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Homework Help: Common-Emitter Amplifiers

  1. Sep 23, 2008 #1
    Quick question, i have a formula for finding rc (the ac resistance in the collector circuit) which is rc=RC(collector) is the parallel combination of RL I don't understand that for the example they have RC(collector resistor)= 12K ohms parallel to RL=50k ohms = 9.68K ohms.. someone explain the proper way to get 9.68k???? Thanks
  2. jcsd
  3. Sep 24, 2008 #2


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    Resistors in parallel add this way:

    [tex]\left( 50k^{-1} + 12k^{-1} \right)^{-1} = 9.68k[/tex]

    - Warren
  4. Sep 24, 2008 #3
    yeah I figured it out, just had never seen it in those terms, thanks warren!
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