Scientific
SMO1000E
130/185
To display a FFT waveform:
1. Press the
Math
button on the front panel to open the MATH function menu.
2. Press the
Operation
softkey and then turn the
Universal Knob
to select
FFT
.
The resulting math waveform is displayed in white and labeled with “M”.
3. Press the
Source
softkey, and then turn the
Universal Knob
to select the source to
do FFT operation. Analog channels (CH1 and CH2) and reference waveforms
(REFA, REFB) can be used as the source.
4. Press the
Window
softkey, and then turn the
Universal Knob
to select an
appropriate window.
Spectral leakage can be considerably decreased when a window function is used.
The oscilloscope provides four kinds of FFT window functions which have different
characteristics and are applicable to measure different waveforms. You need to
select the window function according to different waveforms and their characteristics.
Please read the table below carefully to make a appropriate option according to the
input signal.
Window
Characteristics
Measurement
Rectangle
The
best
frequency Transient or short pulse, the signal
resolution;
the
poorest levels before and after the
amplitude resolution; similar multiplication are the basically the
to the situation when no
same; Sine waveform with the same
window is multiplied.
amplitude
and
rather
similar
frequencies; Wide band
random
noise with relatively slowly changing
waveform spectrum.
Hanning
Better frequency resolution; Sine, periodic and narrow band
poorer amplitude resolution.
random noise.
Hamming
A litter bit better frequency Transient or short pulse, the signal
resolution than Hanning.
levels before and after the
multiplication are rather different.
Blackman
The
best
amplitude Single frequency signal, search for
resolution;
the
poorest higher order harmonics.
frequency resolution.
5. Press the
FFT Zoom
softkey, and then turn the
Universal Knob
or turn the
horizontal scale knob to select the desired magnifying multiple (1X, 2X, 5X, 10X). Set
the
FFT
Zoom
to an appropriate magnifying multiple to observe more details of the
FFT
waveform.
6. Press the
Scale
softkey to select the unit of vertical axis. The unit of the vertical
axis can be dB or Vrms which 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, dBVrms is recommended.
Summary of Contents for SMO1000E
Page 1: ...Digital oscilloscope SMO1000E User Manual ...
Page 17: ...Scientific SMO1000E 17 185 Appearance and Dimensions Figure 1 Front View Figure 2 Top View ...
Page 54: ...Scientific SMO1000E 54 185 Figure 12 x Interpolation Figure 13 Sinx x Interpolation ...
Page 82: ...Scientific SMO1000E 82 185 Figure 28 Relative Window Trigger ...
Page 84: ...Scientific SMO1000E 84 185 Figure 29 Interval Trigger ...
Page 109: ...Scientific SMO1000E 109 185 Figure 53 UART Trigger ...