W
AVE
R
UNNER
X
I
S
ERIES
Displaying Individual Segments
1. Touch
Math
in the menu bar, then
Math Setup...
in the drop-down menu.
2. Touch a function tab (
F1
to
Fx
The number of math traces available depends on the software options loaded
on your oscilloscope. See specifications.).
3. Touch
inside
the
Operator1
field and select
Segment
from the pop-up menu.
4. In the right-hand dialog, touch the
Select
tab.
5. Touch
inside
the
Select
field and use the pop-up numeric keypad to select the segment you want to display.
Note:
In Persistence mode, the segments are automatically overlaid one on top of the other in the display. In
non-Persistence mode, they appear separately on the grid.
Viewing Time Stamps
1. In the menu bar, touch
Timebase
, then touch
Acquisition Status...
in the drop-down menu.
2. Touch
the
Trigger time
tab.
3. Under
Time of
, select channels or a memory waveform.
RIS Sampling Mode - For Higher Sampling Rates
RIS (Random Interleaved Sampling) is an acquisition technique that allows effective sampling rates higher than
the maximum single-shot sampling rate. It is used on repetitive waveforms with a stable trigger. The maximum
effective sampling rate of 50 GS/s can be achieved with RIS by making 100 single-shot acquisitions at 500 MS/s.
The bins thus acquired are positioned approximately 20 ps apart. The process of acquiring these bins and
satisfying the time constraint is a random one. The relative time between ADC sampling instants and the event
trigger provides the necessary variation, measured by the timebase to 5 ps resolution.
The instrument requires multiple triggers to complete an acquisition. The number depends on the sample rate: the
higher the sample rate, the more triggers are required. It then interleaves these segments (see the following
figure) to provide a waveform covering a time interval that is a multiple of the maximum single-shot sampling rate.
However, the real-time interval over which the instrument collects the waveform data is much longer, and
depends on the trigger rate and the amount of interleaving required. The oscilloscope is capable of acquiring
approximately 40,000 RIS segments per second.
Note:
RIS mode is not available when the oscilloscope is operating in Fixed Sample Rate mode.
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