| 摘要 |
PURPOSE:To attain stably and automatically dialing by means of microcomputer control by introducing the power supply of the device from a telephone line, and performing turning-on and off of a power supply of the titled device by hook-on and off operation of a handset of a main station. CONSTITUTION:In order to turn off and on a power supply of an automatic dial device(the titled device) in response to hook-on and off of the main station, a modular jack 3 and the main station are connected and also a modular plug 2, a diode rectifier circuit 5 and the modular jack 3 are connected in series with the line. Since the line continues connection during the dial pulse transmission, a constant voltage circuit 7 is subject to votage variation. Then, a relay 10 is driven with a muting signal from an output terminal 1b of a microcomputer 1 during this period, a relay switch 4 is selected from a contact (b) to a contact (a), a chip and a ring of the modular jack 3 is short-circuited, allowing to prevent the dial pulse signal from being leaked to the handset side. Further, the muting signal is inputted to a relay 11 and a switch 9 changes over the power supply of the device to a power supply 8. |
