MATH Waveform
CH1+CH2
1. FFT Spectrum Analyzer
The FFT process mathematically converts a time-domain signal into its frequency
components. You can use the Math FFT mode to view the following types of signals:
●
Analyze
the Humorous wave in the Power cable.
●
Test
the Humorous content and distortion in the system
●
Show
the Noise in the DC Power supply
●
Test
the filter and pulse response in the system
●
Analyze
vibration
Table 2-9 FFT function menu 2:
Function
Setting
Introduction
Scale
Vrms
Set Vrms to be the Vertical Scale unit.
dBVrms
Set dBVrms to be the vertical Scale unit.
Display
Split
Full screen
Display FFT waveform on half screen.
Display FFT waveform on full screen.
Next Page
Page 2/2
Return the first page of FFT menu.
Table 2-8 FFT function menu 1:
Function
Setting
Introduction
Source
CH1
CH2
Select this channel as the FFT source.
Window
Hanning
Hamming
Rectangular
Blackman
Select FFT window types.
FFT ZOOM
1X
2X
5X
10X
Changes the horizontal magnification
of the FFT display.
Next Page
Page 1/2
Enter the second page of FFT menu.
To use the Math FFT mode, you need to perform the following tasks:
1. Set up the source (time-domain) waveform.
●
Press
the AUTO button to display a YT waveform.
●
Turn
the vertical POSITION knob to move the YT waveform to the center
vertically (zero divisions).
●
Turn
the horizontal POSITION knob to position the part of the YT waveform
that you want to analyze in the center eight divisions of the screen.The
oscilloscope calculates the FFT spectrum using the center 1024 points of
the time-domain waveform.
●
Turn
the Volts/div knob to ensure that the entire waveform remains on the
screen.
●
Turn
the S/div knob to provide the resolution you want in the FFT spectrum.
●
If
possible, set the oscilloscope to display many signal cycles.
To display FFT correctly, follow these steps:
●
Push
the MATH button.
●
Set
the Operation option to FFT.
●
Press
the Source button to select CH1or CH2according to input signal
channel.
●
According
to Nyquist law, turn the S/div knob to adjust the sampling
rate(This parameter is displayed behind the time base parameter) is at
least double than input signal frequency.
18
Digital
S
torage
O
scilloscope
Digital Storage Oscilloscope
19
