PURPOSE: To reduce a consumption power during waiting by a method wherein a transmitter is provided with a starting signal generating means, which receives a starting signal in radio, and a controller for a waiting starting device is connected to a power source for a given time.

CONSTITUTION: A waiting starting device 4 is intervened between a controller 2 and a battery 5, and the device 4 is provided with a piezoelectric microphone 6, a C-MOS inverter 9, and a timer 10 to automatically turn off, and an output terminal is connected to the controller 2. In a waiting state, the device 4 is brought into a waiting state but the controller 2 is not charged with a current. A supersonic wave transmitted from a transmitter is inputted to a timer 10 through the microphone 6 and the inverter 9. A power source is supplied to the controller 2 during, for example, several seconds, an electric lock is driven by a control signal, and after operation, the power source is automatically disconnected.