The effective feedback factor of self-balancing magnetic amplifiers

The effective feedback factor of a magnetic amplifier is a measure for the stability of operation (drift). In conventional forms of external-feedback or self-saturating circuits, the drift is linearly proportional to the actual value of ampere-turn gain. In these circuits, the drift can be reduced by reducing the extrinsic-feedback factor. However, because the ratio of gain reduction over drift reduction is constant, the gain will be reduced at the same rate.