The Swift Turbidity Marker is an optical instrument developed to measure the level of water turbidity. The components and configuration selected for the system are based on common turbidity meter design concepts but use a simplified methodology to produce rapid turbidity measurements. This work is aimed at high school physics students and is the…

Reviews the potential of a data acquisition system for illustrating the nature and significance of ideas in digital signal processing. Focuses on the fast Fourier transform and the utility of its two-channel format, emphasizing cross-correlation and its two-microphone technique of acoustic intensity measurement. Includes programing format. (ML)

Discusses the use of an external analog-digital converter to use a computer as a storage oscilloscope. Provides program listings for use as a unipolar or bipolar voltmeter and storage oscilloscope. Schematics and component list are included. (JM)

Describes: (1) the structure of a data transmission source, carrier, and receiver; (2) a quantitative measure for the amount of data, followed by some quantitative examples of data transmission processes; (3) the concept of data current; (4) data containers; and (5) how this information can be used to structure physics courses. (JN)

Discusses how the British Post Office is using the Prestel information retrieval system. The information structure adopted for the Prestel databases and how the Prestel system hardware works are presented. Computer system software, types of information, and the impact of Prestel system on society are also presented. (HM)