Simple high efficiency Colpitts oscillator .In the higher frequency ranges, above 50 MHz, Colpitts oscillators are used because stray circuit capacitance will be in parallel with desired feedback capacitance and not cause undesirable spurious resonances that might occur with the tapped coil Hartley design.
The FM VCO shown is a grounded base design with feedback from collector to emitter. A Colpitts oscillator is one of a number of designs for electronic oscillator circuits using the combination of an inductance with a capacitor for frequency determination.As you can see in the circuit diagram , this electronic project require few electronic parts an provide a 50 MHz-300MHz VCO with a tuning range of 2:1 .
