Abstract: A capacitance-based moisture sensor may include a sleeve having an internal cavity, a container filled with soil or other material inserted into the internal cavity, and a pair of ring-shaped conductive bands around the exterior of the sleeve forming a capacitor and providing a frequency output. The rings positioned around a perimeter of the sleeve may be connected to a fixed inductor to form an oscillator with a variable frequency output. The sensor may be calibrated from the frequency output for each of a plurality of substances, measuring the volumetric water content for saturation of the material, and determining at least one fitting constant in an equation wherein volumetric water content is a function of the frequency output and a plurality of fitting constants.

Abstract: A capacitance-based moisture sensor may include a sleeve having an internal cavity, a container filled with soil or other material inserted into the internal cavity, and a pair of ring-shaped conductive bands around the exterior of the sleeve forming a capacitor and providing a frequency output. The rings positioned around a perimeter of the sleeve may be connected to a fixed inductor to form an oscillator with a variable frequency output. The sensor may be calibrated from the frequency output for each of a plurality of substances, measuring the volumetric water content for saturation of the material, and determining at least one fitting constant in an equation wherein volumetric water content is a function of the frequency output and a plurality of fitting constants.

Abstract: A seal includes a tubular body for receiving a translatable rod which extends from a cylinder through an access opening in a gas turbine engine casing. The body includes at one end thereof an integral annular land sized to surround the cylinder. At an opposite end of the body an integral grommet includes a groove extending around the perimeter thereof sized for receiving an edge of the casing defining the access opening for providing a seal therewith.