Operating Principle And Theory - Exploranium KT-9 User Manual

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Operating principle and Theory

Operating principle and Theory
Theory
Magnetic susceptibility is defined as the degree to which a
substance can be magnetized. In mathematical terms, this the
ratio of the intensity of the magnetization I to the magnetic
K
field H that is responsible for the magnetization, i.e.
From Ampere's law, it is known that a current (i.e. a moving
electrical charge) generates a magnetic field. The inverse
corollary to this is that a magnetic field can also influence a
moving electrical charge. Therefore, put in simple terms, an
oscillating EM field will be influenced to varying degrees by
magnetically susceptible material.
Operating principle
The KT-9 uses a 10 kHz LC oscillator and an inductive coil to
measure the susceptibility. The sequence required to obtain a
measurement of susceptibility is:
1. The frequency of the oscillator is measured in free space.
2. The oscillator frequency is next measured when the coil is
placed on the material for which the susceptibility is
required.
3. The frequency difference is directly proportional to the
materials susceptibility.
4. The susceptibility is calculated from this frequency difference
and takes into account geometric corrections to determine
the true susceptibility.
kH = I