Pan And Zoom - Agilent Technologies InfiniiVision 5000 Series User Manual

Pan and Zoom

InfiniiVision Oscilloscopes User's Guide
The ability to pan (move horizontally) and zoom (expand or compress horizontally) an
acquired waveform is important because of the additional insight it can reveal about the
captured waveform. This additional insight is often gained from seeing the waveform at
different levels of abstraction. You may want to view both the big picture and the specific
little picture details.
The ability to examine waveform detail after the waveform has been acquired is a benefit
generally associated with digital oscilloscopes. Often this is simply the ability to freeze
the display for the purpose of measuring with cursors or printing the screen. Some digital
oscilloscopes go one step further by including the ability to further examine the signal
details after acquiring them by panning and zooming through the waveform.
There is no limit imposed on the zoom ratio between the sweep speed used to acquire the
data and the sweep speed used to view the data. There is, however, a useful limit. This
useful limit is somewhat a function of the signal you are analyzing.
In normal display mode, with vectors (connect-the-dots) off, you can zoom in to the point
where there are no samples on the screen. Obviously, this is far beyond the useful limit.
Likewise, with vectors on, you can see the linear interpolation between the points, but
again, this is of very limited value.
Zoom
The screen will still contain a relatively good display if you zoom in horizontally by a factor of 1000
and zoom in vertically by a factor of 10 to display the information from where it was acquired.
Remember that you can only make automatic measurements on displayed data.
To pan and zoom a waveform
You can pan across and zoom-in on a waveform even when the acquisition system is
stopped.
1 Press the [Run/Stop] key or the [Single] key and allow the oscilloscope to acquire
the waveform and stop. The [Run/Stop] key is illuminated red when the oscilloscope
is stopped.
2 Turn the horizontal sweep speed knob marked
volts/division knob marked
The  symbol at the top of the display indicates the time reference point where the
zoom-in/zoom-out is referenced.
to zoom horizontally and turn the
to zoom vertically.
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Displaying
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