| 摘要 |
A device for testing an electrical line by time domain reflectometry, using a pulse generator to generate a series of test pulses, a programmable delay generator which provides a delay in the transmission of the test pulses, and an analog to digital converter which samples the reflected signals from the line and sends them to memory. The test pulse is transmitted to the line and a number of digital sample values are produced sequentially at a defined sampling rate by the delay generator, which is incremented or decremented to advance or retard the transmission of the test pulse by 1/n times the sampling period, and sample values from each pulse obtained. The above steps are repeated until transmission of the test pulse has been retarded or advanced by at least (n-1)/n times the sampling period and sample values from each pulse obtained, with the sampled values arranged in order of increasing time difference between transmission of the test pulse and sampling.
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