Door-bell installation esp. for multi-dwelling building - conveys coded calls from outdoor key=pad via mains wiring to corresp. coded pluggable receivers in apartments

摘要

A central transmitter (6) within the entrance hall (4) near the door (7) is wired (9) to an exterior keypad (8) on which each key (12) produces a code assigned by means of an interior keyboard (13) to one of the apartments (3). The transmission is amplified (14) and conveyed through the distribution network (4) to the feeder cables (5) which serve individual apartments. The receiver (11) preset to respond to the assigned code can be plugged into any socket (10) in the apartment concerned. USE/ADVANTAGE - Can be installed easily and quickly, esp. in large houses converted into flats, without very complex wiring.