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1.
Acquire enough data to fill the portion of the waveform
record to the left of the trigger point. This is also called
the pre-trigger.
2.
Continue to acquire data while waiting for the trigger
condition to occur.
3.
Detect the trigger condition.
4.
Continue to acquire data until the waveform record is
full.
5.
Display the newly-acquired waveform.
Time Base:
The oscilloscope digitizes waveforms by acquiring the
value of an input signal at discrete points. The time base allows
you to control how often the values are digitized. To adjust the
time base to a horizontal scale that suits your purpose, use the
Time/div knob.
Time Domain Aliasing:
Aliasing occurs when the oscilloscope
does not sample the signal fast enough to construct an accurate
waveform record. When this happens, the oscilloscope displays a
waveform with a frequency lower than the actual input
waveform, or triggers and displays an unstable waveform.
Sampled points
Apparent low-frequency
waveform due to aliasing
Actual high-frequency waveform
Figure 3.34 – Time Domain Aliasing Illustration
Operating Instructions:
Set up Sampling Format
You can press the “Acquisition” option button or turn the “Universal” knob
to select “Sampling” mode, “Peak Detect” mode or “Average” mode.