NOTE: This is a hosting of the works of A.J. Fisher who died on February 29 2000.
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Proportional-Integral Filters


To be written


To be written

Sample rate (samples per second):
Time constant ``tau2'' (seconds):

By default, the filter is designed by the bilinear transform method, which is recommended for most applications. Tick (check) here: and the matched z-transform will be used instead. Warning: inspect the frequency response carefully if you use this option. Click here for further information about the matched z-transform, and about Bessel filters in particular.

By default, the frequency response graph has a linear magnitude scale. If that is what you want, leave the following box blank. If you want a logarithmic magnitude scale in dB, enter the lower limit of the magnitude scale in dB here (e.g. -80).
Lower limit (dB), or blank for linear scale:

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