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A miniaturized multichannel scaler instrument has been developed to address size and operational constraints for data acquisition in a portable laser-induced luminescence system. The multichannel scaling (MCS) function is implemented as a programmable application specific integrated circuit (ASIC) with standard interfaces for control and data-acquisition. The instrument is microcontroller-based with sufficient computing power for data manipulation and algorithmic processing. The unit includes electronics for laser control and amplification and pulse height discrimination of PMT pulses. Modification of the instrument should allow use in nuclear, chemical, and spectroscopy-related applications including Mossbauer experiments. Interfaces are incorporated allowing both computer-controlled and stand-alone operation. Implementation of the MCS function as an ASIC and comparison with conventional implementations are discussed. Full characterization of the MCS is presented including differential nonlinearity, bin dead time, and bandwidth measurements. >

This paper describes the development of a modular inspection system for the on-line inspection of printed-web (a continuous sheet of paper on a roll) material. Real-time inspection during the high-speed printing of high-quality, multicolor web materials can determine process deviations that could degrade product quality in time to take corrective action. This action can effectively and directly reduce spoilage within the current process and eliminate losses in subsequent processes. The system was initially developed for the U.S. Bureau of Engraving and Printing (BEP) for postage stamp production but can be adapted to almost any printed-web quality-monitoring applications.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A computer-based control system is described, wherein the nonvolatility of a hardware system is combined with the flexibility of a computer-based system by the use of nonalterable memory for program storage and alterable memory for manually entered alarm limits and channel deletions. Functional and reliability requirements are presented, and the system design which evolved to meet these requirements is described.

Application of a small digital computer to improve the operation of an automatic test system has been investigated. The test system had been designed for production testing of digital electronic circuitry, but it was being used for diagnostic testing in maintenance of electronic equipment. The objectives of using a computer as a control element were: ( 1) improved communication between the test system and its operator, and (2) a reduction in the number of system tests required for diagnostic testing. Interface circuits and operating programs were designed and built, and the test system was operated under computer control to study the practicality of improving the performance of the test system. The test system proved easier to operate when the computer teletype was used as a communication device, and a reduction of 30 per cent or more in the number of tests was achieved. Unexpectedly large amounts of computer memory were required to support the teletype communications system, and it was discovered that a careful balance must be made between message clarity and length. Interface hardware was most effective when it had the simplest form, and it was concluded that whenever a choice is possible, software rather than hardware should bemore » used to implement a control function. (auth)« less