Math FFT
118 TDS1000/2000-Series Digital Oscilloscope User Manual
Normally, the display compresses the FFT spectrum horizontally i nto
250 points, but you can use the FFT Zoom function to e xpand the
FFT spectrum to more clearly see the frequency components at each
of the 1024 data points in the FFT spectrum.
NOTE. The oscilloscopevertical response rolls off slowly above its
bandwidth (60 MHz, 100 MHz, or 200 MHz, depending on the model,
or 20 MHz when the Bandwidth Limit option is set to ON). Therefore,
the FFT spectrum can show valid frequency information higher than
the oscilloscope bandwidth. However, the magnitude information
near or above the bandwidth will not be accurate.
Displaying the FFT SpectrumPush the MATH MENUbutton to display the Math Menu. Use the
options to select the Source channel , Windowal gorithm, and FFT
Zoom factor. You can displayonly one FFT spectrum at a time.