Doorbell – sound mechanism
Installation of a doorbell in an apartment : Doorbell Sound Mechanism
Quote from Article entitled Installation of a doorbell in an apartment:
Depending on the connection method, doorbells are divided into two types:wire;wireless.
Wire doorbells operate off the electricity, and off an independent power supply. The button and the sound panel of these devices are needed to be connected to each other by wires. Wireless bells do not require a physical connection of elements.
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