Manual

Functional description
46 Two-channel digital Oscilloscopes
Functional description
IV - ACQUISITION system (cont'd)
Time base
The oscilloscope digitizes the traces through the acquisition of an input signal at
precise points. The time base is used to control the trace sampling rate.
Use the "S/div" knob to adjust the time base coefficient scale that suits you.
Undersampling
Aliasing occurs when the sampling rate of the oscilloscope is not fast enough to
reconstruct a trace precisely. When this happens, the oscilloscope displays a
signal having a lower frequency than the input signal, or displays an unstable
signal.
Sampled points
Apparent low-frequency
waveform due to aliasing
Actual high-frequency waveform
Steps
Configure the sampling format
Press the "Acquisition" key or turn the "Adjust" knob and choose one of the
following sampling modes: "Sample", "Peak Detection", or "Averaging".
Configure the averaging
If you choose the "Averaging" mode, you can use the "Mean" button and
choose "4", "16", "32", "64", "128" or "256".
Configure the interpolation function
Press the "Sinx/x key" to choose Sinx or interpolation x.
"Sinx" corresponds to sinusoidal interpolation:
True high-frequency signal
Low-frequency signal displayed
resulting from aliasing
Sampling points