| 摘要 |
PROBLEM TO BE SOLVED: To provide an emergency reporting device capable of easily detecting the abnormality of a telephone line by a loop signal level of a transmission signal. SOLUTION: The emergency reporting device 1 capable of monitoring and controlling the abnormality of an elevator or facility in a building via an analog telephone line from a distant place is provided with a modem 3 for transmitting/receiving data using a modem signal and a PB signal etc., a hybrid circuit 6 for converting the data between the emergency reporting device of an analog telephone line and a public telephone network 10 for data communication, a network control device 7 for connecting the hybrid circuit to the public telephone network, a level detector 8 for detecting the level of the loop signal of the transmission signal of the hybrid circuit, a storage device 9 for storing level information of the loop signal detected by the level detector, and a central processing unit 2 for detecting the abnormality of the analog telephone line. COPYRIGHT: (C)2005,JPO&NCIPI
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