Keysight DSOX3024T - Page 109

Math Waveforms 5
Keysight InfiniiVision 3000T X-Series Oscilloscopes User's Guide 109
Use the FFT (Magnitude) 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:
1 Press the Display Math softkey and turn the Entry knob to select the math
function you want to display. Then, either push the Entry knob or press the
Display Math softkey again to display the selected math function.
2 Press the [Math] key. Then, press the Display Math softkey and select the math
function you want to use. Then, press the Operator softkey and select FFT
(Magnitude) or FFT (Phase).
• Source 1 — selects the source for the FFT.
• Span/Center or Start Freq/Stop Freq — this pair of softkeys let you define the
displayed frequency range. Press the softkeys to toggle between:
• Span/Center — Span specifies the frequency range represented by the
width of the display. Divide span by 10 to calculate the frequency scale
per division. Center specifies the frequency at the center vertical grid line
of the display.
• Start Freq/Stop Freq — Start Freq specifies the frequency at the left side of
the display. Stop Freq specifies the frequency at the right side of the
display.
To set desired values, tap the softkey label on screen for a keypad entry
dialog or turn the Entry knob.
• Scale — opens a dialog box for adjusting the math waveform's vertical scale.
• Offset — opens a dialog box for adjusting the math waveform's vertical offset.
• Bin Size, RBW (Resolution Bandwidth), Sample Rate — displays the FFT
resolution in one of three different ways.
• More FFT — displays the More FFT Settings Menu.
3 Press the More FFT softkey to display additional FFT settings.