Audioguru, My new measurements: C1 + 33V Pin 4 U3 -5,7v Pin 4 U2 -5,7v Pin 6 U6 8,1v Pin 6 U2 5,1v - 8,0 voltage pot down then up. LED always on Output voltage 25,4v - 32,4v The only thing that I changed on the project is the R7 with 470 ohm instead of 0,47 ohm, I will try to find the right one Thanks in advance!