| 摘要 |
PURPOSE:To transmit surely voice information to a subscriber itself registered in advance, by monitoring a predetermined multi-frequency signal transmitted from a subscriber and a response of the subscriber. CONSTITUTION:An automatic dial transmitting section 1 closes a line to a predetermined subscriber and performs automatic dialing, then a response detecting section 3 monitors the response of the subscriber for a prescribed time. If no response is obtained, the transmission section 1 opens the line at a request of a response detecting section 3, and a counter section 6 counts a prescribed time and starts recalling to the transmission section at the end of count. When a response is given, a response detecting section 3 gives a start to a voice information generating section 2, a signal transmitting section 4 and a signal receiving discriminating section 5, and then monitors the line open of the subscriber. An information generating section 2 transmits a voice signal to the subscriber, and the signal receiving section 4 waits for the receiving of the multi-frequency signal comprising two frequencies in the voice band transmitted and the discriminating section 5 monitors the presence of the receiving. |
