The input here is 250 volt AC and the first transformer is a neon sign transformer that steps up the voltage to about 15000 volt. The resistent is ment as a spark gap. The second transformer is the large coil you can see that is on the tube or other round pipe you wind. Is steps the voltage to aubout 0.5 million volts. The last capaciteit is not really there it is just the toroid that had A very small capacitance. The oscillation is different on the tesla coil, that oscillation is much higer.
