Now happily retired, I used to work for a world famous UK based broadcasting corporation, in TV outside broadcasts. Way back when we had live limited overs cricket on Sunday afternoons, we were happily well into the first innings when all the fans started rhythmically speeding up and slowing down and bulbs got brighter and dimmer. I glanced up at the incoming voltmeters which were swinging up and down like a fiddler's elbow. The AVRs on the input couldn't keep pace with the swings so there was only one thing for it. On a live, non repeatable broadcast I reached up and hit the breakers, turning off the technical supplies to the kit and removing cricket from thousands of tellies up and down the country. The dividing door between us engineers and the production gallery popped open and an inquisitive looking head poked through.
We explained if we hadn't done it we'd have lost the programme completely as every fuse would have blown whereas now, once we get to why it happened, enough kit will have survived to get something on air. many OBs are powered by a portable generator (think the size of a bin lorry) so our capo di capi went off to pass the time of day with the genny man. It turned out he had a minor problem with the stabilisation control system on the generator so though he'd use the time fault finding. He bypassed the system completely, then grabbed hold of the engine speed controller and started to give it a good workout. While the error of his ways were explained to him we'd been on our hands and knees, scrabbling around behind dusty bays replacing fuses. We lost about five minutes of airtime in total and came out quite well in the subsequent enquiry.