PURPOSE: To connect the movable member to the power supply without using a flexible wire by providing a transformer, whose primary winding consists of a conducting wire being extended along the moving direction of the movable member, as the power supply for the movable member.

CONSTITUTION: Drawing illustrates an embodiment wherein power is supplied to a lamp 6 provided at a dial pointer 2 for a radio. A conducting wire 3 serves as a primary winding and attached to a pointer 2 is a transformer 5 having a doughut- shape core movable along the wire 3 which penetrates therethrough. An output of the transformer 5 is supplied to the lamp 6 and the light from the lamp illuminates the whole of the pointer 2. With the turning of tuning dial 8, a variable condenser is adjusted and the pointer 2 is moved simultaneously. At this time, the transformer 5 is moved together with the pointer 2.