This java applet is an electronic circuit simulator.  When the applet starts up you will see an animated schematic of a simple LRC circuit. The green color indicates positive voltage.  The gray color indicates ground.  A red color indicates negative voltage.  The moving yellow dots indicate current.

To turn a switch on or off, just click on it.  If you move the mouse over any component of the circuit, you will see a short description of that component and its current state in the lower right corner of the window.  To modify a component, move the mouse over it, click the right mouse button (or control-click if you have a Mac) and select “Edit”.

The "Circuits" menu contains a lot of sample circuits for you to try.

If you don't have Java, get the Java plug-in.

Directions.

Index of Circuit Examples.

More applets.

Zip archive of this applet. (double-click on circuit.jar to run)

The source.

Version 1.5i, posted 2/23/10; fix mislabeled switches

Thanks to J. Mike Rollins for the Zener diode code. Thanks to Julius Schmidt for the spark gap code and some examples. Thanks to Dustin Soodak for help with the user interface improvements.