An experimental investigation into the operation of the parametric phase-locked oscillator

Basic principles of operation of the ¿phase-locked oscillator¿ are discussed. Measurements were carried out at low frequencies (5.5 Mc/s) in order to observe the relevant waveforms on a conventional oscilloscope. Abrupt junction diodes were employed as the variable reactance elements and balanced circuit configurations were used to reduce the amplitude of pump signal at the output terminals of the device. The time required for maximum build-up of oscillation is shown to be reduced by increasing (1) the pump voltage, (2) the phase-initiating voltage and (3) theQof the resonant circuit. The second circuit presented is shown to achieve a buildup time of approximately 6 cycles of output frequency and to be relatively independent of loading. Finally, the practical applications are briefly discussed including the use of the device for logical circuitry.