DGS S/FILSYN

* The industry standard for power and precision *

BIG NEWS: S/FILSYN (vs 1.70) is now public domain. It requires no hardware key and is free to download! Click on the dump-truck on the left,

Have you ever:

S/FILSYN will do all of this and more!



NOW AVAILABLE - S/FILSYN for Windows NT/XP/7/8 32 or 64 bit operating systems!

The S/Filsyn program for the synthesis, design and analysis of all kinds of electrical filters, has just been released in its first Windows version. This is a standard 32 bit Windows executable, running under any of Windows version from 95 to 8. It contains all the features of the last DOS version of the program, including all the script files as well as built-in high-resolution graphics display and print capabilities.

The program can handle passive LC, microwave, active RC, IIR and FIR digital filters. Filter types can be low-pass, linear-phase low-pass, high- pass, band-pass, band-reject filters and delay lines.

Implementations have always been one of the strong points of the program. Passive LC and microwave filters may be implemented in lattice, ladder or mixed forms. Ladders may contain bridged- or twin-T's and segments of it may be converted to lattice, cross-coupled triplets and quadruplets and other forms. Script files help in designing a very large number of band-pass filters in the form or coupled resonators. Extreme termination at one end permits the user to design components for multiplexers.

Active RC networks can be designed in cascaded second order sections, or second order sections in a leapfrog or a follow-the-leader feedback forms. Implementations may use either operational amplifiers or operational transconductance amplifiers

IIR digital filters can be implemented in cascaded second order sections, parallel, direct, Gray-Markel lattice, several wave-digital forms and differential allpass forms if applicable.

All low- and band-pass filters can be delay equalized. Many special design techniques are incorporated, including specified sloping-loss band- passes, switched-capacitor filters, Gaussian and Papoulis filters and many others.

Filters may be analyzed in the frequency and time domains, results displayed and printed. Filter data may be saved, recalled, saved in text form and transferred to other programs.


The new Windows version 1.0 menu provides for easy automatic design of virtually all of the most commonly used filter types:

Here is a typical parameter window used by the automated menu system. This one is used with the "Quasi-elliptic bandpass filters" option:

After any synthesys is complete a menu of powerfull tools are at your disposal to perform Norton Transforms and many other transformations to make the filter realizable. Everything you do is recorded allowing the scroll bar to be used to review what you have done. A large network can not scroll off the screen out of sight!

This is just the automated filters menu. S/FILSYN can be operated manually to do things that the "big name" engineering software packages can't even begin to do!

Don't let the lack of silly "eyewash" fool you. This is a serious tool for the serious filter designer!

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