| 摘要 |
PURPOSE:To enable recording of the data of the seismic wave with high reliability, without recording of noises of impulse character as the data of the seismic wave, by detecting the wave through both data of the amplitude and time length of the wave. CONSTITUTION:The data of the seismic wave is transmitted from a transmission device 11 through an electric communication circuit 10 and, when the amplitude thereof is larger than the value of the amplitude of the seismic wave jndged to be an earthquake, the value of amplitude judged to be the seismic wave is outputted from an amplitude judging circuit 12. Meanwhile, when the time continuation T is judged to be longer than the time width TAU judged to be of an earthquake by a time-continuation judging circuit 13, the data of the seismic wave are recorded by a recorder 15 based on the output of an AND gate circuit 14 which obtains the input from both judging circuits 12 and 13. Even if noises of impulse character are induced in the circuit 10, detected as the seismic wave in the circuit 12 and the amplitude thereof is inputted in the AND gate 14, the output can not be obtained from the circuit 13, since the noises of impulse character does not meet the condition of T>r. Accordingly, the seismic wave is not outputted from the circuit 14 and thus the data of the seismic wave are not recorded in the recorder 15. |
