| 摘要 |
PURPOSE:To realize the switching of a talking line by switching and controlling a channel changeover switch provided at each channel device by a power line carrier control terminal device in response to the channel device. CONSTITUTION:Each house 61-6n is provided with a door-phone slave set 7, an indoor slave device 8, and an indoor master device 9, the master set 9 is connected to a talking line 11 via the changeover switch 10, a common gate door 5 has a slave set 12, connected to the line 11 via changeover switches 13, 14, a manager room 1 has a master device 15 and a handset 16 and connected to the line 11 via a changeover switch 17. Further, a power line carrier control terminal device 18 is provided to each home 6, the gate door 5, and the room 1, the control information is transmitted and received via the power line 4, and the switches 10, 13, 14, 17 are controlled switching in response to the control information and the connection between the line 11 and each channel device is switched. |
