Abstract: A buoyant cable system and method is provided with a flexible towed platform that may be deployed into the water from a submerged submarine. The flexible towed platform has a memory that returns to a selected shape after deployment. A presently preferred selected shape may have one or more curves that provide a function during towing. For instance, in one embodiment two oppositely extending curves each float and each are pressed by the water in a balanced manner to provide a stable platform for one or more antennas which can be of different types suitable for a wide band of radio frequency reception/transmission. In another embodiment, a keel may be formed from a weighted curved portion that is suitable for vertically supporting an antenna. The flexible towed material may be constructed of coil springs, shaped memory alloys, and the like.

Abstract: A buoyant cable system and method is provided with a towed platform that is flexible for deployment into the water from a submerged submarine. The towed platform has a memory that returns to a selected shape after deployment. In one embodiment the biasing member is a spring acting against and anchored to Kevlar® strands running through the blocks such that the blocks are compressed into a desired shape during operation but remain sufficiently flexible for deployment and retrieval. In another embodiment, a keel may be formed from a weighted curved portion that is suitable for vertically supporting an antenna above the surface of the water to prevent signal interference due to water washing over the towed transmission line.

Abstract: A method and apparatus for coupling a meter register to a communication device such that output data signals from the meter register can be transmitted to a remote location. The coupling arrangement includes a data transfer wire that is connected to the meter register and is inductively coupled to the communication device such that the data transfer wire does not need to be conductively connected to the communication device. During installation of the communication device, the inductive coupling between the data transfer wire and the communication device eliminates the requirement of a conductive connection.

Abstract: A bracket and method for use in mounting a transducer/antenna unit in an underground meter box of the type which contains a remote-reading water meter. The box has a peripheral ledge defining an access opening that seats a lid. The bracket comprises a pair of beams which are spaced-apart sufficient to enable the installation and support of a cap containing the antenna. A pair of right angles on the beam ends are seated between the ledge and lid to suspend the beam and therefore the antenna at a predetermined height below the lid. The height is sufficient for holding the antenna at a position which is optimum for radiating RF signals for pick up by an above-ground remote receiver.

Abstract: An air tank for a self-contained breathing apparatus that incorporates a coil antenna for use in a magneto-inductive system. The coil antenna is formed as a part of the tank. The antenna is embedded within the sidewall of the air cylinder to form the air tank. The self-contained breathing apparatus may include a magneto-inductive device operatively connected to the coil antenna for conducting magneto-inductive communications. A microphone and speaker or headset may be included to facilitate voice communications over the magneto-inductive system.

Abstract: An antenna device (10?, 10?, 10??, 10??) for seismic surveys, where the antenna (10?, 10?, 10??, 10??), when in the active position, is located by the seabed (2), and where the antenna (10?, 10?, 10??, 10??) is coupled to one end portion of at least one feed-out hollow element (12a, 12b), the opposite end portion of the feed-out hollow element (12a, 12b) being coupled to a fluid supply (14a, 14b, 16).

Abstract: A buoyant cable system and method is provided with a towed transmission line and antenna platform that may be deployed into the water from a submerged submarine so that the antenna extends above the surface of the water. The cable system preferably utilizes a flexible weighted keel formed in a section of the transmission line. A buoyant section of transmission line extends upwardly from the depth of the weighted keel to support one or more antennas above the surface of the water. In another embodiment, a plurality of weighted keels may be formed in sections of the transmission line whereby an inverted U-shaped buoyant portion extends upwardly from the depth of weighted keel to act as the support for a horizontally oriented antenna.

Abstract: A loop antenna useful, for example, in investigation of earth formations. Embodiments of the invention provide a loop antenna circuit comprising a loop antenna disposed to generate, in response to an electromagnetic wave, a pick-up signal on an output node. Loop antenna circuit further includes a tuning network coupled to the loop antenna. The tuning network is disposed to provide simultaneous tuning at a plurality of interrogation frequencies. Further embodiments include a preamplifier circuit coupled to the loop antenna. The preamplifier circuit is disposed to receive the pick-up signal on an input node and provide a high impedance load to the loop antenna for a first of the plurality of interrogation frequencies to reduce the secondary radiation from the loop antenna to below a predetermined value at the said first interrogation frequency.

