Hello, I want to make a phase shift but I am not able, I put Vin as one sinudoidal wave, Freq = 50Hz and Amp = 10 V and Vout as having the same wave but offset 120 degrees. So how i can do it? thank you

Thank-you. Here is a simple way to do it. It would be best to make R1, R2 and R4 variable. You may get quite a bit of variation over temperature so choose good quality capacitors and resistors.
Adam

Phi = tan^-1(XC/R) or Phi = 360*fo*dt. But this will only get you close, you will have to adjust the resistor values to get it right. When I did the calculations the circuit didn't produce the desired phase shift so I had to manually change them to get it right, you will need to adjust the values yourself.
Adam

Yes, i understant. I made a test, that is I want to offster another wave 240ºdegrees or -120º degrees, so i use as Vin the Vout of this circuit and it's ok!