Agilent Technologies DSO-X 4022A, User Manual

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98 Agilent InfiniiVision 4000 X-Series Oscilloscopes User's Guide
4
Math Waveforms
See Also • "Units for Math Waveforms" on page 91
FFT Measurement
FFT is used to compute the fast Fourier transform using analog input
channels or a lower math function. FFT takes the digitized time record of
the specified source and transforms it to the frequency domain. When the
FFT function is selected, the FFT spectrum is plotted on the oscilloscope
display as magnitude in dBV versus frequency. The readout for the
horizontal axis changes from time to frequency (Hertz) and the vertical
readout changes from volts to dB.
Use the FFT function to find crosstalk problems, to find distortion
problems in analog waveforms caused by amplifier non- linearity, or for
adjusting analog filters.
To display a FFT waveform:
Figure 9 Integrate With Signal Offset
Integrate
with DC offset
correction