Abstract: Cables that are detectable and/or identified from a distant location using detection equipment are disclosed. The cables include at least one communication element, a jacket, and at least one antenna element such as a parasitic antenna element. In one embodiment, the antenna element is at least partially formed from a conductive ink as a portion of a cable component that is generally deployed along a longitudinal direction of the cable. In use, the antenna element is capable of providing a predetermined electromagnetic signature for a predetermined frequency transmitted in its proximity, thereby indicating the location and/or identification of the cable for the craft.

Abstract: An animal training apparatus including an electrical conductor embedded within a flexible member, and a housing having a through-opening for receiving the electrical conductor therethrough. The flexible member is molded around the electrical conductor and the antenna, while the electrical conductor is positioned such that it extends into the housing through the through-opening. As a result of the molding process, the flexible member shields the housing through-opening, discouraging substances such as water from accessing the interior of the housing via the through-opening.

Abstract: An antenna for use in an automatic meter reading (AMR) module comprises a pin and a radiator. The radiator may be a disk radiator for example, that comprises an opening which may receive the pin. Desirably, the pin is affixed to the radiator at one end, and is disposed on a ground plane at the other end. The antenna may be a top loaded short monopole antenna, for example. Additionally, the antenna may be used in a module for a water meter. The pin and disk radiator may be stamped from a single sheet of material.

Abstract: The disclosure provides a resistivity tool for use in a wellbore, wherein at least two antennas are located at the same or substantially the same location of the tool. Each antenna may be configured to operate as a transmitter or receiver.

Abstract: A meter register includes a sealed register body having a face portion and a body that are coupled to form an internal cavity. The internal cavity includes a rotatble member, a power source and a visual display. A microprocessor is included that coacts with the power source and the rotatable member to determine a volume flow andlor a flow rate through the meter register. The visual display shows a volume of flew measured by the register corresponding to rotations of rotatable members. A detection switch is included for detecting tampering with said register actuating a signal when the register has been tampered with.

Abstract: An antenna for an electromagnetic tool having a longitudinal axis and a core. The antenna includes a flexible dielectric substrate flexibly conformed about the core and an electrical conductor disposed on the dielectric substrate. The electrical conductor is disposed on the substrate such that the antenna has a dipole moment having any desired direction relative to the longitudinal axis of the tool.

Abstract: Techniques for implementing antenna configurations with substantially co-located axes are disclosed. A method for constructing co-located antennas includes winding a first antenna on a support, the first antenna having a first magnetic dipole in a first orientation; and winding a second antenna on the support through a first set of openings in the support, the second antenna having a second magnetic dipole in a second orientation, wherein the first orientation is different from the second orientation, and wherein a center of the first magnetic dipole substantially co-locates with a center of the second magnetic dipole.

Abstract: Automatic Meter Reading (AMR) technology includes communication apparatus comprising a transmitter associated with an antenna wherein the transmitter is in communication with a utility meter installed in an underground enclosure. The communication apparatus includes a housing comprising a top-section and a depending base. The top-section at least partially houses the transmitter and the antenna with the depending base housing a power source operatively connected to the transmitter. The top-section is adjacent to an exterior side surface the underground enclosure. The depending base extends from the top-section, through an opening in said exterior side surface, and into the underground enclosure.

Abstract: A device for controlling steering of a towed underwater object, in particular a towed linear acoustic antenna. The device comprises a body having a longitudinal axis, the body being provided with a fastener for fastening it releasably to the towed object, and a plurality of stabilizer fins, each of which is coupled to the body and extends along an axis that is transverse to the longitudinal axis of said body, the angular position of each fin relative to the body being pivotable about its transverse axis by control, so as to modify the angles of inclination of said fins.

Abstract: An underwater communication method is provided. EM signals are transmitted via a seabed using an underwater electrically insulated magnetically coupled antenna. By making use of the low loss properties of the seabed, EM signal attenuation can be reduced and consequently the transmission range can be increased. The underwater electrically insulated magnetically coupled antenna may be located within a body of water or may be buried in the seabed.

Abstract: A system for providing the ability to obtain consumption data from a communication device used to transmit accumulated data from the meter register. The system includes a programming port formed as part of the communication device. The programming port includes the programming coil that allows the accumulation data received from the meter register to be read by an interrogation device. Further, the programming coil allows programming information to be transferred to the communication device from the interrogation device. The system can also include a reading module coupled to the programming port of the communication device through an inductive coupling. The reading module can extend through a pit lid such that the reading module can be accessed without removing the pit lid.

