Varicap VCO (CB870E)

This voltage controlled oscillator uses a varicap to change the frequency. Usin a 100 turns coil (28 to 30 AWG on a ferrite core) the circuit will produce signals of about 1 MHz. Any varicap can be used in this circuit and the signal can be picked from the transistor´s collector or by a loop on the coil.





Circuit Bench

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