Automatic Determination of Resonance in Oscillatory Circuits

A method for tuning oscillatory circuits is described. The method consists in feeding the oscillatory circuit with rectangular current pulses of linearly varying frequency, isolating circuit oscillations with phases of ±45° (these phases correspond to the cutoff frequencies of the circuit passband), and calculating the resonance frequency by using the symmetry of the oscillatory circuit characteristics. The device ensures the control of the passband, resonance frequency, and the equivalent quality factor of an oscillatory circuit in a wide frequency range (from 0.1 to 60 MHz).