| 摘要 |
PROBLEM TO BE SOLVED: To provide the communication terminal equipment that changes a dial signal into a touch-tone signal without an operation after dialing. SOLUTION: The terminal equipment that is provided with a function of producing a dial signal and a touch-tone signal and that is connected to a dial line and in use, has a polarity inversion detection circuit 4 that detects polarity inversion of a telephone line L and with a changeover control means 6 that changes the dial signal into a touch-tone signal through the operation of an operation key 5 after an opposite party is called by a dial signal and the polarity inversion element 4 detects polarity inversion.
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