Abstract: A ring transformer having a core, at least one winding and at least two flanges, and a rotor plate packet having at least one winding is arranged on a rotor shaft before the winding process. A coil body having at least two wind-on connectors is arranged on the transformer core. The wind-on connectors are offset relative to one another and a section of wind-on connectors radially projects outside the circumferential contour of the ring transformer. The winding wire ends of the transformer winding are secured to the wind-on connectors during the winding of the synchro system. The section of the wind-on connectors projecting outside the circumference of the ring transformer is subsequently removed. In this way, the iron parts of the rotor winding and of the ring transformer can be mounted in advance on the rotor shaft and all windings can be continuously wound in one work process.