Note: Amplitude-related automatic measurements (for example, peak-to-peak and RMS) will be accurate for vertical windows if
the waveform is not clipped. But if signal amplitude were to extend outside the vertical acquisition window, the data acquired
is clipped. Clipped data causes inaccurate results if used in amplitude-related automatic measurements. Clipping also causes
inaccurate amplitude values in waveforms that are stored or exported for use in other programs.
If the scale of a math waveform is changed so that the math waveform is clipped, it will affect the amplitude measurements on that math
waveform as follows:
• The vertical position adjusts the waveform relative to the graticule. Adjust the vertical position to place the waveforms where you want
to see them. The waveform baseline indicators indicate the zero Volts (or Amps) level for each waveform. If you adjust the channel's
Vertical Scale, the waveform expands or contracts around the waveform's baseline indicator.
• When you use the Channel Offset control to move a waveform, the baseline indicator no longer represents zero. Instead, it represents
the level of the offset. Offset moves the waveform display to control the portion of the waveform amplitude the display captures. If you
adjust the channel's Vertical Scale, the waveform expands or contracts around the waveform's baseline indicator.
Horizontal acquisition considerations
The instrument lets you define the horizontal waveform display parameters.
These common parameters specify a horizontal scale and position that is applied to all channels simultaneously.
These parameters are shown in the next figure (horizontal window with delay on):
• The trigger position determines where the trigger event will be located in the waveform record. To see more pretrigger data move your
trigger position to the right on the graticule.
• The horizontal position determines the number of pretrigger and posttrigger samples. Samples before the trigger point are pretrigger
samples and those after the trigger point are posttrigger samples. When Delay is off, the horizontal position is the same as the trigger
position.
• The horizontal delay determines the time from the trigger point to the Horizontal Reference.
• The horizontal scale determines the horizontal size of the relative to any waveform, allowing you to scale it to contain a waveform
edge, a cycle, or several cycles.
Using reference waveforms and traces
You can compare a reference waveform or trace to another waveform.
You can create and store a reference waveform or trace. For example, you might do this to set up a standard against which to compare
other waveforms. To recall a previously saved reference waveform or trace:
1. Tap the Add Math Ref Bus button and then tap Ref 1 . This creates a reference badge and displays the reference waveform.
2. Double-tap the Ref 1 badge to open the Reference configuration menu.
3. Tap the Vertical Scale and Vertical Position fields and use the multipurpose knobs to adjust the vertical settings.
4. Tap the Horizontal Scale and Horizontal Position fields and use the multipurpose knobs to adjust the horizontal settings.
5. Double-tap Label and use the keyboard to define labels to display with the reference waveform and trace.
Waveform acquisition concepts
3 Series Mixed Domain Oscilloscope Printable Help
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