Discusses three types of sensors; pressure, gas detection, and relative humidity. Explains their use for laboratory measurements of gas pressure and detection of specific gaseous species. Shows diagrams of devices and circuits along with examples and applications including microcomputer interfacing. (RT)

Describes direct and indirect voltage input techniques and their applications to voltage measurements with a microcomputer. Details circuitry that can be used for this with a gameport. Gives examples of circuit modifications, application of voltage measurement, and alternatives to this method. (CW)