This is a simple circuit using a transmission line. The wave goes across the transmission line and is reflected at the other end, because the line is not terminated properly. This creates a standing wave on the line, which is a wave that oscillates but does not appear to travel. It is actually the combination of two waves (the initial wave, and the reflected wave) traveling in opposite directions.
In the scope, you can see that the peak voltage across the resistor doubles as soon as the wave is reflected, 4 nanoseconds after the oscillation starts. Click the Reset button to see it again.
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