| 摘要 |
<p>The characteristics of an a.c. waveform are determined by measuring the time interval between the instant when the waveform crosses a first reference threshold (12) and the instant when it crosses another threshold (14). The second threshold is varied to obtain a series of time interval measurements from which a point by point reconstruction of the waveform can be made. The technique has the advantage that it can be used to characterise waveforms whose arrival time is indeterminable. <IMAGE></p> |
