Reference

Manually Measuring Rise Time. Rise time measurements of the eye waveform check the performance of sources and signal degradation by cabling. The following procedure provides two methods for manually measuring rise time. The first method uses variable gain to normalize the signal and the second method uses the percentage voltage cursors.

1.Perform the steps in Setup for Eye Measurements on page 3-17.

2.Method 1 - Use variable gain to measure rise time.

a.Use Variable Gain to resize the waveform to 10 major divisions. Position the top and bottom of the waveform on graticule lines.

b.Position the first timing cursor at the crossing of the rising edge of the Eye waveform and the graticule line two divisions above the bottom of the waveform as shown in Figure 3-8.

NOTE. You can use the horizontal MAG control in the Sweep menu for greater accuracy when adjusting the time cursors.

c.Position the second time cursor at the crossing of the rising edge of the Eye waveform and the graticule line two divisions below the top of the waveform as shown in Figure 3-8.

d.The Delta time readout indicates the 20 - 80% rise time measurement.

Figure 3- 8: Timing Cursors alignment for measuring 20- 80% rise time

WFM700 Series Waveform Monitors User Manual

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