Tektronix WVR6020, Technical Reference

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Video and General Performance Veri fi cation
SD Jitter Waveform
Accuracy (Option PHY)
This test checks the SD jitter waveform accuracy.
1. Press the FULL button to return the display to 4-tile mode.
2. Set tile 2 for Jitter display as follows:
a. Press the DISPLAY SELECT 2 button.
b. Press and hold EYE (or MEAS if no EYE button), and then select Display
Type > Jitter Display.
c. Press MAG and FIELD for a sweep rate of 150 us/div.
3. Adjust the DVG1 SDI module parameters as follows:
a. Set the jitter frequency to 9950 Hz.
b. Slowly increase the jitter amplitude while watching the Eye display. As
the jitter amplitude increases, the transitions start to get wider and
fi ll
in the space between the transitions. As the jitter amplitude approaches
one UI, the space between transitions disappears (the eye will close). At
one UI of jitter the eye diagram will have "closed", and a darkening, or
shadow, on an eye trace will appear out of the smeared background.
c. Continue increasing the jitter until another shadow of an eye appears.
You now have 2 UIs of jitter.
d. Continue increasing jitter to 3 UIs. Do not adjust for 3 UIs on the
generator; adjust instead for the sharpest narrow eye shadow on the
rasterizer display, which indicates that the applied jitter is precisely 3UI.
This may not be 3 UI on the generator because you are setting it for 3 UI
added jitter instead of 3 UI total jitter.
4. The jitter display should show a nearly stationary sine-wave 3 UI in height.
Check the sine portion of the jitter trace, ignoring the small random noise
component, with the graticule marks and the cursors to see that it is 3 UI
±10% (between 2.7 UI and 3.3 UI).
5. Record Pass or Fail in the test record for SD Jitter Waveform Accuracy.
Waveform Rasterizers Speci fi cations and Performance Veri fi cation 99