Tektronix TPS2000 Series User Manual page 199

Reference
Window Zone. Use the Window Zone option to define a segment of a
waveform to see more detail (zoom). The Window time base setting
cannot be set slower than the Main time base setting.
Vertical bars define Window Zone
Main Window Zone
time base displayed
displayed
Window. Expands the Window Zone to cover the entire screen. Use to
change between two time bases.
NOTE. When you change between the Main, Window Zone, and
Window views, the oscilloscope erases any waveform saved on the
screen through persistence.
Holdoff. Use holdoff to help stabilize the display of complex
waveforms. Refer to Holdoff on page 9- - 46 for more information.
TPS2000 Series Digital Oscilloscope User Manual
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