FREE PCFILT may be download here:

PCFILT is now a public domain program free for use by anyone who needs to design passive filters. It no longer requires a hardware key (dongle) to operate. I request that it NOT be used to design filter to be used in military weapon systems.

NOTE: Extract the zip file into the folder C:\ (the "root" directory). The unzip process should put all files into c:\pcfilt and several folders below. Be sure that your extraction program is set to regenerate the file structure in the zip file. PCFILT can be installed in other folders, such as c:\programs\pcfilt, but it is NOT recommended.

PCFILT, Version 2.xx for 32 or 64 bit Windows

PCFILT changes list (text file) * Upgrades *

<=== When installed properly, the new folder (C:\pcfilt) should like this.

UPDATE: To update from earlier versions copy these three files from the zip file to the c:\pcfilt folder:

pcfw.exe, pcfw.hlw, hlw_ndx.dat.

PCFILT does not utilize any of the confusing facilities of Windows, such as user folders or the registry. If you choose to remove the program later simply delete the folder C:\PCFILT and all sub-folders.

Complete users guide:

The PCFILT users guide, in Acrobat (pdf) format, may also be downloaded but it is included with the program download above.

The downloadable users guide is in multiple Adobe Acrobat "pdf" format files "ZIPed" together. You must first un-zip them into a new directory (folder).

PCFILT Windows version users guide (1700Kb)

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