摘要 |
<p>A self-tuning coin testing apparatus having a coin sensor circuit which produces an output signal indicative of a parameter characteristic of the coins which are tested by the coin sensor and a programmed microprocessor which stores an initial acceptance limit, determines whether the output signal from the coin sensor is indicative of a valid coin, stores a signal based on the output signal for each valid coin, calculates a statistical function based on the stored signal, and finally computes and stores a new acceptance limit based on the stored signals for a predetermined number of previously accepted coins. The statistical function, is preferably weighted so that it is based upon values for only a predetermined number of the most recently accepted coins so that a recent average is maintained.</p> |