Unkown signal

[Doodlebug]

On the 80 ham band I found this signal this afternoon, between two ham transmissions as you can see on my SDR. ( SDRplay running SDR console) with mag loop in field away from houses.

It's over 20kHz in bandwidth and makes a variable buzz if tuned in.
Anyone know what is it?  It lasted some 20 minutes.


   

[Murphyv310]

Hi Albert.
These seem to pop up anywhere.
I've seen them on my set up which just about parallels yours. Also a very odd sound on AM.
No idea what it is.