Here is a simple discription of an oscillator by using just two Field Effect Transistors to generate frequencies up to VHF. Note that the 16pf feedback capacitor is the same for any frequency, so you do not need to change the value. All you have to do is to calculate L1 and Ca for the frequency you want to use!
If you want to use this oscillator as a VFO you must stabilise the supply Voltage with a 7809 or similar. The only peculiarity of this circuit is that the amplitude will vary with frequency. If you wish to use the circuit for an RF-generator then you will need to build a compensation circuit to make the output voltage more stable. For example, an AGC amplifier after buffering could be the ideal solution.
Return to INDEX page