Wein bridge circuit

Discussion in 'General Electronics Chat' started by kvsingh21, Apr 22, 2009.

  1. kvsingh21

    Thread Starter Active Member

    Apr 15, 2008
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    Hello
    I am designing a wein bridge circuit, which should have output pk to pk 10V. Its fairly simple to control frequency of the circuit, but what components values contol the output votage? And is there any formula for calculating it?
    The schematic is shown here. LINK.
    Thanks in advance for your help.
     
  2. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
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    The ratio of R10 and R11 will be the primary determiner. The formula isn't going to be straightforward, because the forward feedback is somewhat variable. The back-to-back diodes form a rudimentary AGC loop to keep the output fairly linear.

    Eric
     
  3. kvsingh21

    Thread Starter Active Member

    Apr 15, 2008
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    Thanks.
    The output soine wave is not very good, any recommendation on how to improve it?
    Also is there any easy way to convert this into sine wave oscillator?
     
  4. Wendy

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    Mar 24, 2008
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  5. kvsingh21

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    Apr 15, 2008
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  6. Wendy

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    A 555 Schmitt Trigger?

    555 Schmitt Trigger


    A 555 Oscillator would make more sense, unless you are want a sine wave and a square wave.
     
    Last edited: Apr 23, 2009
  7. kvsingh21

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    Apr 15, 2008
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    Is there no way wein bridge arrangment can be used as square wave oscillator?
     
  8. Wendy

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    Why would you want to? The whole point is it is a reactive tuned circuit, which implies a pure signal (ie, sine wave). You could bump the gain of the transistor way up, but my understanding is frequency stability suffers, while there are already designs for square wave oscillators that are more stable and require fewer parts.
     
  9. kvsingh21

    Thread Starter Active Member

    Apr 15, 2008
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    Thanks for your help Bill.
     
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