Tektronix, Inc. P6240, Руководство пользователя

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Measurements
TLS 216 User Manual
2–29
H
Independent mode cursors operate as was earlier described; that is, you move
one cursor at a time (the active cursor) using the general purpose knob, and
you use the SELECT button to toggle which cursor bar is active.
H
Tracking mode cursors operate in tandem: you move both cursors at the
same time using the general purpose knob. To adjust the solid cursor relative
to the dashed cursor, you push the SELECT button to suspend cursor
tracking and use the general purpose knob to make the adjustment. A second
push toggles the cursors back to tracking.
You can read more detailed information about how to use cursors in Measuring
Waveforms with Cursors, beginning on page 3–81.
You make automated measurements merely by pressing a few buttons. The logic
scope does all the calculating for you. Because these measurements use the
waveform record points, they are more accurate than cursor or graticule
measurements.
Press the MEASURE button for the automated measurement menus. These
menus let you make amplitude (typically in volts; sometimes in %), time
(typically in seconds or hertz), and area (in volt-seconds) measurements.
Although the logic scope scales and positions waveforms in groups, it takes
automated measurements on or between individual waveforms. You can select
and display up to four measurements, each taken on an individual waveform
channel, at a time. (Some measurements, such as Setup, Hold, and Skew, are
taken on more than one waveform. See Table 3–3 on page 3–68 for a list of all
the automatic measurements and their definitions.)
You can make automated measurements on the entire waveform record or just on
a specific part. The gating selection in the Measurement menu lets you use the
vertical cursors to limit the measurement to a section of the waveform record.
The snapshot selection in the Measurement menu lets you display almost all of
the measurements at once. You can read about snapshot under To Take a
Snapshot of Measurements on page 3–78.
Automated measurements use readouts to show measurement status. These
readouts are updated as the logic scope acquires new data or if you change
settings.
To Find More Information
See Appendix B: Algorithms, for details on how the logic scope calculates each
automatic measurement.
See Example 3: Automated Measurements, on page 1–23, for a tutorial on
automatic measurements.
Automated Measurements