Modern midrange oscilloscopes have more features than most engineers ever use. This article summarizes 10 oscilloscope applications that may surprise you. In any event, you may find them useful.
Use the oscilloscope's fast edge feature and math operations to make frequency response measurements.
Frequency response measurements require a source signal that has a flat spectrum. By utilizing the fast edge test signal of the oscilloscope as a step source, it is possible to derive the impulse response of the device under test using the scopes derivative function. This can then be applied to the FFT (Fast Fourier Transform) function to obtain the frequency response. Figure 1 shows the steps in the process for both the frequency response of the input signal and that of a 37 MHz low-pass filter.
Deriving the frequency response of a filter by applying the fast edge test signal to the filter input (upper left), taking the filter output (upper right trace), differentiating it (right center), and finally taking the average of the FFT (lower right). The spectrum on the lower left trace shows the frequency flatness of the differentiated step input.
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