Thursday, November 10, 2011

Powerline noise issue

Despite the fact that I live pretty close to some power transmission lines as well as the regular above-ground residential service, I've been pretty lucky in that I've never had much of an issue with powerline noise. Unfortunately, that changed just about a week ago. It might be coincidence, but there there were about 4 or 5 houses around a block away from here that lost power due to the October snowstorm that didn't get it back until last Friday, which is when I started getting S7-S9 powerline noise on all the HF bands, 2m, and, to a lesser extent, 70cm. Given that there were still others in the area without any power (we were very fortunate in that we never lost power at our house), I figured I'd wait until the local power company indicated that they'd finished restoring power to everyone before calling to report it. (Powerline QRN is bad, but it doesn't come close to not having lights or heat.)  In the meantime, I put my main HF rig (Icom 756 Pro II) on a battery and turned off the main breaker to the house to eliminate any possibility that it was something in the house, but with that done, there was no change to the noise signature.

On Wednesday, the QRN was gone for a few hours in the middle of the day, and I figured that maybe they'd found and fixed the problem on their own, but it was back by the afternoon. Yesterday, the power company officially announced that all customers were back in service, so I figured that I'd give them a call today to see what they'd say.

The automated voice response system had no way to understand "RFI" so it thought I was reporting an outage, and because that's not the case, I finally got through to a human ... who seemed equally baffled. I explained that I was an amateur radio operator and that I was hearing electrical noise that I hadn't heard until about a week ago. He put me on hold for about 10 minutes and when he came out he said they'd be dispatching a crew.

While the recommendations for a situation like this are to try to narrow it down to a small area or even a single pole, in additional to not really having the right kind of DFing equipment for this, I'm home tending to one of my kids who is recovering from minor surgery, so I didn't want to spend the time walking or driving around. I am crossing my fingers that PSE&G (my power company) will take this seriously enough to send out a properly equipped crew and find the problem. I'll be keeping my fingers crossed.

Here's a short video that I took showing what the powerline noise looks like:

7 comments:

  1. Discharge noise from one of the poles - at that level, the pole could be upwards of 1 km away - get a cheap Sony belt-loop radio from Target or Walmart ($24) and start DFing -- or any radio that has a ferrite loop.

    Good luck!
    Colin - dxer.ca

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  2. Good afternoon Dave, I have 500KV transmission lines out the back of the house. I am very fortunate I have had no troubles. I have had some hissing in damp weather with the summer now and then but nothing like in your video. I would say the common denominator is the restoration from the storm. It could be a location that has a loose connection and or some type of arcing going on. The power company's power quality dept should be able to locate and repair the problem. As for dispatching a crew...I am a lineman and for the most part are not qualified to trouble shoot RFI troubles. The tools required and the expertise is just not there. Do keep us posted as to how it goes. I would encourage you to go to the higher ups at the power company as squeaky wheels gets the oil. Also see if there is anyway of finding out if any hams work there. There is a common bond there and an understanding also they my know who to see. Good luck and keep us posted.

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  3. Well, they opened a trouble ticket for me (technically they have it listed as an outage, which it isn't), and the status is available on their website. Every time I check, the message says "An outage has been reported and restoration is estimated to be by" where the time is about 8.5 hours from the time I look at it. I'm kind of hoping that they got the message that this was something that needed a specialized crew which I would of course expect to take a bit longer to get than a regular crew, hence the delay. But I do get your point about "squeaky wheel" and if nothing happens soon, I'll see if I can figure out who to contact there that might at least understand the problem and know what to do. FWIW, just in case someone out there reading this knows who it is, my power is from Public Service Electric & Gas (PSE&G) in NJ.

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  4. If you can Dave keep me updated with all that goes on at ve3wdm@hotmail.com I would be interested to see how it works out for you.

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  5. David,

    I had a similar issue this spring, all of a sudden I had horrible noise that sounded just like yours. I did the initial troubleshooting steps of turning off the breaker and going on battery and confirmed it was not in my house.

