Adaption circuit for magnetic field probes with direct time coding

摘要

The invention relates to an adaption circuit for magnetic field probes for evaluating magnetic direct and alternating fields in accordance with magnitude and direction. The magnetic field probe exhibits a magnetisable core which carries a premagnetisation winding and an induction winding. An output signal is formed as measurement value for the magnetic field in time-coded form via a subsequent differentiating stage. To prevent the measurement value from becoming falsified by internal and external stray fields and errors in the conversion into the pure time-discrete measurement signal, the transmission range of the differentiating stage is limited, one limit being in the area of the fundamental frequency of the auxiliary alternating current and the other limit suppressing superimposed noise and interference voltages. <IMAGE>