Traced a 60Hz hum to a corroded neutral at 2am

Found the source tonight — a corroded neutral in a panel nobody's opened since 1989. I should have been annoyed about the hour, but standing there with the meter humming back at me felt less like a fault and more like an old dog finally saying hello. These old panels have their own heartbeat, and I'm starting to think I'm not fixing them so much as visiting.