Interference on LF
Any idea's what could be generating this QRM, i've had a snif around with my Malachite but cannot seem to locate a source.
I have a Airspy HF+ and YouLoop with laptop which I'm going to setup and power off the whole property to see if something I have is generating the QRM.
Almost certainly a switching power supply (wall wart et al) from the looks of it.
Subtracting two of the harmonics: 3.426 - 3.411 = ~15 kHz. So you'll probably find a huge RFI peak at 15 kHz on the Kiwi and maybe your other SDRs if they go that low.