Tektronix TBS2072, Руководство пользователя

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Trigger setup
Triggering on a speci fi ed pulse width
Use this procedure to set the oscilloscope to trigger on a speci fi ed signal pulse condition. You can trigger when a pulse is
less than, greater than, equal to, or not equal to a set time period (width). The minimum pulse width setting is 1 ns. (See
page 27,
Available trigger types .)
Pulse width triggering is most often used to troubleshoot or analyze digital signals.
1. Push the Trigger Menu front-panel button.
2. Push the Type side-menu button.
3. Use the Multipurpose knob to select and click Pulse Width .
4. Push the Source side-menu button and use the Multipurpose knob to select and click the channel to use as the trigger
signal source, or select AC Line to use the AC power source frequency as the trigger signal.
5. Push the Polarity side-menu button and use the Multipurpose knob to select and click the pulse polarity (positive
or negative) to trigger on.
6. Push the Threshold side-menu button and use the Multipurpose knob to select and click the trigger level entry method:
Click the threshold fi eld and use the Multipurpose knob to manually set the trigger level.
Click Choose Preset and use the Multipurpose knob to set the trigger level to a prede fi ned signal logic family level
(TTL, CMOS, ECL, and so on) or to 0.
Click Set to 50% to set the trigger level to 50% of the signal peak-to-peak level.
7. Push the Trigger When side-menu button and use the Multipurpose knob to select and click the pulse width condition on
which to trigger. Then use the Multipurpose knob to enter the pulse width time parameter.
TBS2000 Series User Manual 37