Video call for a front door in an apartment. Video door phone. : Video Interphone
Quote from Article entitled Video call for a front door in an apartment. Video door phone.:
With wired devices it is more complicated. A house intercom in an apartment is powered by 220V (110V) wire system. 12V voltage is supplied through a twisted-pair cable to the door panel. Thus, it is necessary to lay out the cable, which will connect both device elements, supply power and video. If you want to install additional cameras or second private plate, they are also needed to lay out the cable.
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