Fft Spectral Analysis - UNI-T UTD2000 Series User Manual

After pressing theMATH button at the menu area to active mathematic operation.
Table 2-2：Math Menu
Function Menu
Type
Source1
Operator
Source2

2.7 FFT spectral analysis

By pressing F1 button again at mathematical operation mode to enter FFT (fast
fourier transform) operation, the time domain (YT) signal can be converted into frequency
domain signal.
At FFT operation, it is convenient to observe signals of the following types:
● Measure harmonic content and distortion in the system
● Display noise characteristic in DC power supply
● Analyze vibration
Table 2-3：FFT Menu Description
Function Menu
Type
Source
Window
Vertical unit
Select FFT window
Assuming that YT waveform is continuously repeated, DSO shall conduct FFT
conversion for time record with finite length. In this case, when the cycle is an integer, YT
waveforms are of the same amplitude at the starting and ending positions, without
interrupting. However, if the cycle of YT waveform is not an integer, the waveform
UTD2000 Series User Manual
Setting Description
Math Mathematic operation (+、–、×、÷)
CH1
You can select signal source1 as CH1
or CH2
CH2
+ Source1+Source2
– Source1–Source2
× Source1×Source2
÷ Source1÷Source2
CH1 You can select signal source2 as CH1
or CH2
CH2
Setting Description
FFT FFT mathematical operation
CH1
You can select signal source as
CH1 or CH2
CH2
Hanning
Set to select Hanning, Hamming,
Hamming
Blackman, or Rectangle window
Blackman
function
Rectangle
Vrms
Set vertical units as Vrms or
dBVrms
dBVrms
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