Tektronix CSA7404B, User Manual

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Acquiring Waveforms
CSA7000B Series & TDS7000B Series Instruments User Manual
3- 23
Independent vs. Shared Window. The instrument applies the same horizontal
acquisition window to all channels from which it acquires data. Unlike the
vertical acquisition window that you size and offset independently for each
channel, the same time/div, resolution (record length), and horizontal position
(from the same trigger point) apply to all channels simultaneously. One trigger,
from a single trigger source, will locate a common horizontal acquisition
window for all active channels, which you can shift in parallel by setting the
horizontal position control.
The horizontal acquisition window determines the waveform records extracted
from all signals present at all active channels. You can think of the horizontal
acquisition window as cutting across any input signals present in the input
channels to extract the same slice of time into waveform records. See Figure 3--5.
Ch4 record
Ch3 record
Ch2 record
Ch1 record
Common horizontal
position and delay
Common trigger
Common record start
point and record length
Figure 3- 5: Common trigger, record length, and acquisition rate for all channels
Setting Acquisition Controls
This section presents overviews of the instrument acquisition features—those
that start and stop acquisitions and those that control how the instrument
processes the data as it is acquired (just sampled, or averaged or enveloped).
Special features, keys to using, and operation controls are covered.