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Can anyone recognise qrm in attached picture?

Signals are spaced around 40khz.

It shows up randomly, no specific time patern so its hard to pinpoint the source.

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I had something similar.? Turned out to be the battery charger in next-doors RV.??

I see this with our house indoor ceiling fans. ?they all have motor speed controllers that generate lots of RFI..;-( ?plus... being in an HOA where the homes are smaller and closer... lots of people have solar panels / controller AND those darn decorative outdoor LED's on their houses... so lots of RFI ... but 40 kHz spacing is most likely a speed controller

Thank you for reply, now to figure out where is it ? it will be hard since it shows once in a while and it lasts 3-5 minutes

I tracked it down with a portable radio with shortwave with a signal level indicator (a must).? It was not easy since the RFI was coupled into the power lines and shrewd up many houses away.? The power lines acted as great complex antenna that masked the direction of the source.

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If your problem is from a charger it may be turning on for short periods to top up a battery.?