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JFET amplifier

  1. Oct 21, 2005 #1
    Does anyone know the purpose of the capacitors circled in red in the file attached? What are their functions in the circuit? Thanks!

    Attached Files:

  2. jcsd
  3. Oct 21, 2005 #2
    The capacitor allows the AC signal to pass, but blocks the DC bias voltage established by resistors so that any preceding circuit is not affected by it.
  4. Oct 21, 2005 #3


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    Staff: Mentor

    And the 4.7uF capacitor increases the gain above 66Hz. The source resistor in parallel with that cap is used to set the DC bias point more accurately.
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