User manual

Chapter 6 MATH and Measurements RIGOL
MSO2000A/DS2000A Users Guide 6-7
Note: In FFT mode and when MATH is the active channel, you can also press
HORIZONTAL
SCALE to switch between “Split” and “Full Screen”.
4. Set Horizontal Position and Horizontal Scale
The horizontal axis of the FFT operation results represents frequency and its unit
is Hz. Use HORIZONTAL
POSITION and HORIZONTAL SCALE to
set the horizontal position and horizontal scale of the FFT frequency domain
waveform respectively.
Note: Setting the horizontal position can changing the center frequency of the
FFT operation results indirectly.
5. Set the Vertical Unit
Press Scale to set the vertical unit to dB or Vrms and the default is dB. dB and
Vrms use logarithmic mode and linear mode to display vertical amplitude
respectively. If you need to display the FFT frequency spectrum in a relatively
larger dynamic range, dB is recommended.
6. Set Vertical Position and Vertical Scale
Press
and and use to set the vertical offset and vertical scale of
the FFT frequency domain waveform respectively.
7. Anti-Aliasing
Press Scale to enable or disable the anti-aliasing function.
8. Label
Press Label to define a label for the operation results. For the details, please
refer to
MATH Label.
Tips
Signals with DC components or deviation would cause error or deviation of
the FFT waveform components. To reduce the DC components, set the
Channel Couplingto AC.
To reduce the random noise and aliasing frequency components of repetitive
or single pulse, set the Acquisition Mode
of the oscilloscope to Average.