UTD2000 Series User Manual 
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2.6 Unit 
Press UNIT to set the unit as “V” or “A”, the default unit is V. After the unit is set, the unit 
on channel status tag will change accordingly. 
 
2.7 Mathematical operation function 
Display results of CH1 & CH2 waveform mathematic operation (+、–、×、÷). 
 
Figure 2-10 Math Operation 
 
Table 2-3:Math Menu 
Mathematic operation (+、–、×、÷) 
You can select signal source1 as CH1   
You can select signal source2 as CH2   
You can select signal source1 as CH1 
You can select signal source2 as CH2 
 
2.8 FFT spectral analysis 
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 2-4:FFT Menu Description 
FFT mathematical operation 
You  can  select  signal  source  as