Compensation system for a magnetic compass

摘要

In a vehicle locating apparatus that utilizes Hall effect generators to determine the magnetic heading of the vehicle there is provided magnetic compensation by the placing of a coil around the Hall generators. A current source generator provides power to the coil of such magnitude so as to create a magnetic field which cancels the spurious local magnetic field components. The system includes a set of manual switches for inputting a rotation angle. A variable time delay circuit incorporates this rotation angle to electronically increase or decrease the measured magnetic heading angle. This electronic rotation provides for a method to correct physical misalignment of the heading sensor in the vehicle and to compensate for local magnetic deviation.