Self-compensating magnetic core magnetometer utilizing the switching time of the core as a measure of the field

Claim 1

A MAGNETOMETER COMPRISING: (A) A MAGNETIC CORE HAVING A HYSTERESIS LOOP CHARACTERISTIC PROVIDING AT LEAST TWO STABLE STATES WITH A FIXED SWITCHING TIME THEREBETWEEN, (B) MEANS BIASING THE STATIC OPERATING POINT OF SAID MAGNETIC CORE AT A PREDETERMINED REFERENCE FLUX LEVEL ON SAID HYSTERESIS LOOP INTERMEDIATE SAID STABLE STATES, (C) MEANS RESPONSIVE TO DISTURBANCES IN A MAGNETIC FIELD FOR SHIFTING SAID OPERATING POINT ON SAID HYSTERESIS LOOP AWAY FROM SAID REFERENCE FLUX LEVEL IN AMOUNT COMMENSURABLE WITH SAID DISTURBANCES THEREBY CHANGING THE TIME REQUIRED TO SWITCH SAID MAGNETIC MATERIAL INTO ONE OF ITS SAID STABLE STATES AND, (D) MEANS FOR SWITCHING SAID CORE, AND, (E) MEANS COUPLED TO SAID MAGNETIC CORE FOR DETERMINING THE TIME REQUIRED TO SWITCH SAID MAGNETIC CORE INTO ONE OF ITS SAID STABLE STATES THEREBY TO PROVIDE AN INDICATION AND MEASURE OF DISTURBANCES IN SAID MAGNETIC FIELD.