High Voltage Power Supply

In common with many circuits, a Tesla coil requires a power supply, but not many need upwards of 7kVAC!

A commonly used source for such a high voltage is a neon sign transformer (NST). It takes in 240VAC (or your local equivalent) and transforms it up to voltages around 6 to 12kVAC. The transformer core is specifically designed to limit the output current to a maximum safe level, should the terminals become shorted. When I say safe I mean it will not cause the unit to overheat and catch fire; careless handling will still prove fatal!

For my first coil I am using a 1kW NST, as shown below. It stands about 22cm tall and is quite heavy. It came from the one local sign shop which catered for neon signs. Check out the fun to be had making a Jacob's Ladder!

* After frying the NST during a max performance run, I ordered a replacement unit directly from 'Tunewell'. They were very helpfull and happy to take one off orders from members of the public. I did not mention the use I was putting it to; no reason to alarm them!