Hi Craig, My E-mail got sent out too quick so I wasn't able to finish what I was saying. The element has three ports: ----- ---> 1 -| | --> 2 ----- | 3 With port 3 as global ground. I have used the .NET and using Z11(i) and etc. to try to calculate the Leq but got the wrong values. I have also tried to do what you have suggested which I used an AC source at port 1 and use a VCVS to mirror the same source with 180 phase shift at port 2 and got the same wrong result. I am curious if the .LIN with "port" sources in the "Hspice" can do the trick. From the .LIN and get the S11,S12,S22,S21 etc and use it to transform it to Z one port Leq. Does any one know how to do that? I am new to the "port" sources and every time I try it, it failed to simulate. Thanks, Tim ____________________________________________________ Start your day with Yahoo! - make it your home page http://www.yahoo.com/r/hs ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu