Cadence Demo (OrCAD)
From CVL Wiki
Cadence's OrCAD Demo package is a SPICE tool for circuit simulation used in a number of classes. This package has a component limit (20) and a node limit (64). If you need to design a circuit with more components in it, you will need the licensed version of OrCAD.
Installing OrCAD Demo
Click here. Login with your Virginia Tech PID/password. Save the file to your desktop. This will take a few minutes to a long time depending upon the speed of your network connection. If you don't have a fast network connection at your home/apartment, it would probably be faster to go to campus and use the campus network.
Right click the ZIP file, select "Extract All...". Extract to your Desktop.