Abstract: An inductor for use as a passive electronic component. The inductor has a hollow ceramic tube, a metal target rod located inside the hollow ceramic tube, a coil wound on the outside of the hollow ceramic tube and including a first end and a second end, and a first terminal engaging the first end of the coil and a second terminal engaging the second end of the coil. The metal target rod is fixed relative to the coil at a position so that the inductor has a zero temperature coefficient. Also provided is an LC resonant circuit including the inductor.

Abstract: A sensing apparatus for use in harsh environments to measure a target characteristic. The apparatus has a sensing element formed as a section of a coupled slow-wave structure including at least two impedance conductors each curled into a helix with opposing directions of winding around a dielectric base to form a resonator. The sensing element provides as an output signal a digital frequency that depends on the value of the measured characteristic. A target tube moves over the sensing element, covering and uncovering portions of the sensing element. An electronics module receives the output signal and displays the measured characteristic. A separate coaxial cable is connected to each impedance conductor on one end and to the electronics module on the other end, with the length of the coaxial cables separating the electronics module from the sensing element by a distance sufficient to avoid exposing the electronics module to the harsh environments.

Abstract: A sensing apparatus that measures a target characteristic. The apparatus has a sensing element formed as a section of a coupled slow-wave structure including a hollow ceramic tube and at least two impedance conductors each curled into a helix with opposing directions of winding around the tube to form a resonator. The sensing element is connected by coaxial cables to a remote electronics module which includes electronic components to create a resonant circuit with the sensing element. A metal internal target rod is configured to move into and out of the sensing element, being covered and uncovered by portions of the sensing element. This will cause the frequency of the resonant circuit to change proportionally to the movement of the target rod. The length of the coaxial cables separates the electronics module from the sensing element by a distance sufficient to avoid exposing the electronics module to harsh environments.

Abstract: A sensing apparatus for use in harsh environments to measure a target characteristic. The apparatus has a sensing element formed as a section of a coupled slow-wave structure including at least two impedance conductors each curled into a helix with opposing directions of winding around a dielectric base to form a resonator. The sensing element provides as an output signal a digital frequency that depends on the value of the measured characteristic. A target tube moves over the sensing element, covering and uncovering portions of the sensing element. An electronics module receives the output signal and displays the measured characteristic. A separate coaxial cable is connected to each impedance conductor on one end and to the electronics module on the other end, with the length of the coaxial cables separating the electronics module from the sensing element by a distance sufficient to avoid exposing the electronics module to the harsh environments.

Abstract: A wrist and arm pad for use with keyboards is disclosed. The pad has a support means which is adjustable perpendicularly with respect to the keyboard for accommodating varying anatomies and preferences. The pad is also movable horizontally with respect to the keyboard, allowing the user to access all of the keyboard without removing wrists from the support. A preferred pad has a base with rollers and anti-skid pads, a movable support means lying on the base, and a flexible overlay peripherally attached to the base and enveloping the support means. Handles attached to the support means extend out of apertures in the envelope for adjustment. A frame is provided for holding the overlay to the base, and massage dots can be provided on the upper surface of the overlay. A platform plate and clamp are provided for extension of the work surface for attaching or placing of the wrist pad assembly.

Abstract: A method and apparatus for nuclear logging, and in particular, neutron porosity logging is presented. In accordance with the present invention, a pair of spaced lithium detectors, preferably Li.sup.6 I crystal or Li.sup.6 doped glass are used to detect neutrons emitted from a borehole formation being logged. In addition, novel data processing is used to strip the gamma-ray peak from the spectrum developed by the lithium detectors.