Reference

Reporting Jitter Measurement Errors. When enabled in the Physical Alarms submenu of the Configure menu, the Jitter alarm will be reported to the Event Log in only the following two conditions:

HWhen the Jitter display is selected

HWhen the Event Log or Alarm Status displays are selected after the Jitter display is selected

That is, if you enter the Jitter display and then use the STATUS button to view the Event Log or Alarm Status displays, the jitter measurement alarm will be active. If you select another display mode such as Eye or Waveform, the jitter measurement alarm will be disabled.

Use the Set Default Thresholds soft key to set the thresholds back to the default values for the type of signal you are monitoring: SD (SMPTE 259M) or

HD (SMPTE 292M). The default value for the jitter measurement 0.2 UI, which is the maximum alignment jitter specification for both SD and HD signals and is the maximum timing jitter specification for SD signals (see Table 3-3).

Since the maximum timing jitter specification for HD signals is 1.0 UI, you must set the high-pass filter to 10 Hz and manually set the jitter threshold to 1.0 UI before the instrument will properly generate an alarm if the HD signal exceeds the SMPTE 292M timing jitter specification.

Use the Set Meas. Thresholds soft key to set a custom threshold level.

Table 3- 3: Jitter measurement alarm thresholds

Signal type

High pass filter setting

Alarm threshold

 

 

 

SD (SMPTE 259M)

10 Hz (timing jitter)

0.2 UI (740 ps)

 

1 kHz (alignment jitter)

0.2 UI (740 ps)

 

 

 

HD (SMPTE 292M)

10 Hz (timing jitter)

1.0 UI (673 ps)

 

100 kHz (alignment jitter)

0.2 UI (134 ps)

 

 

 

WFM700 Series Waveform Monitors User Manual

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