Owon XDS4000 Series User Manual page 41

4.Advanced User Guidebook
Figure 4-5 Kaiser window
Figure 4-6 Bartlett window
Notes for using FFT
◼ Use the default dB scale for details of multiple frequencies, even if they have
very different amplitudes. Use the Vrms scale to compare frequencies.
◼ DC component or offset can cause incorrect magnitude values of FFT
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