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Functional Description
30
4-Channel SPO Digital Oscilloscopes
Functional Description
I - VERTICAL System / MATH Fu
nction (cont’d)
2) Displaying the
FFT Spectrum
Press the «
Math »
button to display the MATH menu. Use the options to select:
the Source channel, the Window, and the FFT Zoom Factor. You can display only
one FFT spectrum at a time. You can select
″Full Screen"
or
"Split"
in the
Display
option to display the waveform and its FFT spectrum on full screen, or
the waveform and the FFT on half screen at a time.
With « Split » display and « Cursors » Off, you can display simultaneously: The
entire Waveform, a Zoom portion and the FFT spectrum.
FFT Menu: Source - Window - FFT Zoom - Scale - Display
We inject on CH1 a sine wave: frequency = 21.7MHz and amplitude=896mVpp
We will use the «
Hanning
» window to calculate the FFT, to determine the
frequency and the amplitude of the fundamental :
Using
the “X1” manual cursor we can determine the frequency (
X1=21.8MHz
)
of the fundamental