Method and apparatus for currency acceptance and slug or counterfeit rejection

A method of operating a money validation system having at least two sensors and a processing and control circuit, comprising:

• defining an activity vector originating at the zero electrical activity point and terminating at an idle operating point for the system;
• sensing data with each sensor representative of at least two characteristics of each of a plurality of genuine money items;
• combining the sensed data into a plurality of acceptance vectors;
• mapping the acceptance vectors onto a coordinate system;
• defining a mean vector having its origin at the idle operating point and terminating at the center of the mapped region;
• defining a tolerance value for the mean vector;
• generating an acceptance region based on the tolerance value and the mean vector;
• sensing an inserted item and generating data representative of said at least two characteristics;
• converting the generated data of the inserted item into a test vector;
• comparing the test vector to the acceptance region;
• and
• accepting the item as a genuine item if the test vector falls within the acceptance region.