UNI-T UPO2000CS Series, Руководство пользователя

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UPO2000CS series User Manual
54
Press MATH button, then press F1 to select FFT to enter the FFT menu.
Functions Options Descriptions
Type FFT
Source
CH1, CH2, CH3,
CH4
Set any one of the CH1~CH4 for FFT source
Window
Hamming Use Hamming Window Function
Blackman Use Blackman Window Function
Rectangle Use Rectangle Window Function
Hanning Use Hanning Window Function
Vertical
Unit
Vrms
、
dBVrms Set vertical unit as linear or dB (log)
FFT Tips
Signals with DC components might cause mistakes or inaccuracies in FFT calculation. In order to reduce error, it is adviced to set the channel
to AC.
In order to reduce interference or noise from isolated events, the capture mode can be set to average.
(1) Select Window Function
UPO2000CS series provides 4 kinds of common window functions:
● Rectangle
：
The best frequency resolution is similar to the one with no window:
It is best suitable for transient or short pulses
● Hanning
：
Compared with the rectangular window, it has better frequency resolution, but less range. It is suitable
for measuring sine, periodic and narrow-band random noise.
● Hamming
：
Slightly better in the frequency resolution than the Hanning window, suitable for measuring transient or