[SADXA] Help identifying this RFI

[Carl Foster]

That looks and sounds exactly like intermittent power line arcing. The power
lines will radiate the signal and make it nearly impossible to pinpoint. A
portable directional VHF antenna and receiver with an S-meter will probably
help locate the source. It is likely on a pole so pointing the directional
antenna at different poles should give an indication of which pole is
causing the problem.