Abstract: A magnetic detector instrument includes an elongate circuit board and a magnetic sensor assembly which slides into a slot in one end of the board with edge portions of the board defining the slot being received in opposed elongate grooves formed in the sensor assembly. Also, a fitting for retaining the board while it is rotated in order to set the alignment of the sensor core includes elongate brackets with opposed grooves into which the circuit board slides.

Abstract: A structure is disclosed for mounting separate magnetic sensor assemblies in a magnetometer and the like with the axes of the respective assemblies disposed in mutually orthogonal planes. In a preferred form, the structure comprises three separate elongated housings of rectangular cross section for carrying three separate sensor assemblies. The housings are connected together so that two housings cross one another at right angles and are centered lengthwise with respect to one another. The third housing is connected to one of the first or second housings with its axis disposed at right angles to each and being centered lengthwise with respect to each. Also disclosed is a suspension assembly for suspending the structure in an outer casing, the suspension assembly including a gimbal arrangement whereby the structure is free to swing about a pair of mutually perpendicular gimbal axes.

Abstract: A magnetic sensor assembly including an elongated support is supported in a tubular housing by a pair of tapered foam sleeves that space the support from the inner surface of the housing and that resist movement of the assembly in the housing in a direction opposite to the direction of insertion of the assembly into the housing. The sleeves, which are either continuous hollow cylinders or are formed of wound strips, are attached to the support by adhesive tape at the leading end of each sleeve.

Abstract: A magnetic locator employs a loudspeaker to produce an audible signal which indicates detection of a magnetic object. The loudspeaker is mounted on a frame in a housing and is spring biased against an end wall of a cover part of the housing. Openings through the housing wall for passage of sound are protected by a shield which, together with a plateau on the exterior of the housing wall, provides an annular space for omnidirectional radiation of acoustic energy. Mounting screws for the loudspeaker project from the frame through holes in the housing wall and receive nuts for securing the cover part of the housing to the frame. When the cover part is secured to the frame, elastomeric washers on the screws inside the housing are positioned automatically, and biasing springs on the screws are partially compressed.

Abstract: A holder for a plurality of dry cells comprises a tray having a pair of open-top compartments, each receiving a plurality of batteries arranged in series and biased into engagement with one another by a contact spring. A retainer projects over each compartment from a common side wall of the compartments and prevents certain batteries from being removed from their normal positions through the open tops of the compartments, while permitting such removal of other batteries. Sufficient lateral clearance is provided to permit the batteries to move somewhat in response to mechanical shock forces without breaking a desired electrical contact.

Abstract: A magnetic locator in which flux-gate sensors are mounted in longitudinal notches at the ends of a tubular support to form an assembly which is inserted into a tubular housing, the sensors being press-fitted into the notches and the tubular support being provided with spaced bushings of material which is compressed when inserted into the housing. A stiff hairpin excitation conductor extends through the sensors and through the tubular support, being preassembled with one of the sensors and being connected to a circuit chassis for positioning the sensor assembly in the housing. A simplified electrical circuit is employed which produces a beat frequency signal when a magnetic object is located and which avoids the need for a voltage to frequency converter.

Abstract: A magnetic locator in which flux-gate sensors are mounted in longitudinal notches or grooves at the ends of a tubular support to form an assembly which is inserted into a tubular housing, the sensors being press-fitted into the notches and the tubular support being provided with spaced bushings of material which are compressed when inserted into the housing. A stiff hairpin excitation conductor extends through the sensors and through the tubular support, being preassembled with one of the sensors. A simplified electrical circuit is employed which produces a beat frequency signal when a magnetic object is located and which avoids the need for a voltage to frequency converter.

Abstract: An improved flux gate sensor for a magnetic locator or the like employs a housing which enables pivotal adjustment of a tubular magnetic core contained therein in order to adjust the angular orientation of the magnetic axis of the sensor. The housing comprises an elongated bobbin having a longitudinal cavity therein for receiving the core, and an end piece connected to the bobbin. One end of the core is pivotally engaged by the bobbin, the other end of the core being engaged by the end piece which is movable transversely relative to the bobbin to adjust the angular orientation of the core in the housing. The bobbin, which may be formed in one piece or in two identical half sections, has an outer circumferential groove thereon for receiving a signal winding.