Ring-core flux-gate magnetometers with self-saturating circuits

In the fundamental-frequency types of flux-gate magnetometer described in this paper, ordinary toroidal cores without air gap operate as field-sensitive elements in self-saturating push-pull circuits, as used in the magnetic amplifier art. The simplest form of such a magnetometer consists essentially of a half-wave bridge circuit, in which the two toroidal magnetic amplifier cores are replaced by the semicircular portions of a single ring core having two or four equally rated gate windings and acting as a flux detector. In a modified arrangement, two half-wave push-pull circuits with ring-core flux-gate elements are combined in a full-wave system, which may be utilized either as a very sensitive magnetometer or as a gradiometer for the measurement of the inhomogeneity of the magnetic fields.