Provided are a disturbing magnetic field generator and a card reader capable of suppressing the generation of noise caused by vibration of a core. A disturbing magnetic field generator that generates a disturbing magnetic field for disturbing unauthorized reading of magnetic data recorded on a card includes a coil to generate the disturbing magnetic field, a bobbin including a tubular body part in which the coil is wound on an outer peripheral side, and a core disposed inside the tubular body part. A first gap is provided between the tubular body part and the core.

A technique for tamper protection of incoming data signal to an electronic device is disclosed. An intentional interference signal is generated and modulated onto the incoming data signal as one composite input signal, to prevent unauthorized acquisition of valid data from the incoming data signal. The magnitude of the interference signal is adjusted to correspond to the magnitude of the incoming data signal, thereby preventing an attacker from properly differentiating the two different signals and/or decoding the valid data from the composite input signal. Once the composite input signal is safely received within the device, the interference signal can be filtered out in either analog mode or digital mode.

A card reader may include a card insertion port; a card passage; and a disturbing magnetic field generator. The disturbing magnetic field generator may include a first disturbing magnetic field generation part and a second disturbing magnetic field generation part which are disposed so as to interpose the card passage. The first disturbing magnetic field generation part may include a first core formed of magnetic material and a coil wound around the first core, and the second disturbing magnetic field generation part may include a second core formed of magnetic material and a coil wound around the second core.

A method for manufacturing a magnetic core module in a magnetic head, the magnetic core module and the magnetic head. The method for manufacturing the magnetic core module includes: a process for placing a magnetic core group in a holder mold cavity as an insert; and a process for injection-molding in the holder mold cavity. A method for manufacturing the magnetic core module allows the magnetic core group and the holder to be integrally injection-molded with a method of injection molding which uses the magnetic core group as an insert. The method simplifies the process of manufacturing a magnetic head to improve production efficiency, and saves labor and production costs. Further, the method prevents failures such as positional displacement and scattering of magnetic cores, which tends to occur when assembling thin and small magnetic cores, and ensures an ideal yield for a product.

Provided are a disturbing magnetic field generator and a card reader capable of suppressing the generation of noise caused by vibration of a core. A disturbing magnetic field generator that generates a disturbing magnetic field for disturbing unauthorized reading of magnetic data recorded on a card includes a coil to generate the disturbing magnetic field, a bobbin including a tubular body part in which the coil is wound on an outer peripheral side, and a core disposed inside the tubular body part. A first gap is provided between the tubular body part and the core.

A card reader includes a writing coil that is provided to a magnetic head for recording magnetic data in a magnetic card, and a drive circuit that supplies a write current to the writing coil. The drive circuit is a chopping circuit that supplies a chopping current, on/off of which is switched in a specified cycle, as the write current to the writing coil. An on/off cycle of the chopping current is a cycle in which a length of a magnetized pattern in a recording direction is shorter than a reading gap formed in a core around which the writing coil is wound or a core around which a reading coil being separately provided from the writing coil is wound, the magnetized pattern in the recording direction being formed in the magnetic card by the chopping current in a period including one each of the on and the off.

Various embodiments include, for example, a digital-card reader, a reader hub, and a method of determining a coefficient of friction for mounting the digital-card reader and the reader hub to a mounting surface. In one specific embodiment, the digital-card reader includes a card-reader frame having a circuit board including at least one memory-card reader to perform data transfer operations; a magnetic material coupled to at least one face of the card-reader frame; and a compliant-region mat coupled to the at least one face of the card-reader frame and positioned proximate to the magnetic material. The magnetic material compresses the compliant-region mat to increase friction against a mounting surface to at least partially overcome insertion forces associated with inserting the memory card into the digital-card reader to reduce or eliminate lateral movement of the digital-card reader with reference to the mounting surface. Other devices, apparatuses, and methods are described.

A card reader includes a writing coil that is provided to a magnetic head for recording magnetic data in a magnetic card, and a drive circuit that supplies a write current to the writing coil. The drive circuit is a chopping circuit that supplies a chopping current, on/off of which is switched in a specified cycle, as the write current to the writing coil. An on/off cycle of the chopping current is a cycle in which a length of a magnetized pattern in a recording direction is shorter than a reading gap formed in a core around which the writing coil is wound or a core around which a reading coil being separately provided from the writing coil is wound, the magnetized pattern in the recording direction being formed in the magnetic card by the chopping current in a period including one each of the on and the off.

Various embodiments include, for example, a digital-card reader, a reader hub, and a method of determining a coefficient of friction for mounting the digital-card reader and the reader hub to a mounting surface. In one specific embodiment, the digital-card reader includes a card-reader frame having a circuit board including at least one memory-card reader to perform data transfer operations; a magnetic material coupled to at least one face of the card-reader frame; and a compliant-region mat coupled to the at least one face of the card-reader frame and positioned proximate to the magnetic material. The magnetic material compresses the compliant-region mat to increase friction against a mounting surface to at least partially overcome insertion forces associated with inserting the memory card into the digital-card reader to reduce or eliminate lateral movement of the digital-card reader with reference to the mounting surface. Other devices, apparatuses, and methods are described.

Provided is a magnetic recording medium processing device including a loading slot into which a magnetic recording medium, a medium movement path extending from the loading slot, a first magnetic head arranged in the medium movement path and detecting a magnetic signal from the magnetic recording medium, a magnetic information reproducer reproducing the magnetic information, based on a signal of a specific frequency included in analog signals output from the first magnetic head, an interfering magnetic field generator generating an interfering magnetic field along the medium movement path, and an interfering magnetic field controller controlling the interfering magnetic field generator to generate a first interfering magnetic field until the first magnetic head starts detecting the magnetic signal, and controlling the interfering magnetic field generator to generate a second interfering magnetic field different in frequency spectrum from the first interfering magnetic field while the first magnetic head detects the magnetic signal.