I've heard those called 'pencil tubes'; the ones in hybrid walkie-talkies (for the transmitter) didn't get replaced with semiconductors until mid-to-late seventies. Nuvistors were ceramic-metal base, metal envelope tubes, very rugged, and much less microphonic than other vacuum tubes. There was a long period when they were the best fast-slewing amplifiers around, and for HV handling (like electrostatic deflection in CRTs) very hard to replace with silicon.
I dont' think anything much new got released after a certain point. But those tubes did offer the chance to make equipment smaller, and certainly in the early days of transistors, the tubes had better high frequency response. I had one of those hybrid lunch box walkie talkies, never used it, and if I recall properly the transmitter was all tube, the receiver had a diode mixer (no rf stage ahead of it) and a tube oscillator and multiplier chain, with the transistors in the IF strip and audio.
But by the end of the sixties, you could get Motorola handie talkies like the HT-200, which were all solid state. Hearing aids must have made the transition to transistors by then, and you could get portable radios that used transistors.
But at the time, top end test equipment wasn't as well known to the hobbyist. It was only later that I learned the Tek 454? (the mostly solid state one, not the one from 1959 with the plugins) used nuvistors.
Michael
They didn't have any transistors in WW2 - but they needed a crude doppler radar for proximity shells that could be fired out of an anti-aircraft gun.
AFAIK: they used what were basically ruggedised hearing aid valves potted in wax to stop them bouncing about.
Yup, I have a drawer full of unused/new :)
Jamie
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