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Homework Help: Signal Source - (Thévenin, Norton)

  1. Aug 27, 2006 #1
    I am troubled by this question. The book for this new course seems to have different terminology then what I am accustom to. I'm stuck on this question, because I don't understand what it is asking.

    question) A particular signal source produces an output voltage of [itex] 30\,mV [/itex] when loaded by a [itex] 100\,k\Omega [/itex] resistor and [itex] 10\,mV [/itex] when loaded by a [itex] 10\,k\Omega [/itex] resistor. Calculate the Thévenin voltage, Norton current, and source resistance.

    answer) not sure.

    my guess is that there is some signal source, say [itex] V_s [/itex] that is in series with a resistor, say [itex] R_s [/itex]. [itex] R_s [/itex] (which is the source resistance) is then connected in series to a load resistor, say [itex] R_L [/itex]. Where [itex] R_L [/itex] has the values [itex] R_L=\{100\,k\Omega, 10\,k\Omega \} [/itex].

    So when you load the signal source with these resistance values, an output of [itex] 30\, mV [/itex] and [itex] 10\, mV [/itex] is measured respectively.

    Where do I measure this voltage? Across just the signal source? Across the load? Across the resistor and signal source?

    Any help would be very appreciative.
    Last edited: Aug 27, 2006
  2. jcsd
  3. Aug 28, 2006 #2
    The measured voltage would be across the load RL.

    Also, the two measurements will give you the required two equations for solving the two unknowns (Vs and Rs).
  4. Aug 28, 2006 #3
    Thanks doodle!

    Pretty easy question then :)
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