3
Using the Scope Functions
104
Agilent U1602A/U1604A User’s and Service Guide
FFT (Fast Fourier Transform)
The FFT math function converts a time- domain waveform into
frequency- domain waveform and the magnitude of the FFT spectrum is
displayed in dBV. In other words, the readout for the horizontal axis
changes from time to frequency (Hertz) and the vertical axis changes from
volts to decibels (dB).
FFT waveforms are useful to determine the harmonic contents and
distortion in analog waveforms caused by amplifier non- linearity, for
characterizing noise in DC power supplies or to adjust analog filters.
To perform FFT measurement, follow the instructions below:
1
Press
button to access User menu.
2
Press F3 to access Math function menu.
3
In the Math submenu, press F1 to select the FFT function.
4
After selecting FFT, the submenu of the FFT function is displayed
concurrently for function properties setting.
Source
Press F2 to select the source (channel 1 or channel 2) for the FFT.
V Axis
Press F3 to select vertical scale factor expressed in dB/div. There are four
scale factors for your selection:
•
1 dB
•
2 dB
N O T E
The FFT function is only available for model U1604A.
