Magnetic detector circuit

摘要

A magnetic detector circuit for determining the presence of a vehicle, which circuit has compensation means for eliminating the effects of magnetic fields which are caused by the operating currents of electric railways which pass by in the vicinity, the output signals of two identical detectors, which each have an excitation and an induction winding, are excited by an identical signal and are arranged at a spatial distance from one another, being subtracted from one another such that, in the case of a magnetic field which acts essentially identically on both detectors, the signal "zero" is produced as the subtracted output signal of the induction windings during the subsequent evaluation.