A low component count RF Oscillator
simple RF oscillator provides good frequency stability because
capacitance variations at the semiconductor junctions are swamped out
by C1 and C2. The diode protects the transistor BE junction from
large reverse voltages and has a helpful effect on shaping the current
flow through that junction. The frequency of oscillation is set
by L1 and C3. The frequency limit of this circuit is about 10MHz.