The rotational position of an encoder magnet can be scanned over more than 360° by respective sensor elements in that magnets are disposed on different stages of a suitable transmission, in particular of a differential transmission, and the magnets are scanned by separate sensor elements, whose signals are computed with one another and yield a total number of revolutions.In particular, when an assembly of this type shall be built very small, undesirable magnetic interferences for the sensor elements have to be avoided through flux conductor elements since the interferences distort the measurement results. Thus, a differentiation is made between active and passive flux conductor elements.