Chances are that audible noise is caused by a broken jumper when a
lightning arrestor where it attaches via a hotline clamp onto the line. I
think I've heard that sound about 20,000 times! Ed's point about standing
under the line, also known as line of fire, is always best to not be under
it regardless of the situation. And no one should bang on a pole or shake a
guy wire including employees of the utility. Doing that shares an extreme
lack of education or ignorance. I have often told people during my lectures
that knowing there's a 7000 volt arcing source over your head that you
should bang on what's doing it!
Mike Martin
RFI Services
240.508.3760
mike@rfiservices.com
www.rfiservices.com
On Mon, Oct 17, 2022, 8:22 AM Hare, Ed, W1RFI <w1rfi@arrl.org> wrote:
> If you can hear an arc or heavy spark taking place on a pole, that pole is
> certainly making a lot of RF noise! It really is also a maintenance issue
> because it is possible that the arc is eroding metal, possibly dropping a
> line to the ground.
>
> Utility people can use the "bang the pole" technique because they cone off
> the area, don't stand under the lines and wear hard hats. (Or they
> should!) Something is wrong on that pole and if you bang it, you may
> diagnose the problem by dropping the bad insulator through the windshield
> of the passing car. Leave that to the pros.
>
> Ed Hare, W1RFI
> ARRL Lab
>
> ________________________________
> From: RFI <rfi-bounces+w1rfi=arrl.org@contesting.com> on behalf of Don
> Kirk <wd8dsb@gmail.com>
> Sent: Sunday, October 16, 2022 9:01 PM
> To: RFI <rfi@contesting.com>
> Subject: [RFI] RFI case where I could actually hear the power pole arcing
> with my naked ear.
>
> Today I tracked down RFI to a power pole that was causing problems at
> N4TZ. This was an interesting case as the pole was located in front of a
> house out in the country and the homeowner saw me looking at the pole with
> my portable RF direction finding gear and she came out to talk with me and
> to apologize about her barking dog. The homeowner immediately mentioned
> that the pole makes a lot of noise and sure enough I could hear the arcing
> with my naked ear (you can hear it at the 2:30 mark in my video). She also
> mentioned that she recently saw an employee of the cable company
> banging/hitting the pole.
>
> Here is a link to a video I just uploaded to youtube documenting this case
> for those interested.
> https://youtu.be/TVjKANTmVEc
>
> 73,
> Don (wd8dsb)
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