EMRFD Message Archive 228

Message Date From Subject
228 2006-12-09 04:51:20 Sam Morgan QUCS Circuit modeling program
This program was mentioned on the softrock40@yahoogroups.com mailing list. It
has lots of documentations and is available for both Linux and for Windows. It's
GPL'ed software and contains schematic capture, analog and digital simulation,
strip lines, filter design, attenuator design, matching networks and probably more.


Below I quoted their answer to:
Why don't you use Spice to simulate the schematics?

There are several debatable reason for this. When looking at the Spice3f.5
source code (i.e. the last version with technical support from the University of
California) it seems like the program was made as a proof of concept rather than
a ready to use application. In fact the code is not easy to extend though
possibly reliable and tested for a great variaty of schematics. The original
Spice misses a S-parameter and harmonic balance simulation which may be
necessary for microwave engineers, thus Spice would not be an all-in-one
solution. Of cource there are trillions of derivates of the last official Spice
version extending and bug-fixing it: but which shall we use? Last but not least
the licence issue. The copyright holder for the Spice code are the Regents of
the University of California. The code comes for free but isn't in fact meant to
be re-used.

Some more restriction of Spice3f.5

* limited number of nodes and devices (student version)
* though implemented and possibly ready-to-use the integration order (for
the Gear formulae) won't exceed 2 in the transient simulation code
* there are no such components as phaseshifter, isolator, circulator,
microstrip components, etc.
* the frontend isn't as good as it could be

Hope ya'll find it of use.
GB & 73's
Sam Morgan