Absolute Measurement of Declination (D) by Means of a Proton Magnetometer

摘要

A compensation method using stationary coils to measure declination (D) is outlined. In a large coil with vertical axis the current is adjusted so that Z = 0. A smaller coil with four sets of cylindrical turns is placed with its axis horizontal. This D-coil is provided with a telescope pointing at a mark nearly in the magnetic meridian. A proton magnetometer sensor is placed in the common center of the coils. Two series of readings are taken with the D-coil in erect and inverted position respectively. Variations of D, H, F and D-coil current are recorded. A simple formula gives the mean value of D.