Abstract: A device comprising a RF transmitter, a casing for the RF transmitter and, connected to and extending from the RF transmitter, an antenna for radiating RF signals produced by the RF transmitter, the antenna comprising an elongated member having a first portion and a second portion each of which comprises a first conductor, a second conductor and an insulator between the first conductor and the second conductor, and, between the first portion and the second portion, a third portion comprising a first conductor, wherein the first conductor of each of the first portion, the second portion and the third portion is a common conductor connected to the RF transmitter and wherein the second conductor of the first portion and the second conductor of the second portion are electrically isolated from one another.

Abstract: An embedded antenna for facilitating wireless transmission of utility meter data is disclosed, where in one embodiment an RF antenna is a part of the faceplate of the utility meter. In another embodiment the utility meter faceplate is a single-layer or a multi-layer printed circuit board (PCB) with the RF antenna printed on any desired layer. Such faceplates may be labeled to be viewable from outside of the meter housing and/or have openings to accommodate visual access to an output display of the meter consumption information.

Abstract: The antenna configuration presented is an integral component of a retrofit module designed to incorporate a data telemetry transceiver within the confines of a utility meter.

Abstract: A meter register includes a register body having a rotatable drive shaft coupled thereto. A drive gear is attached to the drive shaft and at least one follower gear is rotatably attached to the register body and coupled with the drive gear. An antenna is provided that includes a first electrically conductive sheet, a second electrically conductive sheet, and an axially extending leg electrically connected to the first electrically conductive sheet and the second electrically conductive sheet. A first electrically conductive sheet is spaced an axial distance away from the second electrically conductive sheet wherein at least a portion of the register body is sandwiched between the first electrically conductive sheet and the second electrically conductive sheet. The meter register can be attached to a meter body and, further, an auxiliary antenna can be attached to the meter register. Also disclosed is a method of operation of a utility measuring system that incorporates the above-described meter register.

Abstract: The specification discloses a printed circuit board (PCB) based ferrite core antenna. The traces of PCBs form the windings for the antenna, and various layers of the PCB hold a ferrite core for the windings in place. The specification further discloses use of such PCB based ferrite core antennas in downhole electromagnetic wave resistivity tools such that azimuthally sensitivity resistivity readings may be taken, and borehole imaging can be performed, even in oil-based drilling fluids.

Abstract: This invention is a wireless communication medium processing apparatus which carries out communication with a wireless communication medium, to carry out at least one of reading and writing as to information which was stored in the wireless communication medium, and has a plurality of antenna, a transmission divider which was connected to the plurality of antennas, and a reception compositor which was connected to the plurality of antennas, and is characterized in that the transmission divider divides an inputted signal to output the plurality of antennas, and the reception compositor combines signals from the plurality of antennas and outputs it.

Abstract: An assembly and process for identifying and tracking assets, particularly tubulars, equipment, tools and/or devices. An antenna is electrically connected to a responding device, such as a radio frequency identification device, and this assembly is connected to an asset. The antenna may be positioned about the exterior and/or the interior of the asset and significantly increases the range of signals that may be received and/or broadcast by the responding device. A transceiver may accordingly be positioned a greater distance from the asset without regard to the orientation of the asset and still permit communication between the transceiver and the responding device. In this manner, information that specifically identifies the asset may be compiled in a data base so as to maintain an accurate history of the usage of such assets as tubulars, equipment, tool and/or devices.

Abstract: A water pit transponder assembly includes a housing with multiple sections including top, main and bottom sections snap latched together connected to a water meter. A circuit board transponder in the housing includes a controller, a transmitter, a receiver and tamper detection software connected to antennas. An encoder is connected to the water meter, and batteries provide power to operate the assembly. The transponder sends and receives at different frequencies through different antennas and is protected from environmental corrosion by being encapsulated in a get inside the housing.

Abstract: A method for processing magnetotelluric signals to identify subterranean deposits is provided for. The methods comprise obtaining magnetotelluric data from an area of interest. The magnetotelluric data comprises the amplitude of magnetotelluric signals recorded over time at one or more defined locations in the area of interest. The data for each location then is filtered through a set of frequency filters. The frequency filters correspond to subterranean depths over a range of interest. Amplitude peaks in the filtered data then are identified and analyzed to determine a value correlated to the resistance of the earth at each frequency and location. The resistance values are indicative of the presence or absence of deposits at the corresponding subterranean depth.

