The TDR then displays the reflected signal as information on waveform display. This circuit in this article is made to be used with a normal oscilloscope. The circuit which you build is used as the signal source and the oscilloscope is used as a waveform monitor. The larger the pulse width, the more energy is transmitted and therefore the further the signal will travel down the cable. This circuit includes settings from 10 nanoseconds to 5 microseconds.
Short pulses are ment to test short cables and to locate faults nearby.
When you look at the oscilloscope screen you first see the transmitted pulse and sometime after it you will see the reflected pulse.