In embodiments of the invention, the present invention is directed to a contact hearing system including: a transmit coil positioned in an ear tip wherein the transmit coil includes an electrical coil wound on a ferrite core; a receive coil positioned on a contact hearing device wherein the receive coil includes an electrical coil without a core; a load connected to the receive coil; and a demodulation circuit connected to the receive coil and the load wherein the demodulation circuit includes a voltage doubler and a peak detector.

In embodiments of the invention, the present invention is directed to a contact hearing system including: a transmit coil positioned in an ear tip wherein the transmit coil includes an electrical coil wound on a ferrite core; a receive coil positioned on a contact hearing device wherein the receive coil includes an electrical coil without a core; a load connected to the receive coil; and a demodulation circuit connected to the receive coil and the load wherein the demodulation circuit includes a voltage doubler and a peak detector.

A downhole tool may include a high-voltage power supply disposed within a housing to transform input power to the downhole tool from a first voltage to a second voltage greater than the first voltage. The high-voltage power supply may include an array of capacitors, which may include multiple rows of capacitors. The rows of capacitors may be parallel with a symmetric cross section as viewed from an end of the array of capacitors. The high-voltage power supply may also include diodes electrically coupled to the array of capacitors.

An AC to DC conversion device has first and second AC input terminals arranged to be coupled respectively to first and second terminals of a phase of an AC current generator, an H-bridge rectification device comprising two pairs of diodes, each pair being coupled to a respective one of the AC terminals to produce a DC output comprising a rectified back EMF waveform, and a waveform generator. The waveform generator comprises an output coupled to the DC output of the H-bridge rectification device, and is configured to input a unidirectional waveform to the DC output having the same magnitude and fundamental frequency as the rectified back EMF, phase shifted by a predetermined angle relative to the rectified back EMF waveform.

In one embodiment, the present invention is directed to a method of transmitting information from an ear tip to a contact hearing device, the method comprising the steps of: exciting a transmit coil, the transmit coil being positioned in the ear tip, wherein the transmit coil is wound on a core, the core including a ferromagnetic material; radiating an electromagnetic field from the first coil through the ear canal of a user; receiving the radiated electromagnetic field at a receive coil, the receive coil being positioned on a contact hearing device, the contact hearing device including a receive coil without a ferrite core; and transmitting the information from the transmit coil to the receive coil using, for example, near-field radiation.

In one embodiment, the present invention is directed to a method of transmitting information from an ear tip to a contact hearing device, the method comprising the steps of: exciting a transmit coil, the transmit coil being positioned in the ear tip, wherein the transmit coil is wound on a core, the core including a ferromagnetic material; radiating an electromagnetic field from the first coil through the ear canal of a user; receiving the radiated electromagnetic field at a receive coil, the receive coil being positioned on a contact hearing device, the contact hearing device including a receive coil without a ferrite core; and transmitting the information from the transmit coil to the receive coil using, for example, near-field radiation.

A multiway switching device may comprise a wireless device in communication with a relay and a manual switch of the device. A toggle state of the relay may be indicative of an electrical configuration between conductors and rectifier circuits of the multiway switching device. The wireless device may receive, from the manual switch or from an external device, a signal indicative of a modification to the toggle state of the relay. Based on the signal, the wireless device may cause the modification to the toggle state of the relay. The wireless device may cause output of a status signal indicative of the modification to the toggle state of the relay.

A multiway switching device may comprise a wireless device in communication with a relay and a manual switch of the device. A toggle state of the relay may be indicative of an electrical configuration between conductors and rectifier circuits of the multiway switching device. The wireless device may receive, from the manual switch or from an external device, a signal indicative of a modification to the toggle state of the relay. Based on the signal, the wireless device may cause the modification to the toggle state of the relay. The wireless device may cause output of a status signal indicative of the modification to the toggle state of the relay.

A power supply circuit is provided with: an AC voltage supply part; and one or more Cockcroft-Walton circuits. The one or more Cockcroft-Walton circuits include a plurality of output terminals and are supplied with an AC voltage from the AC voltage supply part. The plurality of output terminals are configured to output different DC potentials for each output terminal according to a magnitude of the AC voltage.

A power conversion device and a press apparatus capable of preventing an excessive current in a DC-link capacitor are provided. The power conversion device 10 includes a voltage-doubling rectifier circuit 12. In the voltage-doubling rectifier circuit 12, in a voltage-doubling rectification mode, a common connection node Nc between two capacitors 102a and 102b is connected to a predetermined node. A current detector circuit 107 detects a switching current (IL) flowing in the switching elements SW1 and SW2, and a current detector circuit 108 detects a load current Ild of a load 15. In a mode switching period from a full-wave rectification mode to a voltage-doubling rectification mode, a controller circuit 110 controls the switching of the switching elements SW1 and SW2, based on the switching current (IL) and the load current Ild.