Analysis of magnetization curve and hysteresis loop error of ferromagnetic materials
Ring magnet should be soft magnetic material ring {} on the winding, and is formed by the capacitive discharge current rise curve, peak immediately removed capacitance, can be observed on the oscilloscope picture of hysteresis loop.
Hysteresis loop measurements require linear Holzer components.
A few such tests can be required to achieve satisfactory results, sometimes because the time constant is wrong and cannot be observed.