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Simple AM Transmitter

  1. Nov 4, 2011 #1
    I have read that you can make a very simple AM transmitter using only a crystal oscillator like the one described here: http://www.sciencebuddies.org/science-fair-projects/project_ideas/Elec_p024.shtml" [Broken] I also read that you can make the equivalent of a crystal oscillator using a simple RLC circuit. Does anyone know if the attached schematic will work? I also read that the frequency of the AM wave will be (LCo)-1/2 as long as C1 >> Co and R < 100 ohms. Does this sound right?

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  2. jcsd
  3. Nov 5, 2011 #2


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    The circuit in your link does work, but it gives distorted sound, apparently. This is due to the severe mismatch on the transformer. This circuit is brought here occasionally with the comment that it either doesn't work or is distorted.

    Crystal oscillators usually use a 5 volt supply, so giving them 6 volts may damage them. This would depend on the resistance of the transformer secondary winding.

    The circuit you gave has no active components unless you have something at the port marked "input" that might oscillate. Active components are transistors, FETs Integrated ciruits etc.

    As it stands, no, it won't oscillate.
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