I have to study how this circuit works for impedance measure: General Radio solution for impedance measurement.
Z_x is the unknown impedance and "Controllo Fase" is the Italian translation of "Phase control".
I've found a lot of methods on internet but nothing about this. Do you have some material about it?

Z_x is the unknown impedance and "Controllo Fase" is the Italian translation of "Phase control".
I've found a lot of methods on internet but nothing about this. Do you have some material about it?
