PURPOSE: To transmit a signal and improve working efficiency by mounting an insulating film where a signal transmitting coil is wound to the core and also mounting flexible printed wiring substrate which can transmit a signal sent from the coil to the edge of coil.

CONSTITUTION: Two grooves 9 and 10 for first and second channels are formed coaxially on the surface of core 8 and the groove 11 for eliminating crosstalk is also formed therein. The grooves 12, 13 for extracting coil are formed toward the external side from the groove 10. The coils 14, 15, 16 are formed on the insulating coils 17, 17, 17, the insulating film is inserted into the grooves 9, 10, 11 and the edge is connected to the printed circuit substrates 18, 19 for lead out. Thereby, the coils 14, 15 for transmitting signal can be formed.