Reference

Measurement Accuracy Using the Measurement Cursors. If you use the measurement cursors to measure jitter, you may measure a different result than that shown in the jitter measurement box for the following reasons:

HThe internal peak detector does a better job of measuring jitter excursions than a human can when using their naked eye to position the cursors

HThe noise floor is removed from the jitter measurement readout but not from the cursor delta readout

Manually Measuring Timing Jitter. Perform the following steps to manually measure the timing jitter:

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

2.Select the 3 EYE mode, which shows peak jitter at each eye crossing.

3.Select the 10 Hz bandwidth filter to measure the total broadband jitter (use this setting if composite D/A conversion is planned).

4.Position the timing cursors to measure the width of the Eye zero-crossing point (see Figure 3-9). If necessary, use the Gain and Sweep menus for better vertical and horizontal resolution.

5.Check that delta between the two timing cursors is less than the following over one horizontal line:

H SD signals: 740 ps (0.2 unit intervals per SMPTE259M)

H HD signals: 673 ps (1.0 unit interval per SMPTE292M)

Figure 3- 9: Timing Cursors alignment for measuring timing jitter

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WFM700 Series Waveform Monitors User Manual