how a oscillator crystals were made

Discussion in 'General Electronics Chat' started by kubeek, Sep 14, 2016.

  1. kubeek

    Thread Starter AAC Fanatic!

    Sep 20, 2005
    A very insteresting old documentary from 1943
    They sure don´t make them now like they used to :D
    boatsman, djsfantasi, absf and 4 others like this.
  2. schmitt trigger

    Active Member

    Jul 12, 2010
    The difference is that they are all made in China now
    nsaspook likes this.
  3. nsaspook

    AAC Fanatic!

    Aug 27, 2009
    With the same lack of personal protection & safety equipment seen on the 1943 film.
  4. atferrari

    AAC Fanatic!

    Jan 6, 2004
    So manual intensive! Enjoyed it!

    Thanks for sharing.
  5. ronv

    AAC Fanatic!

    Nov 12, 2008
    Brought back memories of making figure 8's on a plate to get the frequency just right.:)
    atferrari likes this.
  6. be80be

    Senior Member

    Jul 5, 2008
    Thanks for the video
  7. boatsman

    Senior Member

    Jan 17, 2008
    Fascinating, thank you kubeek.
  8. Threeneurons

    New Member

    Jul 12, 2016
    I'd have to dig up some more videos. I didn't look at the video, but they use to mine the quartz crystals. I think Brazil was the big source for the raw stones. The process, was indeed labor intensive. Some time in the late 50's to early 60's they started growing the quartz ingots, much the same way the they process germanium and silicon ingots. Then at least the orientation of the quartz lattice was preset in the ingot. This was one of many process changes that led to the reduction in cost of making crystals.

    I still remember, in the 80s, that crystals where not all that cheap. In under 100 quantities, they still cost several dollars each. Though you could get a custom frequency part made, for under $20, in ones-n-two-zees quantities. Prices really started to fall until the rise of computers in everybody's house. Ceramic resonantors use to be a low cost alternative, if the frequency didn't need to be too precise. Lately, I've found lots of sources for crystals costing only a few dimes, in low quantities.