Abstract: The invention relates to antenna configurations for electromagnetic logging tools. The antennas have one or more electrical conductors disposed on a dielectric core. The conductor is formed on the core through plating or deposition processes and arranged such that the antenna has a first magnetic dipole moment substantially perpendicular to a longitudinal axis of the core. One embodiment includes an antenna adapted for mutual balancing using interleaved conductive paths or disks to alter the magnetic dipole moment to mutually balance the antenna system. The invention also relates to a method for producing such antenna structures.

Abstract: For use with an electric meter chassis having a dielectric housing protruding therefrom, a wireless communication device that permits information to be communicated to and from the electric meter and a method of manufacturing the same. In one embodiment, the device is comprised of: (1) a communication circuit within the chassis coupled to electric meter circuitry, and (2) an antenna element within the dielectric housing, the antenna element coupled to the communication circuit.

Abstract: An antenna including a feed tube with radial fins and circular plates at the ends of the tube and fins thereby forming a boundary for a plurality of resonant cavities. Curved plates, connected to the tube by switches of a switching system, partially encompass and subtend to the length of the tube. Interior to the tube, a transmission line from an end plate terminus conducts radio-frequency energy from the terminus to a hub and onto a switch of the switching system in which the switch is mechanically reactive to and actuated by a righting action of the curved plates when the curved plates encounter a sea state. When actuated, energy from the switch distributes to a proximate resonant cavity and curved plate to form a radiation pattern based on the difference in phase of the resonant cavity and curved plate.

Abstract: An antenna assembly is formed from at least one antenna and associated conductive connecting element (wires, conductive gel or liquid, etc.) mounted within a deformable membrane that allows the antenna assembly to be installed or fixed within a narrow gap or crevice, wherein the gap or crevice may be subject to harsh environmental conditions. The gap or crevice is preferably a gap or crevice in a closure. The antenna assembly typically has a low profile, and is installed either flush with or within a traffic surface or within ¼″ above the surface. The deformable membrane will yield under force, but return to its original shape once the force is removed. The deformable membrane and antenna assembly will deform to conform to the shape of a gap or crevice into which the antenna assembly is installed.

Abstract: A loop antenna useful, for example, in investigation of earth formations. Embodiments of the invention provide a loop antenna circuit comprising a loop antenna disposed to generate, in response to an electromagnetic wave, a pick-up signal on an output node. Loop antenna circuit further includes a tuning network coupled to the loop antenna. The tuning network is disposed to provide simultaneous tuning at a plurality of interrogation frequencies. Further embodiments include a preamplifier circuit coupled to the loop antenna. The preamplifier circuit is disposed to receive the pick-up signal on an input node and provide a high impedance load to the loop antenna for a first of the plurality of interrogation frequencies to reduce the secondary radiation from the loop antenna to below a predetermined value at the said first interrogation frequency.

Abstract: An antenna structure is separately and independently formed with respect to a tubular adapted for long-term disposal within a wellbore. The antenna is adapted for easy and rapid deployment on the tubular. An independently formed ‘partial ring section’ (or arcuate shaped member) contains an antenna coil. In one embodiment, one or more of the independently formed partial ring sections is placed on the exterior of the tubular to form a well completion. In another embodiment, a plurality of partial ring sections are coupled to a spooled cable for rapid deployment of the antennas onto a tubular in the field. Another embodiment includes partial ring sections forming an antenna with multiple coils of differing orientation to provide directional sensitivity.

Abstract: A compact antenna transmits and receives broadband electromagnetic energy signals over a 180° hemispherical pattern in air at the ocean's surface. The antenna has an elongate semi-cylindrical shell and a circular end disc connected to one end, and a semi-circular end disc connected to the other end to form a half-cylinder cavity. A curved plate is connected to the circular end disc and a curved body portion has a curved end extending parallel with the semi-cylindrical shell. A vertical stem has an upper portion connected to the curved plate. The semi-cylindrical shell, circular end disc, semi-circular end disc, and vertical stem are made from a material that is conductive of electromagnetic signals, and they can be differently dimensioned to change the center frequencies to embrace different broadband ranges. The antenna is deployed and retrieved from a submarine in a tow body.

