[vacuum tube failures can be spectacular]
Hrm. In my experience they just went out like bad light bulbs.
But then again, all I've ever seen was radio tubes.
I DID get to see a modern radio-transmitting tube about 3 weeks ago. It was the size of a
lunch box. It wasn't a final tube though - I was told the AM final
tubes are about the size of my head. It had a metal jacket so you couldn't
see inside it, but it weighed a hefty amount. It went to some unknown FM
broadcast transmitter.
(One of our customers is a company that owns a few radio stations.)
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