Noise on 20m.

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  • Updated 4 weeks ago
Hi, What can be the origin of this type of noise on 20m.
This is a screenshot taken two hours after local sunset.
Left and right of the FT8 signals and up to S9 and seem to shift up an down the band.
Terrible if it gets on top of the FT8 signals.

Eddy ON5UQ.

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Posted 1 month ago

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Joe Conover

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Has be The Russians lmao
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Bob Craig, K8RC

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I've seen similar from a variable speed motor drive in an HVAC air handler.
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Ray Sylvester

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looks like a solar panel inverter
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Craig Williams

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Looks just like what I am getting in my shack. It's on more than 20 meters for me. I think it is coming from my router or modem. Need to shut down everything, put my SDRPlay on a laptop and chase it down.
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Jim Gilliam

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Does this noise repeat itself every 50 to 100 kHz? If it does, it is more than likely from some type of electronic switching device.
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Thanks for your reply.
I get terrible noise from a solar panel installation in my neighbourhood but only during daylight hours.
This noise disappears as soon as it is dark but the noise of the screenshot remains all night.
Is it possbile that string inverters or optimisers on each solar panel cause this RF noise during night hours ?

Eddy ON5UQ.