Magnetometer operated at a self-resonant frequency by a sense winding

摘要

A self-resonant magnetometer using the inductance and interwinding capacitance of a sense winding to establish the frequency of operation. A sense winding signal is amplified to provide a driver current for a driver winding. The driver winding current with the addition of a dc offset current causes the mu (permeability) of a ferrite core to vary in a non-linear region of its B/H curve. The change in the mu of the ferrite core produces a change in flux in the magnetic core if an external magnetic field is present. This change in flux induces a signal in the sense winding.