| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an earthquake survey system which can have a wired and a wireless transmission line, arranged partially by free choice according to the state of a survey area. SOLUTION: This earthquake survey system includes data gathering terminal devices 2, a central recording device 1 which records data gathered by them, and a cable line 11 or radio data transmitter receiver as a digital transmission line. A data gathering terminal device has a means which receives a control signals from the central recording device and repeats it to a downstream transmission line, and a means which adds its data signal to the data signal sent upstream in response to the control signal and sends them to the upstream transmission line. The central recording device 1 has a send-out means for the control signal and a receiving and recording means for a data signal. The radio data transmitter receiver has a means, which selectively sets an operation radio frequency by specifying characteristic addresses for respective data transmitter receivers from a radio command transmitter prior to device operation and a means which transmits the control signal and data signal from the data gathering terminal device, instead of a cable line.</p> |
