Building/testing a spark gap tesla coil

This video shows the process of building a basic spark gap tesla coil.

A tesla coil is basically a fancy transformer. You have a high voltage power supply, which charges a capacitor bank. When the capacitors have enough charge, they can dump a lot of electricity across a spark gap. When the spark gap fires, it sends a pulse into the primary coil, which creates an electromagnetic field. The secondary coil is inside the primary but is not electrically connected to it. When the primary creates an electromagnetic pulse, it induces a current into the secondary through inductance. If the two coils are tuned to the same frequency, it will boost a lot of electricity up the secondary and the secondary will release arcs into the air.

Neon sign transformers, or NSTs, are a common tesla coil power supply. They are usually between 6 and 15kv at 30 or 60ma. They work great, they’re simple, and they’re way safer than MOT’s, but should used with caution: touching one terminal will give you a nasty shock but (probably) won't kill you. touching both terminals at once can send 15,000 volts across your heart and kill you in an instant. So be careful.

WARNING: Tesla coils are dangerous. I am not responsible for anyone who damages anything or hurts or kills him or herself after attempting to recreate what is depicted in this video.