This AC electronic music door bell is composed of general electronic door bell, rectified power supply, relay and power amplifier and does not need battery to power it.

本发明涉及一种用交流电的电子音乐门铃，由普通电子门铃加整流电源、继电器及功率放大器构成。本发明不再需要电池供电。

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However, they point out this problem could be rectified if the markets were re-sequenced, with the gas market clearing before the electric power bidding process.

FORBES: Electricity and Gas Markets Are Out Of Synch: Sooner or Later, This Will Hurt Us