User Manual

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Notes for FFT use
 The waveform zoom function also works for FFT.
 Use the dBV RMS scale for a detailed view of multiple frequencies, even if they have different amplitudes.
Use the linear RMS scale to compare all frequencies in an overall view.
 Signals that contain a DC component or offset can lead to incorrect FFT signal amplitude values. To
minimise the DC component for the source signal, select AC coupling.
 To reduce noise and aliasing in repetitive or single measurement waveforms, set the oscilloscope's
acquisition mode to average.
Nyquist frequency: The highest frequency that an oscilloscope that digitises in real time can measure is
equal to half the sampling rate and is called the Nyquist frequency. If not enough sampling points are acquired
and the frequency is higher than the Nyquist frequency, the phenomenon of the "false waveform" occurs.
Therefore, pay more attention to the relationship between the sampled and measured frequency.
Using VERTICAL POSITION and VOLTS/DIV knobs
1. Use the VERTICAL POSITION knob to change the vertical position of the waveforms of all channels
(including those created by mathematical calculation).
The resolution of this adjustment knob changes with the vertical division.
2. Use the VOLTS/DIV adjustment knob to set the vertical resolution of the waveforms of all channels
(including those created by mathematical calculation), which determines the sensitivity of the vertical
division in the order 1-2-5. The vertical sensitivity increases when you turn the adjustment knob clockwise
and decreases when you turn it counterclockwise.