.The main screen represents a transmission line. The pattern represents the signal at every point along the line in real time. The left edge of the screen at the upper right represents the instantaneous signal level at the very beginning of the trace, and the left edge of the screen at the lower right represents the same thing for the far end of the trace. In this way, you can visualize what is happening at every point along the line.

 The Input waveform selection enables you to select a single step-function change in voltage, a single pulse, or a repetitive square wave (much like a clock signal) as the driving signal. The three text boxes allow you to specify the characteristic impedance of the transmission line, and the resistive loading at each end. Having set these, the right arrow then starts the selected waveform down the trace. The waveform will reflect back and forth for at least 5 cycles, illustrating what happens to the waveform under various termination conditions. The speed at which the waveform travels is controlled by the speed selector slider.

 The other two selection buttons allow you to pause or reset the simulation.

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