Compact magnetic compass - has photoelectric potentiometric read=out in package connected by flexible spring wires to supporting rings

摘要

The compass card (1) is free to rotate with up to 15 deg. tilt about a pivot (5) fixed in the base of its package (19). A radial slot (3) parallel to its two bar magnets (2) sheds light from a lamp (9) and cylindro-conical reflector (7) on to an open circular photoresistive track (10) surrounding the pivot. The package is mounted within square outer and inner support rings (17,18) and carries a flexible printed circuit card (25) connected by a bridge (21) of spring wires to a corresp. card (24) integral with the inner ring (18). A third case (23) integral with the same ring is connected by a second bridge (20) to a fourth card (22) integral with the outer ring (17).