Tektronix TPS2000 Series User Manual page 198

Reference
A readout near the top right of the screen displays the current
horizontal position in seconds. An M indicates the Main time base
and a W indicates the Window time base. The oscilloscope also
indicates horizontal position with an arrow icon at the top of the
graticule.
Knobs and Buttons
HORIZONTAL POSITION Knob. Use to control the position of the trigger
relative to the center of the screen.
The trigger point can be set to the left or the right of the center of the
screen. The maximum number of divisions to the left depends on the
Horizontal Scale (time base) setting. For most scales, the maximum
is at least 100 divisions. Placing the trigger point off the screen to the
left is called Delayed Sweep.
SET TO ZERO Button. Use to set the horizontal position to zero.
SEC/DIV Knob (Horizontal Scale). Use to change the horizontal time
scale to magnify or compress the waveform.
Key Points
SEC/DIV. If waveform acquisition is stopped (using the RUN/STOP or
SINGLE SEQ button), the SEC/DIV control expands or compresses
the waveform. Use to zoom in on a detail of the waveform.
Scan Mode Display (Roll Mode). When the SEC/DIV control is set to
100 ms/div or slower and the trigger mode is set to Auto, the
oscilloscope enters the Scan acquisition mode. In this mode, the
waveform display updates from left to right. There is no trigger or
horizontal position control of waveforms during scan mode. See
page 9- - 6.
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TPS2000 Series Digital Oscilloscope User Manual