Regions of excitation of oscillations in a loop with discontinuous capacitance modulation

Relations for the limits of the regions of excitation of oscillations in a loop with discontinuous modulation of the capacitance are describied; the relations are obtained on the basis of analysis of the stability of the solution of the corresponding Hill equation. It is shown that the excitation zones may be divided into discrete regions; the number of these regions does not exceed the number of zones and depends on the parameters of the modulating perturbation. Results are given of an experimental investigation of the excitation of a parametric loop with rectangular videopulse pumping, with a depth of capacitance modulation varying within the range 0$\div$0.6.