Patent ID: 8428706

Claim:
A system for measuring conductance of a material sample, comprising: a coil for creating a magnetic field adjacent to a sample to be tested; an oscillator connected to the coil for applying a voltage to the coil; and an automatic gain control circuit connected to the oscillator for sensing a voltage change caused by the sample when the sample is positioned adjacent to the coil and exposed to the magnetic field; wherein the voltage change is proportional to a conductance of the sample; and wherein the system further comprises a movable housing, the coil, oscillator and automatic gain control circuit are contained within the housing such that a portion of the coil is positionable adjacent the sample to expose the sample to the magnetic field; and wherein the system further comprises an adjustment assembly connected to the movable housing to enable movement of the movable housing to adjust the position of the coil with respect to the sample along at least two mutually perpendicular axes such that multiple sample points can be measured using the coil.