R1= 56ohm 2W Q1= 2N3055 R2= 330ohm Lin. pot. T1=220V@18V 1.5A C1= 2200uF 35V C2= 100uF 35V D1= 18V 1.5W  zener C3= 10uF 25V C4= 220uF 25V C5= 100nF 100V GR1= 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.