    I was also in a similar situation in that I didn't have a battery powered AM radio I could use to try to narrow down the area. Instead I just decided to give my utility a call (Idaho Power in my case) and see what happens. They opened a ticket for me, but at least in this case the agent on the phone understood the issue and sent it directly over to the Power Quality department.

    My wife noticed a power company truck driving around and stopping periodically around the house later that afternoon. The next day I got a call from a Power Quality Engineer, he said he did some preliminary searching and couldn't find anything, but wanted more details. That evening I e-mailed him sound recordings, as well as scope traces showing the waveform of the noise, band scope shots showing the repeating pattern, and a list of bands and frequencies where the noise was strongest. I got a call around lunch time the next day, he turned up the volume of a receiver he had in his truck, and confirmed he was hearing the same noise I was. It was, and though he said he couldn't detect it at my place, he was getting it very strong on his receiver about a block away.

    He said he had his normal DF equipment loaned out to another crew, and said it would be about a week before he could narrow it down. I was fine with this of course, I figured it would be a battle to get them to even look into it. He had another PQE from a neighboring town, who happened to be a ham himself, join him when he had his equipment back. They narrowed it down to a breaker on a pole feeding an underground run for a subdivision about 8 blocks away from my house.

    They advised me it could be a while because they'd have to schedule an extended outage to the entire subdivision to fix it. Again this was OK as it wasn't stopping all of my activities. Some nights it was worse than others, but most nights I could still find things to do on the air.

    About 2 weeks later I got home from work, turned on the radio and noticed that the noise was gone. Tuned all over and could hear no trace of it. I called him the next morning and left a voice mail thanking him for getting to it so quickly. I received a call back from him and he said the breaker actually failed at like 4:00 AM and caused an unexpected outage for a couple of hours. He was planning on driving out to verify the noise was gone before he called me to tell me. He said to keep his number and if I ever have trouble getting a ticked opened up for a power line noise, to contact him directly and he'd get it taken care of.

    There are lots of horror stories out there of long battles with power companies to even check into, let alone fix, PL noise issues. I just wanted to offer an example of the entirely opposite experience I had. My advice is once you get in touch with someone from Power Quality, be patient and understanding and they'll likely be happy to help you. If it's making noise and throwing off RF, that means something is wrong and has potential to cause further damage or an emergency off-hours outage down the line. In my case they were very grateful as it gave them the opportunity to try to fix it before it failed, even though they didn't get to it in time. Pass along detailed notes of what bands and even frequencies the noise appears to be the strongest, what time of day it is strongest, and as much data as you can give them.

    Please keep us updated on your situation, and I hope it is an easy fix for you.

    73 de KB7QOA
    Jeremy

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  6. Thanks for the interesting story Jeremy. I'm trying to be extra patient because even though the power to my area has been restored, I'm sure that they are still quite busy working on permanent fixes to what I'm sure were, at least in some places "quick fixes".

    What's interesting is that the ticket is still showing up with an expected resolution time of 8.5 hours from whenever I look; I assume that's just some automated function.

    Yesterday there was no noise at all, but I didn't have a chance to check before I left for work this morning. I'm also a little surprised that nobody has been in contact with me yet, but I figure that if (more likely, when) the noise returns, I'll try to politely get them to hook me up with the power quality folks.

    I will keep everyone posted as to the progress, thanks for your interest.

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  7. Lewis VE3QJ8:10 PM

    Thank you David for this fine article, it gives me an idea of how to deal with the noise around here. At best, i could work 20 meters but by 10: AM the noise on 80 was at least S9 or worse. I have a multi band radio with a ferrite antenna (a very large "venturer model 2559-2) which i can use. Perhaps i'll have that ghetto blaster on the shoulder look going down the street.
    Congratulations on a noise free ham shack :).
    73
    Lewis VE3QJ

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