Astable Oscillator experiment

Discussion in 'Feedback and Suggestions' started by Wendy, Apr 29, 2008.

  1. Wendy

    Thread Starter Moderator

    Mar 24, 2008
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    Someone was asking about this experiment...

    http://www.allaboutcircuits.com/vol_6/chpt_5/18.html

    I've never seen the configuration without base bias transistors, indeed the way I learned that circuit the base resistors were part of the RC oscillator equation. I may bread board it to test it myself, how sure are you of this configuration?
     
  2. Dave

    Retired Moderator

    Nov 17, 2003
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    It is not clear whether this is one of Dennis' or Tony's experiments. We've never had any questions about this experiment in past (that's not to say there isn't an issue). Perhaps you could breadboard it, Bill, and let us know if you observe any issues. If need be we can look at this circuit in a little more detail.

    Dave
     
  3. Wendy

    Thread Starter Moderator

    Mar 24, 2008
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    OK, I'll put another iron in the fire. :D
     
  4. hgmjr

    Moderator

    Jan 28, 2005
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    Bill,

    I too am more familiar with this astable oscillator having a couple of what I was taught to call base-return resistors.

    hgmjr
     
  5. beenthere

    Retired Moderator

    Apr 20, 2004
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    Agreed, there have to be resistors to supply base current. By the way, oscillators are astable by definition.
     
  6. hgmjr

    Moderator

    Jan 28, 2005
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    Good point. As you can tell I used to work for the Department of Redundancy's Redundancy Department.

    hgmjr
     
  7. Wendy

    Thread Starter Moderator

    Mar 24, 2008
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    If you read the experiments notes he mentions a bit of unstability with it oscillating, which isn't too suprising. I'm suprised it works at all, although thinking about it why not? Still 2 inverters coupled with caps and all that.
     
  8. beenthere

    Retired Moderator

    Apr 20, 2004
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    It's just a square wave oscillator.
     
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