Acquisition Mode - UNI-T UPO3000E Series User Manual

2. Waveform aliasing: Since the sampling rate is less than 2 times of the
actual signal frequency (Nyquist Frequency), the frequency of the reconstructed
signal will be less than the actual signal frequency.
3. Waveform leakage: Due to low sampling rate, the reconstructed waveform
might not reflect the entire actual signal.

4.2 Acquisition Mode

To obtain a waveform from sampling points, press ACQUIRE
mode to
switch between the acquisition methods.
(1) Normal Sampling
In this acquisition mode, the oscilloscope samples the signal at equal intervals
and reconstruct the waveform. For most waveforms, the use of this mode
can produce the best display.
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(2) Peak Sampling
In this acquisition mode, the maximum and minimum values of the input
signal are found at each sampling interval, and the waveform is displayed
using these values. This way, the oscilloscope can acquire and display a
narrow pulse, otherwise the narrow pulse might be missed in the normal
sampling mode. Noise might be enlarged in this mode.
(3) High Resolution
In this acquisition mode, the oscilloscope averages the neighboring points
of the sampled waveform, which can reduce the random noise on the input
signal and produce a smoother waveform on the screen.
(4) Envelope
Acquires multiple waveforms, and calculates and displays the maximum
and minimum values for all sampling points that are at the same time relative
to the trigger points. The general envelope mode uses the peak detection
mode for each individual acquisition.
(5) Average
In this acquisition mode, the oscilloscope acquires several waveforms and
finds the average, and displays the final waveform. This method can reduce
Pulse disappear
the random noise.
Observe the waveform changes by changing the acquisition mode settings.
If the signal contains a large noise, the sample waveforms without average
or with 32 times average are displayed below for comparison.
acquisition
Waveform without average
Note: Average and high resolution use different average methods. The
former is "multiple sampling average", the latter is "single sampling average".
Waveform with 32 times average