摘要 |
A circuit for actuating a door chime has a dc power source in series with a resistor and in shunt with a capacitor. A remote push button transmits a radio signal to the circuit, to connect a solenoid in series with the power source and the resistor and in shunt with the capacitor, which causes a relatively large pulse of current from the instantaneous combination of the power source current and the current from the charge of the capacitor to be applied to the solenoid which is arranged to strike a tone bar. The resistor in series with the capacitor has a time constant that charges the capacitor adequately between cycles of the operation of the push button and the resistance of the resistor limits the current flow from the power source. |