| 摘要 |
A solid state compass system for use with automobiles or the like. The system consists of a dashboard mounted readout unit which receives signals provided thereto from a remotely located solid state magnetic bearing sensor, the latter being responsive to the earth's magnetic field. The solid state magnetic bearing sensor described herein, includes a pair of Hall effect semiconductors and ancillary electronic circuits. Two ancillary circuit types are described. One circuit is designed to output digital codes indicative of magnetic heading; the other circuit is designed to output two currents which are indicative of sine and cosine components of magnetic heading. The circuit designed to output digital codes includes sinusoidal waveform generators, a binary counter, a differential comparator amplifier and digital latch and decoding circuits. The circuit designed to output currents indicative of sine and cosine components of magnetic heading are comprised of a pair of linear differential buffer amplifiers. The dashboard mounted readout unit designed to accept digital codes may be defined by a plurality of discrete indicators, such as light emitting diodes, or segmented alpha indicators or so forth may be employed. The dashboard mounted readout unit designed to accept two currents which are indicative of sine and cosine components of magnetic heading may be characterized as a pointer which is pivoted about an axle by the influence of the magnetic field induced by a surrounding stator whose windings receive the aforementioned two currents. The solid state sensor unit is preferably located at a point on the vehicle distant from large bodies of iron or steel and where the earth's field is strong relative to fields associated with permanently magnetized auto parts.
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