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Nasty QRM - Video - What is this?

FatHam

FatHam

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Apr 15, 2011
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I'm hoping that someone will see this video and say "oh, that's probably ______"

What ever this nasty, pulsating interference is, it started a couple of weeks ago. At first I though it might be solar activity or something, but then realized that it happens day & night.

Lately I've spent most of my time on a local 2M repeater that comes in at 30 over, so it hasn't been noticeable. It's worse on HF than it is on VHF. If it's pulsing at an S9 and I'm talking to someone with an S7 signal, it takes them out each time it pulses. The other day, a friend about 50 miles away set up a 2M base and we tried to talk simplex. This "noise" was about an S6 and his signal was an S5, so it took him out.

What ever it is, it's not on my property. I shut down the power main to my house and the QRM is un-changed. Mole suggested possibly a fried street light, but it happens whether the lights are on or off. I drove around last night listening to in on 10M AM and of course it fades once I get a few hundred feet from my QTH.

There are overhead power lines in the neighborhood, as well as a pole top transformer behind my house that it could be coming from, but I have no idea how to track it down, or if I should be on the phone with the electric company because I "suspect" it's their equipment doing it.

Check out the meter in this video. It's bouncing up to almost 20 over on 6M. Does this look familiar to anyone? Any hints on tracking the source?

qrm - YouTube
 
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SmackDown said:
Have you tried calling the power company and placing a complaint? At the same time you can ask if the power lines are also transmitting data. (BPL) I think you can make a complaint through the FCC because it's interferring with your ability to rx.
3's
Click to expand...

I don't think I can call Edison until I've isolated the source(?). For all I know at this point, someone around me may have added a flashing neon light to their game room.

I'm hoping to find a way to hunt it down, rather than randomly knocking on doors or filing complaints.
 
AcidRod said:
I don't think I can call Edison until I've isolated the source(?). For all I know at this point, someone around me may have added a flashing neon light to their game room.

I'm hoping to find a way to hunt it down, rather than randomly knocking on doors or filing complaints.
Click to expand...

You dont have to track it down if you think it might be coming from your power lines or a transformer. I believe the power company is obligated to send out their noise guy if you call them. Tell them your a ham and describe the problem.

I did the very same thing when I lived in Indiana and they came out within a couple of days. There was a bad transformer behind my house which they replaced and solved the noise problem.
 
RatsoW8 said:
You dont have to track it down if you think it might be coming from your power lines or a transformer. I believe the power company is obligated to send out their noise guy if you call them. Tell them your a ham and describe the problem.

I did the very same thing when I lived in Indiana and they came out within a couple of days. There was a bad transformer behind my house which they replaced and solved the noise problem.
Click to expand...

Thanks, I may just fire off a call then.

Should have mentioned in the original post, that this goes away for 20-30 minutes from time to time. I'm not sure if a transformer would do that once it started to leak, but it could be that it quiets down when the load on the lines is reduced. Weird...
 
try to locate the source yourself before calling Power Co. They are busy and will appreciate your help. Some companies are very helpful, while others will be annoyed by your complaint.

i use a dual band HT with AM recieve with a built-in attenuator attached to a Arrow 7 element UHF yagi. Works like a champ. Most people blame transformers, however, they are rarely the culprit and will usually detonate when they have internal arcing. Most "powerline" noise is from loose/corroded hardware, bad grounds, cracked insulators and loose grounds.

Try to locate the pole or general vicinity of your noise if possible. makes it easier when the RFI guy comes out. he/she will use a directional beam to get a general location and then pinpoint the exact source with an ultrasonic locator or a hot stick with an RFI sniffer on the end.

main thing is to be very polite and keep very careful records of each conversation and work that they do. I worked with AEP for 3 years before I cleared up most of my noise. I live next to an industrial complex. They have spent thousands on upgrades and repairs around my shack. They still have a few sources to fix.

PowerLineNoise.com - Home

Track and Solve Electrical Interference

Power Line

EMI - RFI page
 
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BTW, since your picking that up on 6 meters, it is fairly close. I would say within 500 yards ( unless you have a high gain beam pointing in the direction of the noise). If you have a 2 meter rig with AM receive drive around until you hear it. Once you hear it on 2 meters you will be with a couple hundred feet of the source. make a little 2-3 element yagi to get the direction by nulling the signal.

have fun and good luck.

the first thing the power company will do is look at the noise signature on a scope. If it's not 60 cycle they'll say bye bye.
 
The more I listen...

It kinda sounds like a wired doorbell transformer going bad. It is definitely not BPL. The RFI inspector should also have a little handheld device that they place near the utility meter of houses around you that will identify inside sources of incidental radiators.

Good luck.
 
Thanks VERY much for taking the time... I'll look those links over tonight.

I don't have an Arrow Antenna or HT with AM, but I think I know someone that does <Mole -cough - hint>

Thanks again...
 
Just looked at the video Mark. Did you check the Forest Service Fire Station by your house? That has a very constant timing to it. Like a beacon going off. Just an idea? Maybe one of your neighbors has fallen and can't get up:laugh:
 
Crash Ash said:
Just looked at the video Mark. Did you check the Forest Service Fire Station by your house? That has a very constant timing to it. Like a beacon going off. Just an idea? Maybe one of your neighbors has fallen and can't get up:laugh:
Click to expand...

How long does it take for a Life Alert's battery to die? lol

No, this stops within a few hundred feet of my house. The Station's a good 1/2 mile.
 

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