[RFI] UPDATE re: Source power pole located - but wonder which components most likely temperature sensitive

[jimk8mr at aol.com]

 This is a posting from 2022 that I think is worth repeating. Those little noise sources can create big problems later, although this one fortunately was fixed before it became a really big problem. As noted, the list does not pass photos, but I'd be happy to send the photo to anyone interested.

73  -  Jim   K8MR
=================

Last Thursday night I sat down at 10:30 pm for my weekly effort in the Northern California Contest Club NS Sprint, a half hour contest for CW hotshots. Things were going good on 15 meters when at 10:35 pm a strong noise suddenly showed up at my usually relatively quiet suburban QTH. It raised my noise floor by about 20db from the usual on 15 and 20 meters, perhaps a bit less on 40 and 80 where atmospheric noise was more of a factor.



After the contest ended at 11 pm, I decided to do some quick checking. I drove down the street in the direction of the noise holding an HT out the window, and found a noisy spot about a quarter mile from my house. I then went back with on my bike (well lit, on a very lightly traveled street) with the HT and a 432 yagi. I found an area within a pole or two where the noise peaked. There was no visible arcing, so I went home for the night.


In the morning I repeated the trip on the bike, and then drove back with my W1TRC ultrasonic detector. I easily found the culprit pole. Then looking around, I noticed a broken side mounted insulator on the high voltage line, with that line laying across the service drops to four nearby houses.


I went home and called my RFI contact at First Energy, who was out of the office. But his voice mail message gave an 800 number to call in an emergency, which I did. Once I got the agent to understand that the problem was not at my house, she then wrote up a trouble ticket. By the time I came home from doing some projects at 5 pm, the issue had been repaired.


I don't have good measurements, but it seems that the noise in that direction is now somewhat less than it had been before. Had I been hearing low level leakage across a cracked insulator? That I may never know for sure.


I wonder what the chances were that I'd be on the air when that insulator broke? And if not for me, whether I caught it immediately or at some later time when chasing noise, how long would that high voltage power line have been laying across those low voltage lines? And what could have happened with that?


This list does not pass photos, but I'd be happy to send a photo of the bad pole to anyone interested.





    On Saturday, February 3, 2024 at 09:13:30 AM EST, Michael Martin <mike at rfiservices.com> wrote:  
 
 Charlie I'm sorry I don't have time to write I really thorough and long
response to your post. However, if you're purchasing and I are camera for
the use of Powerline noise you'll be wishing your money. It is not
economically feasible. I have been out with many infrared camera sales
people and Corona can people. I challenge them in a neighborhood that I
don't frequent and I tell them to find every Source they can find in the
neighborhood. I go out and I find every Power Line noise in the
neighborhood. We spend a couple of hours doing this and come back and
compare them. Rarely is there more than one source that are matching. Most
power line noises are created by very small sparks. It's unfortunate as
most amateur radio operators want to explain to the power companies that
these are all catastrophic failures and due to a lack of maintenance. That
is just not factual. The Sparks that create most of the power line noises
do not create Heat because of the lack of current flow. Most sources are
induced voltage into hardware near the primary conductor. As for ultrasound
it works wonderful however it's direct line of sight capabilities inhibit
finding a lot of the sources that are internal such as Lightning restors
Arc through insulation and conductors and things like that. I read most of
the input on this reflector and I wish I had time to comment on everything
but I don't. I spend just about every day locating Powerline noise for
power companies all over the country and I just can't find the time to
reply to post that I'd like to because I'm too busy finding noise. I use
ultrasound and RF every day I use the UE and the radar engineers. The radar
Engineers is the best piece of equipment out there and in no way should
anyone think they're going to find the average Source 200 ft away or even
60 ft away. The average power line noise from Hardware to ground is
typically no more than about 50 ft. On the average! I find over 90% of my
sources using ultrasound. Sometimes those sources are determined because I
can't receive it with ultrasound and that helps to point toward the source
as well as being able to hear it. And for red is not a good tool for
finding Powerline resources. My experience does not come from taking a
class and being certified. My experience comes from actually doing it and
time and time again finding the source a lot of times repairing it myself
to get a total understanding of why it happens as well as a lot of lab
reconstruction.
 Best wishes to everybody.

Michael Martin
RFI Services
51 W Bay Front Rd
Lothian, MD 20711

240-508-3760
mike at rfiservices.com
www.rfiservices.com