Hi The crystal industry in the US went from a couple of outfits (mostly in PA) making < a hundred a month in the 1930’s, to a massive bunch of outfits during WWII. Most were turning out a couple hundred an hour.
Much of that collapsed when the war ended and the demand went away. A few outfits combined with others. The vast majority of companies simply vanished. Bob > On Feb 27, 2020, at 2:07 PM, jimlux <[email protected]> wrote: > > On 2/27/20 8:45 AM, Richard (Rick) Karlquist wrote: >> OTOH, you could build a simple Colpitts >> oscillator and see where it oscillates. >> That's what they did back in the dark >> ages. >> Any time nut should be up for that. >> Rick N6RK > > But does a deForest Audion (ref Colpitts patent 1624537 1918) have enough > gain at 5 or 10 MHz? > > I guess so, by 1930 deForest was selling oscillators and receivers at 15,000 > kilocycles. Although I didn't see any indication of crystal oscillators - > they're all LC tuned. (One mention of crystal control is in an article about > a SW crystal controlled Transmitter by Lester Spangenberg) > > https://www.americanradiohistory.com/Archive-Radio-News/30s/Radio-News-1930-05-R.pdf > > (Timenuts - your experience and training probably qualifies you for a job in > Radio-Television - Talking Pictures, see the ads!) > > I seem to recall that crystals for frequency control (on a commercial basis) > were sort of a post WW2 thing (partly because of developments in piezo > hydrophones for sonar) > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
