Hi > On Jul 2, 2020, at 2:34 PM, Hal Murray <hmur...@megapathdsl.net> wrote: > > >> Funny, just yesterday I was looking at the design of a laboratory cesium >> beam standard from 1963. Sorry, there's no divide-by-5 example in there. But >> the attached images show the 108x multiplier (8.5 MHz to 9180 MHz). Sure >> enough, spot the 12AX7 and 6J6 tubes in use... > > Neat. Thanks. > > Interesting. I'd expect transistors to be in use by 1963.
Some at low frequency, not a lot for high speed in production gear. A bit faster in terms of one of a kind lab devices. > > When did tubes die out? They have yet to die out ….. :) > > How fast were transistors back then? The typical germanium transistor of the day was lucky to have an Ft rated in MHz (yes a slight exaggeration) > How fast could you toggle a 12AX7? Depends on how fancy you wanted to get …. 10 MHz to 100 MHz. Bob > > Wikipedia says the first 7090 was installed Dec 1959. The core memory cycled > at 2 microseconds. > > Was 9180 MHz fast enough that it required a tube so it was simpler to use > tubes on the rest of the logic? > > -- > These are my opinions. I hate spam. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
