elmore, N5OP

At 07:10 PM 2/26/2010, you wrote:
>This is your comment.
>The noise is intermittent: it starts and stops abruptly as the wind blows,
>though I can detect no obvious correlation to wind changes and the starting
>and stopping of the noise.
>Mike Martin
>RFI Services
>6469 Old Solomons Island Rd
>Tracys Landing, Md 20779
>-----Original Message-----
>From: Kimberly Elmore [mailto:cw_de_n5op@sbcglobal.net]
>Sent: Friday, February 26, 2010 12:29 PM
>To: Mike@rfiservices.com
>Subject: Re: [RFI] Power Line Noise
>Hi Mike,
>Thanks for your comment. I'm curious as to what it is about my
>investigations makes you suspect that I have identified the wrong noise
>source? It does match (roughly) the sound I hear at my QTH, about 0.5 mi
>away form the pole I identified. And, the noise starts and stops abruptly
>my QTH as well (something I failed to state explicitly).
>I will try to record a wave file of the noise when I hear it next. If
>successful, I will record it at 160, 80, and 40 m in 6 kHz AM bandwidth,
>2.7 kHz bandwidth, and CW 400 Hz bandwidth. What other characteristics
>be helpful?
>Kim Elmore, N5OP
>----- Original Message ----
>From: RFI Services' Mike Martin <mike@rfiservices.com>
>To: rfi@contesting.com
>Sent: Thu, February 25, 2010 5:55:59 PM
>Subject: Re: [RFI] Power Line Noise
>Your comment below suggests the source of you RFI isn't the source you
>The noise is intermittent: it starts and stops abruptly as the wind blows,
>though I can detect no obvious correlation to wind changes and the starting
>and stopping of the noise.
>If the noise on the pole has different characteristics than the source at
>your QTH you will be wasting effort and the opportunity with OEC. It's very
>important to be sure that you are sending them to the right noise.
>Since OG&E is your power provider it would be a good idea to start with
>them. They have several competent RFI investigators and should do great
>determining the source. If you can get a wav file of the noise send it to
>I have Bcc'd OGE.
>Best wishes,
>Mike Martin
>RFI Services
>6469 Old Solomons Island Rd
>Tracys Landing, Md 20779
>-----Original Message-----
>From: rfi-bounces@contesting.com [mailto:rfi-bounces@contesting.com] On
>Behalf Of Kimberly Elmore
>Sent: Thursday, February 25, 2010 4:01 PM
>To: rfi@contesting.com
>Subject: [RFI] Power Line Noise
>K3LR suggested that I submit this here because there are a lot of you that
>know a lot more about this than I do. So, here goes:
>Recently, I've noticed some pretty severe, intermittent power linenoise at
>my QTH. It had previously been a marvelously quiet place for
>radio, but over the past month or two, that has changed. I had it againthis
>morning and so decided to do some sleuthing.
>I live E of Norman, OK, in the center of a section bordered by Robinson on
>the S side, 48th St on the W side, Rock Creek Rd on the N side and 60th St
>on the E side.
>Both OG&E and OEC lines run down all roads. On Robinson (the S
>side) the OG&E lines are on the S isde and the OEC lines are on the
>N side. The OG&E lines run 35 kV -- I don't know what the OEC lines run. My
>neighborhood is served by OG&E and all wiring is under ground; step down
>transformers are above ground on concrete pads.
>Here are the details:
>I cannot detect the noise on any band above 40 m, but it's clearly apparent
>on 40, 80 and 160 m. My Orion II noise blankers are ineffective on 40 m
>(both the software and hardware noise blankers) but are very effective on
>and 160 m. Because I cannot hear it above 7 MHz, I'm pretty sure that the
>source is not emanating from a neighbor's house or from a nearby step-down
>Using my K9AY loops, I can detect the noise when the loops favor either NE
>or SE, but not whenthey favor NW or SW. Thus, the source is either to my N
>or my E.
>Using my 2 el 40 m beam, I found sharp nulls with the beam pointed either
>Nor S (probably nulls off of the sides), and less noise when the beam is
>pointed W than when it is pointed E (~S9+25 dB pointed E, ~S9+15 dB pointed
>W). So, F/B ratio favors a source to my E.
>I then got in my car, tuned my mobile rig to a quiet frequency in the
>aviation band (118.0 MHz) so that I could use the AM detector at VHF and
>started driving E along Robinson to 60th street. I heard nothing of
>substance along Robinson. I turned N and drove along 60th and found a
>strong noise source. I double checked my traverse and found the same spot
>three different times. It was considerably weaker from across the road than
>it is next to the pole. There is a private drive going E from 60th street,
>away from the offending pole. Driving down it 100 feet diminishes the
>strength significantly. The ground wire for the pole appears intact at the
>base.  I am absolutely positive that I have identified the pole holding the
>faulty hardware. I could see nothing obviously loose, but the culprit is
>most certainly there.
>The noise is intermittent: it starts and stops abruptly as the wind
>blows,though I can detect no obvious correlation to wind changes and the
>starting and stopping of the noise.
>What now? Whom do I contact with my information?
>Kim Elmore, N5OP
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