High-speed Bode- and Nichols-diagram plotter

A Bode- or Nichols-diagram plotter with a new type of rectifying and filtering system is proposed. From the performance point of view, this system can be compared with a standard-type plotter operating with a `self-adapting¿ time constant. The advantage of the design is that a high-speed detection is no longer dependent on the filtering time constant. A quadratic sweeping waveform optimises the plotter display time.