User Manual

SIGLENT
118 User Manual
Note:
 Signals with DC components or deviation would cause error or deviation of the FFT
waveform components. To reduce the DC components, set the Channel Coupling
to AC.
 To reduce the random noise and aliasing frequency components of repetitive or
single pulse, set the Acquisition of the oscilloscope to Average.
Note: please refer to the cursors chapter to obtain the method of using cursors.
7. Press the Display softkey to select Split or Full Screen display mode.
 Split: the source channel and the FFT operation results are displayed separately.
The time domain and frequency domain signals are displayed clearly
 Full Screen: the source channel and the FFT operation results are displayed in
the same window to view the frequency spectrum more clearly and to perform
more precise measurement.
Figure 43 FFT Waveform In Split Mode
To measure FFT waveform:
To make cursor measurements, press the Cursors button, and then press the Mode
softkey to select On to turn the cursors, Use the X1 and X2 cursors to measure frequency
values and the difference between two frequency values (ΔX). Use the Y1 and Y2 cursors
to measure amplitude in dB and difference in amplitude (ΔY).
You can find the frequency value at the first occurrence of the waveform maximum by
using the X at Max Y measurement.