Tektronix WVR6020, Техническое описание

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Video and General Performance Veri fi cation
HD Jitter Waveform
Accuracy (Option HD
and PHY)
This test checks for jitter waveform accuracy.
1. Connect the HDVG1, HDST1, and rasterizer as described in HD Jitter Noise
Floor .
(See page 84.)
2. Set tile 2 for Jitter display as follows:
a. Press the DISPLAY SELECT 2 button.
b. Press and hold EYE (or MEAS if there is no EYE button), and then select
Display Type > Jitter Display.
c. Press the DISPLAY SELECT 2 button to close the menu.
d. Press MAG and FIELD for a sweep rate of 150 us/div.
3. Adjust the HDST1 module SDI parameters as follows:
a. Set the jitter (LF) frequency to 9950 Hz and set the jitter (LF) amplitude
to 0 UI.
b. Slowly increase the jitter (LF) 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 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 the HD Jitter Waveform Accuracy.
6. Turn Cursors OFF.
7. Reset the generator.
Waveform Rasterizers Speci fi cations and Performance Veri fi cation 87