EESOF Touchstone

Thread Starter


Joined Nov 13, 2015
Anyone other than me remember the old (1980's?) DOS simulator program EESOF-Touchstone? Ran under DOS and used a hardware dongle on the parallel port for license verification. I retired 6 years ago, and up until I retired, I continued to use that program (on an old DOS computer that still had a parallel port) to design RF filters and do other RF simulations. I was getting good designs that the 'new' guys with their more modern sim programs couldn't seem to figure out. Gawd, I miss that proggy. LTSpice is nice, but it doesn't do the same job.

Anything out there for the hobbyist (read cheap or free) that is similar to Touchstone? Something without a steep learning curve that this old man might be able to master?


Joined Feb 24, 2006
If there is one out there I haven't seen it. Either the RF community lacks the altruism of Linear Technology or nobody has the stones to do a freeware version.