| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce power consumption and to easily clear EMI regulations. <P>SOLUTION: In the intercom system for a multiple dwelling house, in which a living room master unit 2 called by an entrance unit 11 of the multiple dwelling house sends the signal of operation start onto a living room monitor 22 and video picked up by an entrance camera 12 of the multiple dwelling house is outputted from a video controller 4 via respective systems onto the living room monitor supplied with power from a monitor power source circuit 44, the video controller is provided with a current detecting circuit 45 for detecting a change in the current supplied to the living room monitor which starts the operation and detecting a system connected with that living room monitor and a system switching circuit 43 for sending a video signal to the system connected with the living room monitor detected by the current detecting circuit and disconnecting systems except for the system connected with the living room monitor. <P>COPYRIGHT: (C)2003,JPO |
