The AM Forum

I have enjoyed a pretty RFI free existence at this QTH until about 10 days ago when something showed up. I have never seen or heard anything like it and it does not seem to be coming from the home. Attempts to locate it with a portable have been unsuccessful. I have attached a .wav file and screenshot of what it looks like at about 1600 KHZ where it is really bad. The waveform on the screenshot is unusual.

Main Rig- Flex 5000 w/ 260' center-fed longwire.
Small town, 1-acre lot urban, but not dense
Prior to this little QRN
No HV transmission lines

Symptoms:
Nighttime only. Gone in the morning. However, during the day I think I can hear a faint whine I do not remember noticing before.
Wipes out BC to about 5 MHZ
NB on Flex will pretty much kills it except on BC band. There stations are readable but noisy. Boatanchors choke on it.
Walked neighborhood with portable rcvr. could not find a peak.

There was an article that the town was going to convert to LED streetlights, but I did not think that was until  the summer. Don't know if this is it.

Any thoughts?

Hello Carl, I would bet my next to last dollar that the sound RFI that you are hearing is a street light starter circuit. I had the exact same sound from one about 1/2 mile from me. In my case it would come on and increase with intensity and suddenly stop. A short time later it would start up again and start the process all over again. It was just a few months ago and it was cold outside and I didn't want to look for it.One night I spotted a lamp trying to start up and thought I'd better call the town electrician but someone beat me to it. Most of the time its a bad bulb and not the starter. I looked at Google maps and I see one right down the street from you and there are others down by that bay or whatever that area is?

Good luck.. 


https://www.youtube.com/watch?v=7ZX_eJeQLUc (https://www.youtube.com/watch?v=7ZX_eJeQLUc)

I had one of those blinky streetlights on my street down just 2 houses. A real mess on 160, 80 and 40M. To be fair the horrible noise did cause me to investigate noise cancellation by phasing a noise antenna. A fun project and article for Electric Radio came out of it!

Finally I spotted the offender visually. Dim Purple arcing. So I sent off an email to the power company. One morning on the way home from work I saw a power guy in his bucket changing a lamp on the very end of the street. I stopped and yelled up - thanks! Did you get my email about the one 4 poles down? He says No , I just spotted this one on the main road. But he came down and changed it pronto! and noise Gonzo. Whole life better. And it was just an accident that I spotted him.

Thank you, I really appreciate the feedback.
Interestingly, it was 100% gone last night.
I'll keep a log of it and when it shows again, I'll take a local walk.

W2UD, what issue is your circuit in?

Appreciate the feedback. It confirms my initial thoughts. I'll keep you posted.

Stay safe
73 Carl