User Manual

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In roll mode, triggering is not supported. The time reference point on the screen is the right edge
of the screen and refers to the current moment in time. Events that have occurred are scrolled
to the left of the reference point. Since there is no trigger, no pre-trigger information is available.
If you would like to stop the display in roll mode, press the Run/Stop button. To clear the display
and start another acquisition in roll mode, press the Run/Stop button again.
Use roll mode on low-frequency waveforms to yield a display a waveform much like a strip chart
recorder does. At slow sweep speeds, you may want to capture a single trigger (press the Single
button in the Trigger section). When the sweep is finished, the waveform's information will stay
on the screen.
The Zoom Function
Zoom is a horizontally-expanded version of the normal display. You can use Zoom to locate and
horizontally expand part of the normal window for a more detailed (higher-resolution) view of
signals.
Press the HORIZONTAL Scale Knob to turn on the zoom function; press the button again to turn
off the zoom function. When Zoom function is on, the display divides in half. The top half of the
display shows the normal time base window and the bottom half displays the waveform at a
faster sweep speed.
Figure 20 – Zoom function
The area of the normal display that is expanded is outlined with a dark box and the rest of the
normal display is gray. The darker area shows the portion of the normal sweep that is expanded
in the lower half of the screen.
Normal time
Zoomed time base