Free circuit schematics - wiparat.com

This is probably the most well known flyback transformer driver circuit. It uses two 2N3055 power transistors in a push-pull oscillator configuration. The value of the resistors is not that critical. In fact you can even use a 1/2W for the 27 ohm resistor, but it may burn out if it is left to run [...]

The LM317T output current can be increased by using an additional power transistor to share a portion of the total current. The amount of current sharing is established with a resistor placed in series with the 317 input and a resistor placed in series with the emitter of the pass transistor. In the figure below, [...]