Abstract: A circuit for controlling the intermittent application of a dc potential to a device, such as a striker mechanism for a gong, having a member reciprocally moveable between rest and active positions. The reciprocating member shunts and unshunts a capacitor when the member is in its rest position and moved away therefrom, respectively. While the capacitor is shorted, and during its charge time, dc power is applied to the device. When the capacitor is charged to a predetermined potential, dc power is disconnected from the device thereby allowing the reciprocating member to return to its rest position to shunt the capacitor and initiate a new cycle of operation. The system is substantially independent of mechanical characteristics of the device and the current interrupted or made by the contact pair may be at least an order of magnitude less than the peak current in said device.