50+,

Yeah, me too. Could swear that there were times my hair started to tingle. Audible line hum is usually there, but more evident in damp OR very dry conditions, IME...

Cross country lines are AC at some frequency to improve transmission of power, I think. Same as the very high voltage is used to reduce losses... (Or am I talking bosh? - I don't know much about these lines, and would welcome any corrections needed.)

HOWEVER, as has been mentioned, sweeping our metal lines in a repeating circle can become a very effective receiving antenna, in an alternating electromagnetic field. ...Even damp non-metal lines, apparently, can cause this effect...

WE have to show respect to the possibilities, THEY are simple, specific conditions, with no sense of civic responsibility, political correctness, or sympathy. They just do what they do, so don't get in the way.