| 摘要 |
PURPOSE:To select and control a line wire state presentation, a connecting means and a channel switching operation of a key telephone set based upon a set up mode by providing a necessary operation mode by a set up means which is controlled by a control part and judging a condition whether a specified line wire is in use or not by a main station and whether an incoming from the specified line wire is present or not, after setting up the connecting condition of the main station with the specified line wire as an initial state. CONSTITUTION:An off-hook on one of the key telephone set ST6 is operated, it is received by a control part CNT14 and a key operation of a keyboad 68 becomes a same condition, and the control part CNT14 controls a channel switch 12 according to either operation by a line wire button, an extension key or a dial key and a switching is performed. Along with this, a dial outgoing is applied by the control of a relay D1 or MF signal oscillation circuit MFG17 when it is a line wire outgoing and an extension ringing tone is sent by the control of a tone control circuit TCC62 against the key telephone set ST6 on the other end of a line when extension outgoing. |
