Experience of geomagnetic field recording with a fluxgate magnetometer having a bridge sensor

A fluxgate magnetometer has been developed at the Geological Survey of Sweden. It measures the field in three orthogonal directions and has sensor elements forming bridges. The instrument can have direct readout in both digital and analogue form with a resolution of 0.1 nT.An instrument of this type has been adopted for stationary recording of geomagnetic elements in digital form. Special attention has been paid to insure good long term stability and high reliability. Experience from routine recording is described.