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Homework Help: Transistor Question

  1. May 8, 2008 #1
    Sorry i couldnt get a copy and paste of the question, but it is as followed on the link:


    Question 3 on the electronics section, page 13.

    I got no ideas how to solve this. I wouldve assumed that there would be a DC compenant to the answer of this question but apparently there isnt. Please help
  2. jcsd
  3. May 8, 2008 #2


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    The capacitor C_out will filter out any DC component.

    I would first find the waveform at point 3. Then, to find the output, treat the capacitor as an ideal high-pass filter that passes the AC waveform but not the DC.

    Hopefully you were able to do question #'s 1 and 2 already. I find those helped my brain to "get into the flow" before I was able to think about #3.
  4. Aug 19, 2008 #3
    Another suggestion, you can try to divide this circuit into DC mode and AC mode.
    In AC mode, for example, Cin is regarded as short connection. So Vin connects to the base of transistor directly.

    To answer Question 3, you only need AC mode analysis.
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