R1= 56ohm 2WQ1= 2N3055R2= 330ohm Lin. pot。T1=220V@18V 1.5AC1= 2200uF 35VC2= 100uF 35VD1= 18V 1.5W zenerC3= 10uF 25VC4= 220uF 25VC5= 100nF 100VGR1= 4 X 1N4007 This circuit of power supply, are very simple in the manufacture, the finding of his materials , is very easy and cost, small. The output voltage is stabilised and is regulated in the region from 0V until + 15V dc, with biggest provided current 1 A. The regulation becomes with the R2. The Q1 of is classIC power transistor and it needs it is placed in heatsink, one and heating when it works continuously in the region of biggest current. The type of transformer is standard in the market.