HOUSE INFORMATION BOARD SUBORDINATE MASTER UNIT, HOUSE INFORMATION BOARD MASTER UNIT, AND SECURITY MONITOR AND SPEECH COMMUNICATION SYSTEM USING THE UNITS

摘要

PROBLEM TO BE SOLVED: To provide an originally improved house information board master unit so as to output an alarm sound from a subordinate master unit even when the subordinate master unit does not work due to power failure, in the case a system of hands free is constructed. SOLUTION: A house information-board subordinate master unit B is connected to a house information-board master unit A having an emergency power function, a security monitoring function, and at least an extension speaker connection terminal T1, through a voice communication line La, a voice signal line Lb and a control signal line Lc. The subordinate master unit B is provided with a hands-free voice communication means 201 for voice communication with the house information-board master unit A. The subordinate master unit B also includes a master-unit connection terminal T2 for connecting to the extension speaker connection terminal T1 of the master unit A through a voice signal line Ld; a speaker connection switching means RY3 for switch-connecting a speaker SP of the voice communication means 201 to either the voice line d connected to the master-unit connection terminal T2, or an output terminal of the speech communication means 201; and a control means 25 for monitoring power supply to the subordinate master unit B and controlling to switch the speaker connection switching means RY3 depending on the existence of power supply. COPYRIGHT: (C)2004,JPO&NCIPI