Tektronix 6 series, Печатная инструкция

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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 display of the graticule relative to the waveform display (position is a display control). That
is all position does; it does not determine what data is acquired as do vertical scale and offset.
■ As you vary vertical offset, the middle voltage level moves relative to zero. This moves the waveform display up or down
relative to the acquired waveform. With input signals that are smaller than the window, it appears the waveform moves in
the waveform view. Actually, the offset moves the middle of the waveform display up and down on the input signal. Offset
moves the waveform display to control the portion of the waveform amplitude the display captures.
■ Applying a negative offset moves the vertical range down relative to the DC level of the input signal. Likewise, applying a
positive offset moves the vertical range up.
Horizontal acquisition considerations
The instrument lets you define the horizontal waveform display parameters that determine which segment of an incoming signal
becomes the waveform record, following acquisition.
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 display relative to any waveform, allowing you to scale it to
contain a waveform edge, a cycle, or several cycles.
Waveform acquisition concepts
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