Figure 2.3, Square-wave for, eh, undercompensated probe, b, properly compensated probe, and C, overcompensated probe. We will begin with figure b because it is for proper compensation. The square wave starts at the left and goes up for one inch. Then it turns a sharp corner and goes to the right for one inch. Then it turns another corner and goes straight down for 2 inches. Then it turns another corner and goes to the right for one inch. Then it turns another corner and goes straight up for two inches. Then it turns another corner and goes to the right for one inch. Then it turns another corner and goes straight down for two inches. Then it turns another corner and goes to the right for 1 inch. And finally it turns another corner and goes straight up for one inch where it ends. There are two complete cycles of the wave. Now that you have the basic square wave in mind the following descriptions won't be as tedious. Part eh of the figure is for an undercompensated probe. When the wave goes up it does not go all the way to the corner but starts to make a gradual transition from vertical to horizontal. The next corner is sharp going down but at the bottom it again makes a rounded off corner. Starting back up it makes a sharp corner at the bottom but a gradual corner at the top. It continues in this way for the rest of the wave. Part c shows the wave produced by an over compensated probe. The wave starts upward but actually goes past where it should turn by perhaps 3/8 inch. Realizing its mistake it makes a U turn and starts back down but it makes a gradual turn to the horizontal part of the wave. It gets the next corner right and sharp but at the bottom it overshoots the mark once again. It goes back up but makes a gradual curve into the horizontal direction. It continues in this same way for the rest of the wave. This completes the verbal description.
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