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AnalyzeThat.net
Offers basic electronic circuit analysis online, includes voltage, current, and power dissipation.
http://www.analyzethat.net/
Circuit Sage
Offers tools and links for analog/RF circuit design and analysis.
http://www.circuitsage.com/
DesignNotes
Contains archives, design forum, tutorials and study guides, contests, links, and more.
http://www.designnotes.com/
Ohms Law
Devoted to understanding how to work with electronic circuits.
http://www.ohmslaw.com/
Trinary.cc
Dedicated to promoting the use of trinary algebra in logic circuit design.
http://www.trinary.cc/
WebEE - The Electrical Engineering Homepage
Provides links to electronic device manufacturers, career sites, tools, and more. Posts schematics and electronic design information.
http://www.web-ee.com/