To provide a noise terminal voltage suppressing means for an equipment using high frequencies.

The wiring between a commercial AC power supply 1 and a capacitor 2 for preventing noise is connected so that it crosses at least once, and thereby the connection wiring is divided into a plurality of blocks by the cross points. The cross points of the wiring is set so that a quantity of change in magnetic flux which interlinks with each odd-numberth block counted from the commercial AC power supply 1 toward a DC power circuit 3 may be nearly equal to a quantity of change in magnetic flux which interlinks with each even- numbered block.