OWON MSO Series User Manual
Page 39
34
Fig.5-12 Hanning window
Quick Tips
If desired, use the zoom feature to magnify the FFT waveform.
Use the default dBV RMS scale to see a detailed view of multiple frequencies, even if
they have very different amplitudes. Use the linear RMS scale to see an overall view
of how all frequencies compare to each other.
Signals that have a DC component or offset can cause incorrect FFT waveform
component magnitude values. To minimize the DC component, choose AC Coupling
on the source signal.
To reduce random noise and aliased components in repetitive or single-shot events, set
the oscilloscope acquisition mode to average.
Term interpretation
Nyquist frequency: The highest frequency that any Real Time Digital Oscilloscope can
measure is exactly half of the sampling rate under the condition of no mistakes, which is
called Nyquist frequency. If under-sampling occurs when the frequency sampled is higher
than Nyquist frequency, "False Wave" phenomenon will appear. So pay more attention to
the relation between the frequency being sampled and measured.
NOTE：
While FFT mode is turned on, DO NOT USE THESE SETTINGS:
1) Horizontal window setting.
2) Change source channel in CH1/CH2 Setup menu
3) Turn on XY Format
4) Trigger control "SET 50%"
5) Auto-scale function
.