An Automated System for Frequency Response Measurement Based on Free Software Tools

An automated system for frequency response measurement is presented. The method is based on the Fourier analysis limited to the first harmonic. Methods for the horizontal and vertical scale choice that provide maximal resolution are described. The algorithm that processes waveform samples is described. Application of the method is illustrated in four examples, two voltage gain and two impedance frequency response measurements, covering electrical and electromechanical systems, with lumped and distributed parameters. The system is capable to reveal parasitic effects, such as equivalent series resistance of inductors and electrolytic capacitors. The system is entirely based on free software. Software that implements the method is made freely available.