| 摘要 |
<p>PURPOSE:To automatically measure the fault scale and the fault position at the time of evaluating them by applying a transmission pulse (b) from one end of a cable to be measured and measuring a reflected pulse (c) from a fault point. CONSTITUTION:A propagation loss characteristic D of a cable 4 to be measured is preliminarily set in a storage part 13, and this characteristic value is successively read out from the time of pulse sending in accordance with the elapse of time and is compared with the reflected pulse (c) by comparators 17a and 17b. The characteristic value is successively changed until it coincides with the level value of the reflected pulse, and the level value of the reflected pulse is calculated based on the characteristic value for coincidence. A time T elapsed from the time of transmission pulse output to the time of reflected pulse detection is measured, and a fault position L is calculated based on this time T.</p> |
