Here the +50V / 3A Stabilized and Regulated Power Supply. schematic diagram: component parts list: R1= 10Kohm R2= 1 ohm 5W R3= 3.9 ohms 1W R4= 6.8Kohm 1W R5= 390 ohms 1W R6= 100Kohm 0.5W R7= 1.2Kohm 1W R8= 1.8Kohm 0.5W R9= 3.3Kohm 0.5W RV1= 470 ohms pot. Q3= BC303 or BC461 D1....4= Bridge 15A D5= LED RED 5mm C1-2-4= 4700uF 100V C3-5= 100nF 250V MKT D6-7= 10V 1W Zener D8-9-10= IN4007 Q1= 2N3055 on heatsink T1= 230Vac / 55V 3A Q2= BD162 or BD243 or BD543 Note: It 's a circuit that can give in his exit + 40V until + 60V 3A, with simultaneous stabilization. The materials that use is very simple and will not exist difficulties in the manufacture, is enough you are careful certain points: For output voltages smaller of + 50V until + 40V, the Q1 is hot enough, so that it needs one big heatsink. For output voltages bigger of + 50V up to + 70V, the stabilization is not satisfactory. Conclusion: ideal output voltage is + 45V until + 60V. In the circuit potensiometer RV