Today younger brother generation that study same college comes to see at a house and beg to seek design good circuit and free. I advises a program TindyCAD because it drawing circuit diagrams commonly known as schematic drawings. It supports model the equipment is a lot of and still apply to PCB layout programs change the system netlist formats. Besides still be usable cooperate SPICE simulation netlists get as well. About the copyright be model freedom License LGPL be usable get freely model open source. Link : http://sourceforge.net/projects/tinycad/
