Nonresonant inputs to a self-excited oscillator with a hard lif1it cycle

The oscillation spectrum of a self-excited oscillator with a "hard" limit cycle under nonresonant parametric or power input of a harmonic signal is calculated theoretically with certain simplifying assumptions. The variation of the spectrum in response to variation of the input frequency outside of multiple-locking bands is considered. It is shown that the locking mode is established in re­ sponse to multiple inputs only by drawing of the oscillator's frequency, without damping of the self-oscillations. An experiment performed in the radio-frequency band with input multiplicities n = 2 and n = 4 shows good qualitative agreement with the theoretical conclusions.