Tesla coils are beautiful examples of high voltage hardware, throwing sparks and teaching us about all kinds of fancy phenomena. They can also be quite intimidating to build. [William Fraser ...

Everyone interested in electronics should build at least one Tesla coil. But be careful. Sure, the high voltage can be dangerous, but the urge to build lots of coils is even worse ...

A coil of wire, or solenoid, consists of a wire coiled up into a spiral shape. When an electric current flows, the shape of the magnetic field is very similar to the field of a bar magnet.