A magnetically tunable ferrimagnetic filter, including a top casing, a top magnetic conductor, a bottom magnetic conductor, coils, a balance coil, ferrimagnetic-based filters, and a bottom casing. The ferrimagnetic-based filters utilize ferrimagnetic resonator elements, such as yttrium-iron-garnet (YIG), configured to reduce a magnetic gap of the YIG filter and thereby to improve performance.

A substrate module according to an embodiment of the present invention comprises: a first substrate which includes transformer connection part to be connected to terminals of a transformer, at least one second substrate on which a switch module to be connected to the transformer is formed; and a conductive connector which connects the first substrate and the second substrate to each other, wherein the first substrate and the second substrate are arranged by the conductive connector such that a predetermined angle is formed therebetween.

Disclosed herein is a coil component that includes an element body having first and second magnetic layers and a coil part positioned therebetween, and first and second external terminals formed on the element body. The first external terminal is formed on the mounting surface and the first side surface. The second external terminal is formed on the mounting surface and the second side surface. The first and second external terminals formed on the first and second side surfaces, respectively, have a meander shape.

A battery pack charging system includes a battery pack interface configured to receive a battery pack, a charging circuit coupled to the battery pack interface to provide charging current to the battery pack interface, and a controller coupled to the charging circuit and configured to control supply of charge current to the battery interface. The battery pack charging system further includes a power supply circuit coupled to the charging circuit, a filter circuit coupled to the power supply circuit and including a nanocrystalline ferrite common mode choke, and an alternating current plug configured to connect the filter circuit to an alternating current power source.

A current transformer includes a first housing including a first handle portion and a first distal portion, a second housing including a second handle portion and a second distal portion, a first core having a first proximal core end and a first distal core end the first core mounted in rotational contact within the first distal portion, and a second core having a second proximal core end and a second distal core end, the second core mounted in rotational contact within the second distal portion, wherein the first housing is rotationally coupled to the second housing about a fulcrum point.

A coil component includes a core including a winding core portion, a first flange portion, and a second flange portion, and a first wire and a second wire that are wound around the winding core portion in the same direction and that form a winding portion. The winding portion includes a second intersecting portion along a third side surface of the winding core portion at a position on the winding portion nearest to the second flange portion.

A combined transformer/inductor device includes a core having a central core leg and an outer core leg spaced apart from the central core leg, an inner bobbin disposed around the central core leg, an outer bobbin disposed around the inner bobbin and the central core leg and having an upper portion having a first oblong portion disposed around the outer core leg, a lower portion having a second oblong portion disposed around the outer core leg, and a central portion disposed around the inner bobbin and the central core leg, a first winding wound around the inner bobbin, and a second winding wound around the outer bobbin, the second winding having a first portion wound around the first oblong portion, a second portion wound around the central portion, and a third portion wound around the second oblong portion.

A frac dart including an electric counter in the frac dart, an inductor in the frac dart, in electrical communication with the counter, the inductor generating a voltage responsive to the dart moving through a magnetic field. A method for selectively landing a dart on a landing feature in a well including sensing a landing feature by generating an inductor signal with an inductor pursuant to the inductor passing through a magnetic field associated with the landing feature in the well. generating a count in an electrical counter of the dart responsive to the inductor signal, applying a count signal to a switch of the dart based upon the count, selectively passing the count signal to an activator or an actuator of the dart based upon switch position.

A current transformer includes a first housing including a first handle portion and a first distal portion, a second housing including a second handle portion and a second distal portion, a first core mounted in the first distal portion, a second core mounted in the second distal portion, and a lock attached to the second handle portion at a pivot point, wherein the first housing is rotationally coupled to the second housing about a fulcrum point and the lock is rotatable about the pivot point into a closed position wherein the lock engages the first handle portion and prevents the first handle portion and the second handle portion from rotating towards each other.

A current transformer includes a housing including generally cylindrical outer and inner walls defining an internal chamber, a front face enclosing one end of the internal chamber, a base, and a central opening defined by the inner wall. A generally toroidal current transformer core is disposed within the internal chamber. A secondary wiring is disposed about the transformer core and is configured to generate a current in response to magnetic flux in the transformer core. A pin housing is disposed on the front face of the housing adjacent the base. The pin housing has electrically conductive pins. A test wire passes through the central opening. The secondary wiring is electrically connected to a first pair of the pins and the test wire is electrically connected to a second pair of the pins.