Abstract: An apparatus and method for sorting plastic bottles for recycling wherein if it is first determined that a bottle is clear, the bottle will be ejected. If the bottle is not determined as being clear, the apparatus or method next determines if the bottle is colored. If the bottle is colored, the bottle will be ejected. The above method may also be accomplished by use of a truth table which analyzes the characteristics of a bottle. Also provided is a detector for detecting the presence of chlorine in a plastic bottle by means of X-ray fluorescence. A sorter device sorts the bottles into small diameter and large diameter bottles.

Abstract: A macro phase detector responds to large phase deviation between a locally generated signal and a reference signal for actuating a successive frequency approximation register to effect major count alteration in a counter for controlling a digital-to-analog converter and, in turn, a voltage controlled oscillator. Small phase error is detected by a phase detector, averaged, and employed to alter the count in the counter for introducing sensitive frequency adjustment. A second counter is clocked by the phase detector at one half the rate of the first counter and is used to update the first counter each time the phase difference reverses polarity. Loss of reference signal activates a detector for freezing the count in the counter to maintain frequency and phase within the accuracy of the controlled oscillator.