Instrumentation for Analog Differentiator at Low Frequencies
Roy Albert Chapman · Review of Scientific Instruments · 1969
Sources of errors and noise in analog differentiators are reviewed, together with techniques for minimizing signal distortion. A modified basic operational differentiator is augmented with a linear phase filter. Accurate derivatives are obtained over the range spanning dc to 1 Hz. An inexpensive instrument is presented which reduces noise to a low level while minimizing delay distortion of the signal.