PURPOSE: To improve the operability and to prevent tapping for the titled telephone device by enabling a user to register optionally a secret number and an operation state indication number.
CONSTITUTION: A call signal sent from a trunk line terminal l is detected, and a switch 2 is changed over by a switch control circuit 4 for reproduction of an answer message. A secret number is uttered to a telephone by a calling subscriber while he/she hears an answer message. Then the secret number is sent to a sound recognizing circuit 6 and collated with the registered data. When coincidence is obtained from said collation, a CPU9 sends the data given from the circuit 6 to a collation circuit for decision of coincidence with a secret number registered to a memory 14. If the coincidence is obtained, the working of a tape recorder part 7 is stopped to decide whether or not the sounds indicating an action state are delivered. Then an action indication corresponding to an adapted action indication is executed when the sound signals indicating an action state are sent and coincident with the signals registered in the memory 14.
KAGEYAMA SHIYUUJI
ONO YASUSHI
| JPS5467708A | 1979-05-31 | |||
| JPS564964A | 1981-01-19 |
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