Minimum Period of Electronic Oscillators

This paper considers the general problem of determining the conditions to achieve the minimum period of oscillation, regardless of wave shape, for simple electronic oscillators. In particular, emphasis is placed on the general minimum period problem for the tunnel-diode oscillator having a series inductiveresistive load. The minimum period of oscillation is established by varying the load's parameters. Various nonlinear analysis techniques show that the minimum period of oscillation is never obtained for a harmonic mode of oscillation. It is shown that the minimum period of oscillation is obtained by using no externally added inductance, and, for typical tunnel diodes, a load resistance approximately equal to zero. The results are confirmed by experiment. The conditions are also given for determining whether the tunnel diode will operate as a soft oscillator, hard oscillator, or be truly bistable.