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www.tektronix.com/tds3000
TDS3000C Series Oscilloscopes
Look for Unintentional Circuit Noise
Developers need to check for unintended noise in
their prototypes. To do so, developers can use
advanced math, such as Fast Fourier Transform
(FFT) displays. The FFT feature breaks down signals
into component frequencies, which the oscilloscope
uses to display a graph of the frequency domain of
a signal, as opposed to the oscilloscope’s standard
time domain graph. Developers can then associate
those frequencies with known system frequencies,
such as system clocks, oscillators, read/write
strobes, display signals, or switching power
supplies. For example, switching power supplies
can generate odd-order harmonics, which can
enter the power grid and degrade designs. The
TDS3000C Series offers a standard FFT feature,
making it an ideal tool for these developers.
To create and run an FFT measurement:
1. Press the vertical
Math
button.
2. Press the
FFT
button.
3. Select the signal source, vertical scale, and FFT window.
4. If desired, use the
Zoom
button along with the horizontal
Position
and
Scale
controls to magnify and position the
FFT waveform.
