User Manual

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Use math menu
2. Use math function of FFT
Successively press and to set math as FFT operation. Set Ch1 and Ch2 as
signal source, by using the FFT operation; transform the waveform from time-domain to
frequency-domain for waveform spectrum analysis. To reduce the effect of side-lobes
(leakage), it is recommended to use auto-window; This will automatically adapt the
waveform part that is analyzed to a complete number of cycles.
Select rectangular, hanning, hamming or blackmanharris window and ensure the entire
waveform amplitude remains on the screen.
Rectangular window：
Trait: best analysis for frequency resolution, but not for amplitude resolution. It is
recommended to measure transient or narrow pulse, composite sine waves which
amplitude are almost equal and their frequency are very close, or relatively slow changed
bandwidth random noise spectrum. As shown in picture 3-34.