A self-propelled forage harvester is equipped with a crop gathering device which transports crop material from the ground to feed rolls that position the crop for being chopped into small pieces by a chopper drum. The inner assembly includes an elongate inner structure forming a lumen, an elongate conductor extending along an outer surface of the inner structure, and a conductive fitting coupled to the elongate conductor. The first pole portion includes an extending portion that extends so as to cover one surface of a coil facing the second pole portion. Furthermore, a circuit is proposed which is suitable for implementing the method proposed. The present invention also provides a microelectronics device 100 fabricated in accordance with the method.