Rigol DS6000 Series User Manual page 143

6 To Make Measurements
select the window function according to different waveforms and characteristics.
Press Window to select the desired window function and the default is
"Rectangle".
Table 6-1 Window Function
Window
Rectangle
Hanning
Hamming
Blackman
3. Set the Display Mode
Press Display to select "Split" (default) or "Full Screen" display mode.
Split: the source channel waveform and the FFT operation results are displayed
separately. The time domain and frequency domain signals are straightforward.
Full Screen: the source channel waveform and the FFT operation results are
displayed in the same window to view the frequency spectrum more clearly and
to perform more precise measurement.
Note: In FFT mode and when MATH is the active channel, you can also press
HORIZONTAL
4. Set the Horizontal Scale and Horizontal Position
In FFT measurement, the unit of the horizontal axis changes from Time to
DS6000 User's Guide
Characteristics
The best frequency
resolution
The poorest
amplitude resolution
Similar to the
situation when no
window is multiplied
Better frequency
resolution
poorer amplitude
resolution
A little bit better
frequency resolution
than Hanning
The best amplitude
resolution
The poorest
frequency resolution
SCALE to switch to "Split" or "Full Screen".
Waveforms Suitable for
Measurement
Transient or short pulse, the signal levels
before and after the multiplication are
basically the same;
Sine waveforms with the same amplitude
and rather similar frequencies;
Wide band random noise with relatively
slowly changing waveform spectrum.
Sine, periodic and narrow band random
noise.
Transient or short pulse, the signal levels
before and after the multiplication are
rather different.
Single frequency signal, search for
higher order harmonics.
RIGOL
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