Tektronix WFM2200A, Руководство пользователя

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Looking at jitter in both displays can help you separate jitter sources to determine
whether they are within a single circuit on a circuit board or from various pieces
of equipment in a system. If you are planning a composite D/A conversion, select
the 10 Hz bandwidth filter to measure total broadband jitter.
The following image shows an example displaying a signal with a lot of jitter. In
the first and second quadrants, the high-pass filter is set for 10 Hz so that all jitter
above 10 Hz is displayed. In the third and fourth quadrants, the high-pass filter is
set for 100 Hz, removing most of the 30 Hz jitter and leaving the spikes. Both
Jitter displays are set for two-field sweep. The upper Eye display shows a fairly
even jitter spread, which suggests a moderately uniform statistical distribution of
jitter. This jitter is from a sine wave component. Notice that there is no indication
of jitter spikes. In the lower Eye display, the jitter is of a low-density haze, which
suggests a less uniform jitter distribution. This is indicated by the spikes.
Figure 58: Measuring jitter
Monitoring the SDI physical layer (WFM2300 only)
WFM2300 and WFM2200A Waveform Monitors User Manual 195