High voltage applications can be found in various fields, such as ignition in internal combustion engine, gas igniter, cathode ray tube excitation, ionizer for dust odor catcher for air sanitary, ionic propulsion or many other things. The schematic diagram presented here shows a circuit of high voltage generator that can be used for various purposes. This circuit uses a 4049 hex inverter as an oscillator, and you can use ignition transformer from automotive engine. A fly-back transformer is possibly usable too. The 4049 will drive the IRF731 HEX FET. The Q1 must be heat-sinked to avoid overheating. Be careful in handling the output since this high voltage output might cause hazardous shock.