LeCroy Digital Oscilloscopes, Руководство пользователя

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The DSO’s fidelity in reconstructing the input signal is mainly affected
by these three parameters (by others, too). The bandwidth must be
sufficient to allow all the signal components to pass through the
signal-conditioning system. And the sample rate has to be high
enough to provide a good definition of the signal. Long memory
maintains the sample rate for large time windows.
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In addition to the primary specifications described above, capture
techniques, trigger system, number of channels, availability and type
of probes, and ADC specification all impact the usability and
performance of the DSO.
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Single-shot acquisition is the DSO’s basic acquisition technique,
which makes the instrument very suitable for the study of signal
phenomena that have a low-repetition rate or are not repeated —
hence
single- shot. The timebase sweeps and stops at a time after
receiving the trigger signal defined by the user. The captured input
data signal is transferred to memory for viewing, measurement and
analysis.
The DSO may also employ a technique called Random Interleaved
Sampling (RIS) to increase its effective sampling rate in viewing
repetitive signals. LeCroy’s high-performance model has a maximum
rate of 10 giga-samples per second.
For slower timebases, there exists Roll Mode, where the signal
being acquired can be displayed in real time while being captured in
memory, scrolling as on a strip-chart recorder.
Because digital scopes acquire input signals by sampling, they can
miss glitches at the lower sample rates. But LeCroy’s Peak Detect
System captures glitches occurring between these samples. When
the system is activated, the scope samples at a very fast rate,
continuously checking for glitches using a built-in algorithm.
Meanwhile, it displays information in accordance with the sweep rate
actually set. When a glitch is detected, the scope will display it as a
thin spike on the displayed waveform.
Another of the LeCroy scope’s methods for acquiring signals is
Sequence Mode, which captures individually multiple trigger events