Abstract: A body detecting element is buried in the ground together with a body such as a metal body and includes a magnetic member acting as a magnetic core, an antenna coil wound around the magnetic member and a capacitor connected to both the ends of the antenna coil for forming a resonance circuit together with the antenna coil. The antenna coil is mounted on the body integrally therewith through an electromagnetic shield member with the outer peripheral surface thereof confronting the outer surface of the body. A body detecting element includes an RFID circuit connected to the antenna coil and mounted on a body integrally therewith such that the outer peripheral surface of the antenna coil confronts the outer surface of the body through an electromagnetic shield member. Even if the body detecting element is mounted on the body such as the metal pipe integrally therewith, it can accurately detect the body because a resonant frequency and the Q value of the coil are not changed.

Abstract: An electromagnetic borehole telemetry system providing improved signal to noise ratio. Adaptive filters use noise channels as references to remove noise from the signal channel. Directional detectors provide a signal channel with reduced noise content and improved noise channels with reduced signal content. Directional detectors may be magnetometers aligned with the magnetic field, or antennas aligned with the electric field, of signal or noise sources. Alignment may be performed by beam steering of the outputs of a three-channel detector, which may detect both signal and noise.

Abstract: Apparatus and methodology for radio utility meter reading processing of data acquisition for use with an automatic billing system involves a utility meter transmitter antenna system installed at or near ground level. An RF utility meter communication apparatus transmits utility meter data to a remote utility meter data collection unit from an underground pit box. The pit box includes a utility meter and has a generally ground level pit lid with an opening therethrough. An antenna element has an upper member extending at least partly through such pit lid opening. A depending base of the antenna element extends from the upper element and passes through the pit lid opening into the underground pit box. The depending antenna element is capacitively coupled or provided with some other form of non-mechanical coupling to the output of an RF transmitter also included within the pit box.

Abstract: An electromagnetic wave propagation resistivity borehole logging system comprising multiple groups of electromagnetic transmitter-receiver arrays operating at three frequencies. The borehole logging tool component of the system employs eight transmitters and four receivers. The transmitters and receivers are disposed axially and symmetrically along the major axis of the tool to form four group pairs. Each group pair consists of a transmitter-receiver groups axially and symmetrically on opposing sides of a reference point on the tool. Each, transmitter-receiver group consists of one transmitter assembly and two receiver assemblies. Each transmitter-receiver group is operated at two of three operating frequencies which are 100 kHz, 400 kHz and 2 MHz. Some of the transmitter and receiver assemblies are fabricated to yield azimuthally focused resistivity measurements, and to yield vertical and horizontal resistivity in anisotropic dipping beds.

Abstract: For use with an electric meter chassis having a dielectric housing protruding therefrom, a wireless communication device that permits information to be communicated to and from the electric meter and a method of manufacturing the same. In one embodiment, the device is comprised of: (1) a communication circuit within the chassis coupled to electric meter circuitry, and (2) an antenna element within the dielectric housing, the antenna element coupled to the communication circuit.

Abstract: An antenna assembly (10) for RF communication of signals representing utility meter data. The antenna assembly (10) comprises a first conductor (30) forming at least a portion of an antenna radiating element, a second conductor (28), and a dielectric (34) disposed between the first conductor (30) and the second conductor (28), such that the first conductor (30), the second conductor (28) and the dielectric (34) form a capacitor. The antenna assembly (10) further comprises an inductance (36) in cascade with the capacitor to provide a selected L-C circuit impedance in relation to the antenna radiating element. The second conductor (28) is disposed opposite to the first conductor (30) and at least one of the first and second conductors (28, 30) is movable from a first to a second position to adjust the capacitance of the L-C circuit to a selected frequency of operation.

Abstract: A system for investigating subterranean strata. An electromagnetic field is applied using a fixed dipole antenna transmitter and this is detected using a dipole antenna receiver. The receiver is moved from one location to another in dependence upon the strength of the detected signal.

Abstract: An electromagnetic borehole telemetry system providing improved signal to noise ratio. Adaptive filters use noise channels as references to remove noise from the signal channel. Directional detectors provide a signal channel with reduced noise content and improved noise channels with reduced signal content. Directional detectors may be magnetometers aligned with the magnetic field, or antennas aligned with the electric field, of signal or noise sources. Alignment may be performed by beam steering of the outputs of a three-channel detector, which may detect both signal and noise.

