WARNING!! THIS IS HIGH VOLTAGE AC. THIS CAN KILL YOU. ALTHOUGH SIMPLE.
Step 1: PARTS
1 x Ignition Coil
1 x Dimmer Switch (500+ watts)
1 x 200v 15uf Film Capacitor (DON'T USE ELECTROLYTIC)
2 x High Voltage wire
Step 2: ABOUT IGNITION COIL
The ignition coil is commonly found in vehicles to start ignition.
The ignition coil has three terminals; one positive, one negative and one high voltage output.
It would be labelled on the ignition coil and the high voltage output is the middle of the two terminals.
Step 3: Schematic
This is a very simple schematic. I cannot take credit for it. There are many tutorials out there, but I had a larger output.
Step 4: Test It Out!
This power supply can be used for Tesla coils, Jacob ladders and many other high voltage projects. You can experiment with the capacitance to get a larger output. The higher the capacitance, the higher the voltage and current. However, if you go up to 100uf, the spark would not be continuous.