Magnetic field detector - consists of two equal coils with weak iron cores in series resonant circuit whose resonant frequency is close to that of input frequency generator, and outer premagnetising coil.

摘要

The voltage detecting circuit (9,10) consisting of a diode and smoothing capacitor determines the voltage lying at the inductance coils (3,5) of the series resonant circuit (2,3,5). The coils (3,5) consists of two identical cross-connected and spatially decoupled coils with soft iron cores (4,6). The resonant frequency of the circuit lies near to the frequency applied by the frequency generator (1). A pre-magnetising coil (7) is wound around the two coils (4,6), and is fed with a premagnetising current. ADVANTAGE - Circuit is simple to adjust and for exact measurement no additional compensation and amplification circuits, as for semiconductor Hall sensors, are needed.