I live in a town that has some pretty huge military radars (S- and X-band radars), and while they are pointed away from the population - the side lobes still se

I live in a town that has some pretty huge military radars (S- and X-band radars), and while they are pointed away from the population - the side lobes still send out a periodic chirp that has the duration of exactly 10.5 seconds, and it is only audible in audio equipment. And for guys like me, that operate a home recording studio, it really fucking sucks. Another place I lived, there was this 7 kHz noise that would also get on top of any amplified source - almost drove me insane, and could never figure out what it was. It was some kind of RFI. At first I thought it was something related to the house, maybe a bad ground combined with some switching circuit. Turned off the mains breaker, and hooked up my guitar to a battery amplifier - same annoying noise was present. Tried shielded cables, tried cables in different lengths from longest to a short 5 cm patch cable, still there. Went outside, and it was present. No distribution transformer, gas meters, or smart meters in general. Also, back in the day, we'd get Soviet TV coming in waves - meaning that you'd get some periodic interference where your TV would show a combination of both. I think it was due to their huge over-the-horizon radars. (But I've never had any problems with RFI from cars!)