| 摘要 |
PURPOSE:To prevent the erroneous actions of an electric control circuit by constituting a titled device so as not to supply the electricity for charging of a power source circuit to a line use detection circuit. CONSTITUTION:The main battery 8b of the power source circuit 8 is charged with the electric power supplied from a telephone line network L and a terminal device 2 is made to be actuated by using the electric power charged in the main battery. The main battery 8b of the power source circuit 8 is charged with the electricity of the telephone line network L, which is supplied to the telephone line network L side of the line use detection circuit 61 in a network control device 6. When the terminal device 2 does not execute the control of transmission, the switch 66a of a DC circuit 66 is opened by a circuit switching relay 65 in order that the electricity is not supplied to the line use detection circuit 61. Thus there happens no objectionable point that the terminal device 2 does not execute the control of transmission by erroneously actuating with considering that the telephone line network L is in used condition.
|
