Vacuum tubes in power applications are still viable, and some of the vacuum tubes in Russian avionics were very miniature, about the size of a transistor (counting the encapsulating plastic) which does roughly the same thing as a vacuum tube.RSX11 wrote:Yep, the godless communists were using vacuum tubes in the Foxbat - but, our engineers speculated that much of the reason for that was the ability of vacuum tubes to shrug of the effects of an EMP from a nuclear blast, unlike the semiconductors of the time. As well, vacuum tube gear can handle extreme temperatures better, and, at the time, could handle vastly more power - that allowed the Foxbat to have a 600 kilowatt search radar. 600 KW is a lottta power....
It wasn't that long ago that virtually all computers had vacuum tubes. That thing you stared at, your CRT display? Yep, you were staring at a vacuum tube, right into the electron stream's muzzle.