| 摘要 |
<p>PURPOSE:To specify a fault location without use of an oscilloscope by obtaining a pulse signal with a drive period eliminated therefrom from a pulse signal being superimposition of a drive pulse signal and a reflected pulse signal so as to obtain an analog signal corresponding to a distance up to a faulty point. CONSTITUTION:A square wave generator 12 and a driver 13 impress pulse signal to a transmission line 11. A directional coupler 14 extracts a reflected pulse signal returned from a faulty location. A receiver 15 and comparators 16, 17 extract a pulse signal whose level is over a setting level from the reflected pulse signal. Furthermore, switches 18, 19 and a switch drive circuit 20 obtain a signal from which a signal for a transmission pulse period is eliminated. The resulting signal is smoothed by LPFs 21, 22 to obtain a signal with a level corresponding to the signal pulse width and the resulting signal is displayed on display devices 23, 24. The level corresponds to a distance up to a fault location. The polarity of the signal corresponds to a short-circuit fault or an open circuit fault at the fault location.</p> |
