Filter
Top Products
Acquiring and Displaying Waveforms
3–50
TDS 500C, TDS 600B, & TDS 700C User Manual
To help you use zoom effectively, consider how it operates on waveforms. When
zooming vertically, the oscilloscope expands or contracts the selected waveform
only. Also, the oscilloscope only positions the selected waveform when in Zoom.
When zooming horizontally, Zoom expands either the selected waveform, all live
waveforms, or all live and reference waveforms, depending on the setting for
Horizontal Lock in the Zoom menu.
When zooming horizontally or vertically, Zoom expands or contracts the
waveform by the zoom factor.
To help you use Zoom effectively, consider how it is affected by interpolation.
When you zoom on a waveform, you expand a portion of it. If the expansion
requires the oscilloscope to show more points for that portion than it has
acquired, it interpolates.
The method the oscilloscope uses to interpolate, linear or sin(x)/x, can affect the
way Zoom displays your waveform. If you selected sin(x)/x (the default), it may
introduce some overshoot or undershoot to the waveform edges. If such is the
case, change the interpolation method to linear, following the instructions on
page 3–52.
To read about the two interpolation methods, see Interpolation on page 3–28. To
differentiate between the real and interpolated samples, set the display style to
Intensified Samples. (See Select the Display Style on page 3–39.)
To quickly determine the zoom factor of a zoomed waveform, select it and check
the Zoom readout. It shows the selected waveform by number, along with the
horizontal and vertical expansion factors.
The Zoom readout appears at the top of the display when zoom is on. (See
Figure 3–25 on page 3–52.) Dual-window (preview) mode does not display the
Zoom readout.
Using with Waveforms
Interpolation and Zoom
Checking the Zoom Factor