Hi Mike and Gang,
Contrary to what I was told this morning the RFI has been eliminated and
the ground wire was indeed the cause of the RFI. It was arcing to
something up high on the pole and the supervisor that first came out this
morning did go up in a small bucket truck and was able to push on the
ground wire to stop it from arcing, and now has scheduled a lineman to come
out for a permanent fix. The noise floor at N4TZ dropped 6 S units on 10
meters from S6.5 as shown in the video to S0.5 when the ground wire was
moved to stop the arcing.
I went back to the pole this afternoon to confirm the power pole is no
longer generating RFI.
Just FYI,
Don wd8dsb
On Mon, Oct 17, 2022 at 10:56 AM Don Kirk <wd8dsb@gmail.com> wrote:
> Hi Mike,
>
> Points well taken, and thanks for your comments about the audible noise
> and possible root cause of it.
>
> I’ve been told the power company already responded this morning and
> noticed the ground wire that was moving around in the wind and they fixed
> that but that did not fix the problem. They are sending a lineman out this
> afternoon to dig into the problem.
>
> Just FYI,
> Don wd8dsb
>
>
>
> On Mon, Oct 17, 2022 at 10:30 AM Michael Martin <mike@rfiservices.com>
> wrote:
>
>> 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)
>>> _______________________________________________
>>> RFI mailing list
>>> RFI@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/rfi
>>> _______________________________________________
>>> RFI mailing list
>>> RFI@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/rfi
>>>
>>
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