摘要:
An ultra-high-frequency notch filter (100) comprises a capacitor (102) defining a conductive trace (106) on its body (103) and extending between its terminals (104). The trace has an inductance that forms a parallel LC circuit with the capacitance of the capacitor. When mounted on a printed circuit board (120) to connect two segments of a signal line (124), the notch filter and a ground plane (122) of the PCB form a virtual conductive loop having an inductance and a capacitance whose product is the center frequency of the notch of the notch filter. The center frequency is tuned by varying the width of the trace.
摘要:
Using a new compound to produce a magnetic tape having low electrical resistivity and high magnetic absorptivity. The magnetic tape self-adheres around a cabinet door opening such that when a cabinet door is closed, the magnetic tape provides an EMI seal with low electrical resistivity and high magnetic absorptivity. In addition, the magnetic tape electrically connects the door to the cabinet. To achieve greater EMI shielding, separate magnetic tape pieces can be positioned on both the cabinet and cabinet door. The compound is of a magnetically lossy Manganese-Zinc (soft ferrite material) having a complex permeability plus cobalt, nickel, or iron (ferromagnetic materials). The Manganese-Zinc material may be Product 3S1, 3S4, 3C11, 3E25 or 3E27 manufactured by the Phillips Corporation of The Netherlands which is readily commercially available.
摘要:
An effective high frequency shielded telecommunication connector system is provided. In particular, a connector shield for covering an access aperture in a shielded enclosure is provided. The connector shield is formed from an electrically conductive material, and provides one or more cable apertures to permit one or more cables to exit the interior of a shielded enclosure. The maximum linear dimensions of any one cable aperture is limited, to eliminate or attenuate the leakage of electromagnetic radiation from an interior of the shielded enclosure. Mounting elements are provided to interconnect the connector shield to the template of the shielded cabinet, and to prevent gaps between the access aperture and its connector shield.
摘要:
An electromagnetic gasket (110) combines a compressible substrate (300, 504/504′, 804) carrying a conductive material (302, 502, 802) and a hook-and-loop fastener (114/304, 400/504/504′, 804) to provide both the mechanical function of removably mounting a door (102) on a cabinet (100) and the electromagnetic function of shielding against EMI emissions even if the door becomes warped.
摘要:
Using an adjustable sleeve that provides electromagnetic interference (EMI) shielding, is lightweight, and is adjustable in its length. The electromagnetic compatibility sleeve is formed by attaching electromagnetic foil shields on one or both sides of an insulating material that is accordion-in-structure in a first embodiment so that its length is flexible. The insulating material can be a very high resistivity and magnetically lossy ferrite material to prevent eddy currents on the inner surface from causing magnetic fields within the insulating material In a second embodiment, the sleeve is made up of telescoping sections so that the length is flexible. This flexible sleeve is attached to systems by the utilization of a mounting bracket, one for each system. The electromagnetic sleeve confines the radiation from a printed circuit extender to within the sleeve and prevents radiation from exiting the systems through enclosure openings by the utilization of the mounting brackets.
摘要:
A universal snap-fit system for interconnecting multiple circuit boards in a stacked relationship is provided. The system allows circuit boards to be stacked with a minimum of assembly time. In addition, the system allows circuit boards of varying thicknesses to be stacked, without requiring the provision of system components in a multitude of sizes. The provided system also allows more than two circuit boards to be interconnected to one another in a stacked relationship without requiring multiple sets of attachment holes in interior circuit boards. In addition, more than two circuit boards can be stacked quickly and easily.
摘要:
The fusible element of an electrical fuse is made from carbon glass. The carbon glass melts and pulls apart safely when the fuse blows, so the fusible element normally does not need an enclosure. The carbon glass glows and emits light when current flowing therethrough approaches the fuse's current-carrying capacity, thereby acting as a current sensor and a warning indicator that the fuse is about to blow.
摘要:
The present locking mechanism for rotatable fastener functions to reliably and inexpensively secure a rotatable fastener in place once it is seated. This is accomplished by the formation of an aperture into the body of the rotatable fastener in a lengthwise direction coaxial with the axis of the cylindrical shaped rotatable fastener. A second aperture is formed in the body of the rotatable fastener perpendicular to the first aperture and intersecting same. A locking pin is placed in the second aperture such that one end of the locking pin is flush with the surface of the body of the rotatable fastener, non-interfering with the operation of the threads formed on the exterior surface of the body of the rotatable fastener. A second end of the locking pin protrudes into the first aperture. A locking post is placed in the first aperture, located above the locking pin and accessible via the open end of the first aperture in the head of the rotatable fastener. A craftsperson uses a tool to force the locking post down into the first aperture to thereby engage the protruding end of the locking pin, forcing the locking pin to move in the second aperture away from the first aperture. The locking pin is thereby driven into the wall of the cylindrical shaped aperture into which the rotatable fastener is threaded and prevents the further rotation of the rotatable fastener in either direction.
摘要:
A passive cascaded low-pass and high-pass filter comprises a conductive ferrite block (100) for filtering out some and not others of the frequencies of a multi-frequency electrical signal, and a pair of electrical contacts (101) on the block for connecting the unfiltered signal to the block and connecting the filtered signal from the block. The filter characteristic depends upon the ferrite's stoichiometry, but is independent of the ferrite's geometry. Signal attenuation caused by the filter evenly across the whole frequency range can be varied by varying the stress between one or both contacts and the block, via various stress-inducing mechanisms (400, 500).
摘要:
An assembly for mitigating at least one of an electrostatic discharge and electromagnetic interference is provided. The assembly includes (a) first and second spaced apart electrical conductors 108 and 116 and (b) a mitigation module 300 electrically coupled to the first and second spaced apart electrical conductors to control a magnitude of an electrostatic discharge and/or electromagnetic interference in the first and second electrical conductors 108 and 116. One or more of the following statements is true: (i) the mitigation module 300 comprises a ferrite material 304; (ii) the mitigation module 300 comprises a lossy dielectric material 308; and (iii) an equivalent electrical circuit for at least part of the mitigation module 300 comprises at least a first circuit segment 512 comprising a first inductor and a first capacitor electrically connected in parallel and a second capacitor 504 electrically connected in series with the first circuit segment 512. The first and second electrical conductors can be, for example, a ground plane of a printed circuit board 108 and a wall of the enclosure or chassis 116.