Re: In a dim and distant past.
Excellent story! (unless you were there for the 3 hours, of course)
I use to be a TV engineer for Rediffusion in Norwich back in the 1970s. We never had that specific problem though we did have one particular customer who used to swap all the valves around in his set and then call us to put them back into the correct sockets. Being quite hardy things there was (mostly) no damage done to the valves.