One more link that might be of use.. Electronics for Beginners and Intermediate Electronics http://ourworld.cs.com/gknott5413/ a very large collection of information about electronics for beginning and intermediate levels. The beginners section is divided into categories consisting of general theory, practical skills and projects, components, test and measurement, digital, DC theory, and block diagrams. The intermediate area has even more information, including transistor operation and common amplifiers. This is a great site for hobbyists, too. Cheers, Ling SM -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body