I’m curious, how many people are aware of these sounds. I have designed, etched, and built my own switching power supplies along with winding my own transformers. I am aware of the source of the noise. So, does anyone else hear these high frequency sounds regularly?
47 here. Battery chargers for tools in the shop drive me insane. I used to work at a city run arena that had those hi pitched squeaky things to keep young people from gathering. I had to get transferred it was like torture.