258 6000 Series Oscilloscope User’s Guide
6 Displaying Data
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.