HP 54620A, User'S And Service Manual

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You can detect the presence of aliases in the analyzer’s display simply
by selecting a faster sweep speed. If the waveform display changes
more than expected, it is an alias being caused by undersampling.
Whenever a waveform is being displayed as a solid bar, it is highly
likely that when you expand the waveform the display will contain
aliases.
Aliasing Produces Misleading Information
Aliasing produces misleading information. The glitch detect circuitry helps
prevent aliasing by identifying additional transitions that occur between
samples.
Whenever the waveform display is not as expected, it might be an alias—the
result of undersampling. Always try to use a sweep speed that produces a
sampling interval that is at least 1/2 of the shortest time interval to be acquired.
To take a single acquisition
•
Press
Single
.
The analyzer starts the acquisition system and begins searching for the
trigger condition.
When the analyzer is in Autostore mode (see “To accumulate the results of
every acquisition”) pressing Single adds the results of the new acquisition to
the current display contents.
See “To define the trigger mode” in this chapter for more information on how
the analyzer’s trigger mode affects handling of the trigger condition.
Making Analyzer Measurements
To take a single acquisition
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