May 01, 2012, 08:14 AM
Since most modern coins are made of Ni, and Cu or Zn, how does the detector know to show it as a .05, .10, .25 since they all have similar make-ups. And why is it that Au and Al are in the same range? With Ag I just firured it will peg out on the silver range which is also in the quarter, dollar, and 2 dollar range. Tired of pulling pull tabs there has to be a better was to differentiate the metals when you scan them. If there is a thread on this already I must have missed but some info would be appriciated.
May 01, 2012 08:14 AM
May 01, 2012, 08:46 AM
LRL fraud debunked
The metal detector doesn't know anything specific about the metallic composition of the target. It measures basically two things: the inductance (related to the size and shape), and the resistance (related to size, shape, and resistivity of the alloy in question). Clad and silver quarters are the same size and shape and the resistivity of the alloy composition is in the same ballpark. So when the machine sees something with that set of electrical properties, it calls it a quarter. Anything with similar ratio of inductance to resistance (i.e., "phase") will also be called a quarter.
Ferrous metals represent a special case because they introduce a third variable, magnetic permeability, which throws off the inductance and resistance measurements.