| 摘要 |
PURPOSE:To constitute a titled device so that the person himself who is in a remote place can talk with a visitor standing at the door, by connecting an interphone and a telephone set. CONSTITUTION:When a visitor A pushes a calling push-button 2, telephone lines L1, L2 are closed through a line transformer LT by an FF-1 and a relay Y-1. When a dial tone is sent from an office, a dial tone detecting circuit 9 detects it, and an FF-2 is set. When the FF-2 is set, a motor M is driven to traverse an endless tape 13 in which abbreviated dialing is recorded and to send the abbreviated dialing to the office through a head RPH-1, an amplifying circuit 16, an analog switch 12 and a line switch LT. In this way, even the person himself who is in a remote place can talk with a visitor standing at the door. |
