Two-Ports (VIERPOL.EXE) is a program for analysing linear two-ports. It can transform
S-parameters, Y-parameters, H-parameters and many others. Also it calculates figures
like MAG, stability factor and so on. You can specify the two-port parameters
either by hand are using a SuperCompact or Touchstone file. The syntax is a little bit
easier so look at BFR96.SPM for an example (note that there is only one comment line at the
beginning and you specify the parameters by magnitude and phase). To load a file simple drag
it over VIERPOL.EXE in the Explorer.

Two-Ports is an integral part of ELEKTA Professional, which is a knowledge
based system for electronics. It offers for more than any book, e.g. many tutorials,
powerful programs, many simulation examples and much more. For more information
look at the NOBLE Publishing web page http://www.noblepub.com/Crestone/elekta.html

The normal price of ELEKTA Professional is $99 and it includes this Active Filters tool
and over 30 others, e.g. for the design of RC filters, matching networks, op-amp and transistor
circuits, for creating simulation models, etc.