2. Press FFT from the bottom menu.
3. Select the Source from the side
menu.
4. Press the Vertical Units key from
the side menu to select the vertical
units used.
5. Press the Window key from the side
menu and select the window type.
Hanning, Hamming, Rectangular,
and Blackman.
6. The FFT result appears. For FFT, the horizontal
scale changes from time to frequency, and the
vertical scale from voltage/current to dB/RMS.