Agilent Technologies 54831A User's Quick Start Manual page 72

Across the toolbar are three vertical arrows. These are the left, center, and right
horizontal reference indicators. Clicking on one of these arrows moves the
horizontal position to the respective horizontal reference position on the
display—left, center, or right. Assuming the horizontal position is at zero:
• Left means the information on the display is all post trigger.
• Center means the information to the left of center is pre trigger; to the right
is post trigger.
• Right means the information on the display is pre trigger.
The horizontal position value represents the time relative to the trigger at the
respective horizontal reference. When you change the horizontal sweep speed,
the waveforms expand and contract about this reference position.
Trigger settings and controls The right side of the bar contains the
trigger settings and controls. These will vary depending on the current
trigger configuration, which can be set using the front panel and the
graphical interface. Advanced trigger configuration items are available only
through the graphical interface. You can click on the button labeled with
a "T" to bring up the trigger setup dialog box.
When the scope is set for edge trigger on a particular channel, the trigger level
setting is shown. You can click on it to display a pop-up numeric keypad that
allows you to set a particular trigger level. You can also click on the up and
down arrows to the right of the setting to increase or decrease the trigger level,
respectively. Or, you can click on the trigger reference indicator at the right
side of the display and drag it up or down to change the trigger level.
Using the Oscilloscope
Graphical Interface Mode
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