Electronic multitone gongs with a start circuit which can be triggered by a bell button of a house bell system, a tone generator and a controlling clock generator and an AF amplifier feeding a small loudspeaker require a power supply which is usually represented by a dry cell battery and in some cases also by a separate power supply unit. To be able to operate the electronic multitone gong also without separate battery or mains installations, the connection to the bell button is connected to a voltage-multiplier rectifier circuit having a high storage capability which takes over the power supply to the gong. In this arrangement, the start circuit is constructed in such a manner that it triggers the gong as soon as the voltage present after a rectifier circuit exceeds a predetermined voltage value. A voltage monitoring stage can determine when the dropping voltage drops below a minimum value required for operating the gong and then switch the gong off or over, continuously increasingly attenuate the AF amplifier and switch the arrangement back to its original switching state.
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