Monitoring the S
DI Physical Layer
To Manually Mea
sure Jitter Using
the Eye Display
NOTE. If you use the measurement
cursors to measure jitter, you may get a
different result than that shown in the jitter
thermometer for the following reasons:
The internal peak detector does a better
job of measuring jitter excursions than
manually positioning the cursors.
The noise floor is removed from the jitter
measurement readout but not from the
cursor delta readout.
1. Pe rform the initial setup for Eye
measurements. (See page 61, Ta k i n g
Eye M easurements.)
2. Use the LINE SWEEP button to select
the 3EYE mode, which shows peak jitter
at each eye crossing.
3. Use the Eye pop-up menu to set the jitter
high-pass filter to one of the following:
To measure timing jitter, select the
10 Hz filter for both SD and HD
signals, or select the Timing filter.
To measure alignment jitter, select
the 1 kHz filter for SD signals or
select the 100 kHz filter for HD
signals, or select the Align filter.
68 Waveform Rasterizers Quick Start User Manual