Magnetic characteristics pertinent to the operation of cores in self-saturating magnetic amplifiers

A METHOD of measuring the magnetic characteristics which control the manner in which cores operate in self-saturating magnetic amplifiers is necessary for both economical production and accurate design of such amplifiers. It has been found1,2 that there is a lack of direct correlation between amplifier characteristics, such as gain, and either d-c or a-c major hysteresis loop measurements. The difficulty lies in the manner in which the time lag3 occurring between the application of a magnetizing force on a core and the resultant change in magnetic induction, affects the operation of a self-saturating amplifier. The result is that, to determine the effective magnetic characteristics of a core pertinent to self-saturating magnetic-amplifier operation, it is necessary to measure characteristics under simulated amplifier operating conditions in such a way that the effect of magnetization lag will be similar.