If plan institute is shown,be electronic transformation regulated power supply. This circuit uses the method of high frequency oscillation to undertake electronic transformation, use 3 end next manostat LM317 undertakes adjustable stabilized voltage. Its characteristic is: Bulk small, weight light, circuit is simple. Commutate of D4 of ～ of D1 of classics of 220V alternating voltage turns into to shed high pressure continuously. The high frequency oscillating circuit that this volts d.c. comprises by the component such as L1, L2, L3 and T1, T2 becomes high frequency pulse, those who be added in B of high frequency transformer is primary, classics transformation is in of B sub the low pressure that gets a need, mix via wave of filter of high frequency commutate again the stabilized voltage of LM317, in LM317 output end obtains stable volts d.c. .