Abstract: An X-ray thickness monitor is mounted on a moveable carriage which also supports a duty cycle sensor and a shoulder find sensor. The duty cycle sensor is aligned to scan the same portion of a terminal strip as that which passes under the X-ray beam. The duty cycle sensor is used to measure the ratio between the widths of individual terminals in the terminal strip and the period between adjacent terminals. This duty cycle is then used as a correction factor to correct the measured thickness value in order to compensate for gaps between adjacent terminals. The shoulder find sensor monitors the duty cycle at a shoulder on the terminal and moves the carriage as necessary to maintain the shoulder find sensor in position over the shoulder, thereby maintaining the X-ray beam and the duty cycle sensor in position over the crown to be measured. The X-ray monitor is automatically standardized periodically in order to ensure the accuracy of the measurement.

Abstract: Crossbar switch array employs two linear conductors having resistors thereon, with horizontal and vertical crossbar conductors connected to linear conductors between the resistors. All resistors have identical value, so that when a switch is closed, voltage readings taken at one end of each of the linear conductors permit calculation of the number of resistors passing current in each linear conductor where a constant current source is provided. An analog signal is developed which is proportional to the row and column of the closed switch.