Abstract: An antenna system for ground-penetrating radar use, comprising first and second co-located antenna element pairs orthogonally oriented with respect to each other. Each of the element pairs includes a transmit element and a receive element. A metallic enclosure (such as a box) shields the element pairs and is open on one side to face a structure to be probed by signals from the transmit elements. The transmit and receive elements are dimensioned, shaped and arranged (a) to achieve low mutual impedance between the elements, (b) to have high sensitivity to reflected signals received from the structure being probed; and (c) to accommodate a desired rise time of a transmit pulse. The transmit elements and receive elements preferably are electrical dipoles but they may also be magnetic dipoles such as slot antennas. When electrical dipoles are employed, they may be formed of elongated diamond-shaped conductive surfaces or be of other appropriate geometries.

Abstract: For use with an electric meter chassis having a dielectric housing protruding therefrom, an antenna for allowing electric meter circuitry within the chassis to communicate wirelessly through the dielectric housing and a method of manufacturing the same. In one embodiment, the antenna includes: (1) antenna elements, located within the dielectric housing and adapted to transmit and receive electromagnetic radiation and (2) a balance circuit, coupled to the antenna elements to cause the antenna elements to act as an antenna and couplable to an unbalanced output port of a wireless communication circuit, that balances an impedance of the unbalanced output port thereby to balance the antenna.

Abstract: A ground penetrating antenna apparatus and method are provided for locating underground objects via radar, sonar, or similar methods. The apparatus includes one or more antennas that are rotatably affixed to support extensions that also rotate, but about an axis that is different from each of the antenna axes. The apparatus includes a linear propulsion mechanism, and the support extensions may be coupled to the linear propulsion mechanism via a transmission mechanism. In one embodiment, the supporting extensions rotate at a constant rate and each antenna rotates at that same constant rate but in the opposite direction.

Abstract: Apparatus and methodology for radio utility meter reading processing of data acquisition for use with an automatic billing system involves a utility meter transmitter antenna system installed at or near ground level. An RF utility meter communication apparatus transmits utility meter data to a remote utility meter data collection unit from an underground pit box. The pit box includes a utility meter and has a generally ground level pit lid with an opening therethrough. An antenna element has an upper member extending at least partly through such pit lid opening. A depending base of the antenna element extends from the upper element and passes through the pit lid opening into the underground pit box. The depending antenna element is capacitively coupled or provided with some other form of non-mechanical coupling to the output of an RF transmitter also included within the pit box.

Abstract: An antenna extension system for extending an antenna from an underwater vehicle. The system comprises a housing disposed wholly within the vehicle and a plurality of telescopically connected tiers extendible from a base tier disposed within the housing, an innermost of the tiers being adapted to support the antenna. A cable extends from a base portion of the housing and is fixed at a distal end to the antenna. A plurality of telescopically connected fairings are extendible from the housing and are disposed around the tiers and the cable. A cap is fixed to a distal end of a distalmost of the fairings for enclosing the antenna. Extension of the telescopically connected tiers from the base tier moves the antenna from wholly inside the housing to a position extending outwardly from the vehicle, and extends the cable and fairings with the tiers.

Abstract: An antenna extension system for extending an antenna from an underwater vehicle. The system comprises a housing disposed wholly within the vehicle and a plurality of telescopically connected tiers extendible from a base tier disposed within the housing, an innermost of the tiers being adapted to support the antenna. A cable extends from a base portion of the housing and is fixed at a distal end to the antenna. A plurality of telescopically connected fairings are extendible from the housing and are disposed around the tiers and the cable. A cap is fixed to a distal end of a distalmost of the fairings for enclosing the antenna. Extension of the telescopically connected tiers from the base tier moves the antenna from wholly inside the housing to a position extending outwardly from the vehicle, and extends the cable and fairings with the tiers.

Abstract: The marker has a housing, an inner member and a tuned circuit. The housing has a spherical cavity therein. The inner member is located inside of the housing cavity and is rotatable therein. The tuned circuit has an inductance in the form of a coil as well as a capacitance. The tuned circuit is tuned to a particular frequency. A weight is coupled with the inner member and is eccentrically located within the spherical cavity. The eccentrically located weight seeks the lowest portion of the housing cavity. Thus, when the marker is manipulated so as to disorient the tuned circuit, the weight will rotate the inner member back to its stable position so as to properly orient the tuned circuit coil.