Making an FM Transmitter

Discussion in 'The Projects Forum' started by vincent19-mas, Dec 1, 2013.

  1. vincent19-mas

    Thread Starter Member

    Dec 27, 2012
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    Last edited: Dec 1, 2013
  2. MrChips

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    Last edited: Dec 1, 2013
  3. vincent19-mas

    Thread Starter Member

    Dec 27, 2012
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  4. Dodgydave

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    Jun 22, 2012
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    If you read the page ....

    (MIC) converts the natural sound signal into the electrical signal. The capacitor C2 is coupled to the base of transistor Q1- S9018 and whenever there is signal from the microphone, the junction capacitance of the transistor changes that contributes to change in oscillation frequency.

    Resistor R1(2.2K) is a microphone MIC bias point resistance, usually value between 2K-5. 6K is preferred, R2 provides biasing to the base of transistor. C4 and inductor L (5.5 turns coil) make up the oscillator tuning circuit, you can change the value of C4 and L to change the transmission frequency.



    Formula for frequency calculation
     
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