Tektronix WVR8200 User Manual page 87

Elements of the Eye
display
Eye display pop-up menu
Usage notes
WVR8200 and WVR8300 User Manual
Link: Shows from which link the signal is originating
Eye Pattern: Displays a waveform you can use for SDI transport verification
and analysis.
Jitter Thermometer: Displays jitter value and relates it to alarm limits.
Equalized Eye Indicator: If enabled in the CONFIG menu, the Eye pattern
is equalized, reducing the jitter noise floor. Amplitude Cursor measurements
do not indicate the actual signal amplitude.
Cursor Readouts: Provide for direct measurements of amplitude and time
on the Eye.
Eye Pattern Type: Either 3 Eye, or 10 Eye (SD)/20 Eye (HD). The latter
types can help reveal when jitter at the parallel word rate is present.
Jitter HPF: Indicates the setting for the Jitter High Pass Filter, set in the
CONFIG menu.
The Eye pop-up menu allows you to choose from two display types: Eye and
Jitter. It allows you to do the following:
Jitter1 HP Filter: Select the HP filter to be Timing, Align, 10 Hz, 100 Hz,
1 kHz, 10 kHz, or 100 kHz.
Center Waveform: Press the SEL button to center the waveform.
Jitter Meter: Select to not display the jitter meter or readout (Off), Meter
Only, Readout Only, Meter and Readout.
Enable Measure: Press the SEL button to enable eye measurement.
Display Type: Select from Eye or Jitter display.
At the end of a long cable, the eye diagram may appear so noisy that there is little
or no discernible opening. In this situation, limited use of the eye diagram is
still possible by selecting Equalized Eye mode. The equalizer compensates for
the effects of cable length by applying an inverse response function and then
reslicing the signal to a logic level. This causes amplitude information to be lost,
but preserves the effects of jitter in the signal.
If the equalized eye display appears clear with a substantial eye opening, then the
signal is likely to be recovered error-free. However, if it appears noisy with little
eye opening, then there is more potential for data errors to occur in the receiver.
Display information
67