| 摘要 |
PURPOSE:To avoid causes of generation of coding error such as short break accompanied with switching, and noise or level change, by using a variable resistor. CONSTITUTION:In switching a living line A into a spare line B, a resistor R2 with high resistance is connected between the spare line B and an input/output terminal T and a resistor R1 with low resistance is connected between the existing line A and the terminal T. After cutting of a point shown in the x- mark, the value of the resistor R2 is changed to a low resistance value and that of the resistor R1 is changed to a high resistance value. Then, the resistor R2 is shortened and the resistors R1 and R2 are disconnected from the terminal T. Thus, the spare line B only is connected to the terminal T and the spare line B can be used for communication as the existing line. |
