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Series radio tuner

  1. Oct 4, 2009 #1
    How do you connect a variable capacitor to an inductor to make a series radio tuner?
    And where do you tap the resonant frequency to send to the RF amplifier?
  2. jcsd
  3. Oct 4, 2009 #2


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    Science Advisor

    Do you mean: how would you use a series tuned circuit to tune the input of a radio receiver?

    The series tuned circuit is able to give a very large voltage step-up if you have a low impedance source driving a high impedance load. The circuit has no power gain, so it converts a low voltage at high current to a higher voltage at a lower current.

    This depends for its success on the antenna and also it will depend on the frequency for a given antenna.

    I will attach a possible circuit. For the circuit to be of much use, I have shown a tapped inductor which may allow for the use of practical antennas.

    The series circuit, though, is just the inductor and the variable capacitor.

    Attached Files:

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