Agilent Technologies 54621A, Руководство пользователя

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MegaZoom Concepts and Oscilloscope Operation
Acquiring Data
Acquiring Data
The oscilloscope operates like an analog oscilloscope, but it can do much more.
Spending a few minutes to learn some of this capability will take you a long way
toward more productive troubleshooting.
Single versus Run/Stop
The oscilloscope has a
Single
key and a
Run/Stop
key. When you press
Run/Stop
(key is illuminated green when running), the trigger processing rate is
optimized over memory depth. Single always uses the maximum memory
available. When you press the
Single key, the oscilloscope has at least twice as
much memory as when running repetitively. Because more memory is available
when using Single at slow sweep speeds, the oscilloscope will have a greater
sample rate.
When the oscilloscope is running, pressing Run/Stop (key is illuminated red
when stopped), the oscilloscope stops, and several triggers of information could
be displayed on the screen. This will happen in several cases:
• At very fast sweep speeds (2
µ
s/div and faster), you might see less than a full
screen of data per trigger. In this case, we build a picture from several
triggers. Doing this provides a more accurate and responsive display than
mathematically interpolating between points.
• With
Average
acquire mode on, several triggers are averaged together to
reduce noise.
• When using infinite persistence, all triggers remain on the screen.
• At very slow sweep speeds (1 s/div), part of the last trigger may still be on
the screen when the oscilloscope is stopped.