Flyback 10KV-30KV Circuit

The primary is a handwound coil wound on the opposite side of the secondary consisting of ten turns of 16 guage solid wire. The feedback winding is wound on top of the primary winding with four turns of 22 guage solid wire. Both windings are center tapped. If there is no high voltage from the secondary winding then try reversing the leads that go to the bases on the transistor. These must be in phase for proper operation. The 2N3055s can be replaced with about any large horizontal output transistor, in fact this is actually better. You can also use a PNP transistor, just reverse the polarity of the input.