Signal discriminator

A signal discriminator utilizing the variation of the dielectric constant of the MnZn ferrite. The discriminator has a capacitive reactance C. The complex dielectric constant of the capacitive reactance C varies with frequency, and the real part [epsilon]1 of the complex dielectric constant is large in the low-frequency band and small in the high-frequency band. The capacitive reactance C of the reactance component X2 is not ignorable with respect to the inductive reactance L. Therefore, the reactance X2 of the parallel circuit of the capacitive reactance C and the inductive reactance L is decreased, and the influence of the capacitive reactance C is decreased in the high-frequency band. As a result, the reactance component X2 is decreased with respect to the reactance component X1 of conventional soft magnetic materials. The X-R cross point frequency moves to the low-frequency side of the conventional X-R cross point frequency XR1. Consequently the noise in the frequency band where noise components are present is converted into thermal energy, and the waveform distortion caused by high-frequency noise can be reduced.