User`s guide

2 Initial Setup
68 InfiniiVision Oscilloscopes User’s Guide
Roll mode
• Press the [Menu/Zoom] key (or [Main/Delayed] key on some oscilloscopes), then
press the XY or Roll softkey to select “Roll”.
• Roll mode causes the waveform to move slowly across the screen from right to left. It
only operates on time base settings of 500 ms/div and slower. If the current time base
setting is faster than the 500 ms/div limit, it will be set to 500 ms/div when Roll mode
is entered.
• In Normal horizontal mode, signal events occurring before the trigger are plotted to
the left of the trigger point (t) and signal events after the trigger plotted to the right of
the trigger point.
• In Roll mode there is no trigger. The fixed 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 pause the display in Roll mode press the [Single] key. To clear the
display and restart an acquisition in Roll mode, press the [Single] key again.
Use Roll mode on low-frequency waveforms to yield a display much like a strip chart
recorder. It allows the waveform to roll across the display.
XY mode
XY mode changes the display from a volts-versus-time display to a volts-versus-volts
display. The time base is turned off. Channel 1 amplitude is plotted on the X-axis and
Channel 2 amplitude is plotted on the Y-axis.
You can use XY mode to compare frequency and phase relationships between two
signals. XY mode can also be used with transducers to display strain versus
displacement, flow versus pressure, volts versus current, or voltage versus frequency.
Use the cursors to make measurements on XY mode waveforms.
For more information about using XY mode for measurements, refer to “XY Horizontal
Mode” on page 220.