Yes Don you are absolutely correct.
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On Dec 5, 2019, 1:24 AM, at 1:24 AM, Don Kirk <wd8dsb@gmail.com> wrote:
>Hi Michael,
>
>You mentioned three discharges per half cycle, but looks like it would
>be
>three discharges every other half cycle (if it is indeed power line
>equipment) since the period between the groups of 3 is around 16.7ms,
>not
>8.3 ms.
>
>Don (wd8dsb)
>
>On Wed, Dec 4, 2019 at 7:19 PM Michael Martin <mike@rfiservices.com>
>wrote:
>
>> your noise is caused by loose hardware on the power line equipment.
>> the three spikes you see per group represent three discharges per
>half
>> cycle
>>
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>>
>> On Dec 4, 2019, 5:07 PM, at 5:07 PM, David Eckhardt
><davearea51a@gmail.com>
>> wrote:
>> >I give up. It's power line discharge.
>> >Dave - WØLEV
>> >
>> >On Wed, Dec 4, 2019 at 11:24 PM Michael Morgan <michael@aa5sh.com>
>> >wrote:
>> >
>> >> I was hoping to get some help identifying a potential source for
>some
>> >RFI
>> >> that started a few weeks ago. I posted some pictures and audio
>clips
>> >from
>> >> 20 and 40 meters on my webpage. Thought it may be easiest there I
>> >hope it
>> >> is ok. https://www.aa5sh.com/?p=328
>> >>
>> >> I tried to get some screenshots from my 7610. On 20M the Noise
>> >Blanker
>> >> does a decent job of removing the noise but on 40M it is a bit
>two
>> >random.
>> >>
>> >> I have tried turning the main breaker off to my house and use a
>> >portable
>> >> radio (Recent RS-918) off a battery and the noise is still there.
>I
>> >did
>> >> walk around my property and noticed no real differences. The odd
>> >thing is
>> >> it's kind of random. It has been going to 30 Mins or so and it
>just
>> >> stopped for a minute while I've been typing this email for a
>minute
>> >or so
>> >> then started back up.
>> >>
>> >> Then at lunch today I took a break and remoted home since I saw
>where
>> >10M
>> >> was open and there was no noise for that 30-40 minutes.
>> >>
>> >> I appreciate any guidance you can provide. In my years of radio
>> >anytime I
>> >> have had noise problems I have always been able to narrow it down
>to
>> >> wall-wart or battery charger.
>> >>
>> >> 73
>> >>
>> >> Michael, AA5SH
>> >> _______________________________________________
>> >> RFI mailing list
>> >> RFI@contesting.com
>> >> http://lists.contesting.com/mailman/listinfo/rfi
>> >>
>> >One very last try: Copy to Word. Eliminate image. Copy test with
>no
>> >image. Paste to email. If this doesn't work, I give up:
>> >
>> >In your third image, the audio spectrum, the groups (first peak of
>> >first
>> >group to first peak of next group) is 17.5 ms.
>> >
>> >
>> >
>> >The period on one cycle at 60 Hz is 16.67 ms. Very close. The
>sound
>> >clip
>> >also sounds suspiciously like 60 Hz discharge from the power
>> >distribution
>> >somewhere in your vicinity. I usually detect this at 120 Hz as the
>> >discharge occurs at both the + and - peaks of the sine wave. But
>not
>> >in
>> >this case. In the time domain, I also usually detect an
>exponentially
>> >decaying envelope for each discharge. No so in this case. But,
>> >considering the period and sound, I'd guess its due to power
>> >distribution
>> >discharge in you area. Walk the power lines with your
>battery-powered
>> >radio. When you find a pole that is particularly, kick the pole
>hard
>> >and
>> >observe any change in the character of the sound on your radio. If
>no
>> >change, its not at that pole. Continue searching. Also, damp
>weather
>> >usually exacerbates the discharges as does dusty conditions.
>> >
>> >
>> >
>> >Dave - WØLEV
>> >
>> >
>> >--
>> >
>> >*Dave - WØLEV*
>> >*Just Let Darwin Work*
>> >*Just Think*
>> >_______________________________________________
>> >RFI mailing list
>> >RFI@contesting.com
>> >http://lists.contesting.com/mailman/listinfo/rfi
>> _______________________________________________
>> RFI mailing list
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>>
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