User manual

4.Advanced User Guidebook
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waveform appears on the screen.
2. Select Dual Wfm Math in the bottom menu.
3. In the right menu, select Factor1 as CH1.
4. Select Sign as + in the right menu.
5. In the right menu, select Factor2 as CH2.
6. Select Vertical in the right menu; select repeatedly to make the symbol in
front of div, turn the M knob to adjust the vertical position of Math waveform;
then select to make the symbol in front of the voltage below, turn the M knob
to adjust the voltage division of Math waveform.
Using FFT function
The FFT (fast Fourier transform) math function mathematically converts a time-domain
waveform into its frequency components. It is very useful for analyzing the input signal on
Oscilloscope. You can match these frequencies with known system frequencies, such as
system clocks, oscillators, or power supplies.
FFT function in this oscilloscope transforms 8192 data points of the time-domain signal
into its frequency components mathematically (the record length should be 10K or above).
The final frequency contains 4096 points ranging from 0Hz to Nyquist frequency.
Taking the FFT operation for example, the operation steps are as follows:
1. Press the Math button to display the math menu in the bottom. The blue M waveform
appears on the screen.
2. Select FFT in the bottom menu.
3. In the right menu, select Source as CH1.
4. Select Window in the right menu; select the proper window type in the left menu.
5. Select Format as Vrms or dB in the right menu.
6. Select Hori in the right menu; select repeatedly to make the symbol in front of Hz,
turn the M knob to adjust the horizontal position of FFT waveform; then select to
make the symbol in front of the Hz/div below, turn the M knob to adjust the time
base of FFT waveform.
7. Select Vertical in the right menu; do the same operations as above to set the vertical
position and voltage division.
To select the FFT window
■ There are 6 FFT windows. Each one has trade-offs between frequency resolution and
magnitude accuracy. What you want to measure and your source signal characteristics
help you to determine which window to use. Use the following guidelines to select the
best window.
Type Characteristics Window