By using the circuit you do not bother to roll up a transformer that is used to reduce voltage AC 220V to 7V ,9 V or 12V, etc. When using a large transformer we will find it hard to make transformator. by rolling hundreds or even thousands of times roll. But if you use this circuit a little just enough to roll trafo not to small, and its be relatively small. Part List : R1________________________________680K R2________________________________47K R3________________________________100R R4________________________________1K R5________________________________1R D1,D2,D3,D4,D7,D8,D9,D10__________1N4007 D5,D6_____________________________1N4148 C1________________________________2u2F 400V C2________________________________2n2 C3________________________________47uF 25V C4________________________________10n C5________________________________470uF / 16V Q1________________________________MJE13003 Q2________________________________S8050 This is construction of transformer. For the first toll 22...