Abstract: 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.

Abstract: A method and apparatus used for designing printed circuit boards to meet current leakage requirement by determining an approximate model of electric fields based on a structure between two conductors on an outer surface of a printed circuit board; deriving an effective permittivity of the model of the electric fields; calculating a plurality of electric fields using the derived effective permittivity by varying a distance between the two conductors, a thickness of the printed circuit board, and an applied voltage between the two conductors; plotting a graph of the calculated plurality of electric fields; and selecting by using the graph a configuration of the two conductors so as to meet the current leakage requirement. A printed circuit board has a set of conductors on the outer surfaces of the printed circuit board; another set of conductors interior to the printed circuit board; and a solder mask that covers only the set of conductors on the outer surfaces of the printed circuit board.

Abstract: 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.

Abstract: 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.

Abstract: A high density capacitor filter bank for use in connection with printed circuit boards is provided. Capacitive elements are disposed within a conductive shield such that the capacitive elements are substantially orthogonal to the plane of the printed circuit board, and such that they can interconnect with corresponding contacts on the printed circuit board while occupying a minimal amount of surface area on the printed circuit board. The conductive shield may comprise a Faraday shield.

Abstract: 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.

Abstract: An electromagnetically-shielded enclosure is formed by applying an electromagnetic-shielding film to a plastics enclosure by the water-borne film application process. The film is formed from a mixture comprising a polymer and a conductive material, such as lossy ferrite, carbon glass, or metal, that constitutes 20 to 40 percent by weight of the mixture.

Abstract: 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.

Abstract: 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.

Abstract: A snap mounted electrical power connector for a printed circuit board. The electrical power connector is included of an input power receptacle that forms a first portion of a current carrying path through the electrical power connector and an output power receptacle that forms a second portion of the current carrying path through the electrical power connector. The input power receptacle and the output power receptacle are configured to connect along a common axis perpendicular to the printed circuit board by a snap connection.

Abstract: 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.

Abstract: 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.

Abstract: A coil former for constructing coil transformers. The coil former comprises a rectangular casing having a central interior cavity. The casing is configured to form the coil for the transformer and connect and align a pair of transformer cores to form a substantially homogeneous transformer core. The casing is further configured to connect the coil leads to the homogeneous transformer core to produce a coil transformer.

Abstract: The high-voltage surge performance of a Centronic connector (100) is improved through increasing the free-air distance (120′, 120″) between adjacent pins (102′, 102″) by tapering the portions of pin bodies (301′, 301″) that extend outwardly from the insulating molding (101) of the connector. The bodies may taper either monotonically (FIG. 5) or concavely (FIG. 7). Additional improvement is obtained by extending the tapered pin-body portions into the molding (FIG. 6) and/or by making the molding with ribs (800) that extend outwardly between adjacent pins (FIG. 8) or by thickening the molding.

Abstract: An all-optical-loop buffer (100) that restores the extinction ratio of the buffered signal such as an ATM cell. The buffer takes advantage of the cross-gain compression and wavelength shifting effected by semiconductor optical amplifiers (SOAs 118, 132). A received signal (.lambda..sub.1) is coupled (104) to the buffer loop (101), amplified (110), and combined (114) with a low-energy unmodulated second signal (116) at a different wavelength (.lambda..sub.2). The combined signal is amplified by an SOA (118) to modulate the second signal with an inverse of the modulation of the first signal. The received signal is extracted (128) from the SOA's output and attenuated (126). The modulated second signal is extracted (124) from the SOA's output, amplified (122), and combined (130) with the extracted received signal.

Abstract: The planar magnetic continuous-tone transducer functions as a low power, wide dynamic range speaker. The planar magnetic continuous-tone transducer uses a conventional pair of ferrite cores on which are tightly wound primary and secondary coils. A very small air gap is provided between the two ferrite cores and the secondary coil is left unterminated. The application of a voltage at a selected frequency to the primary coil induces a harmonic force in the open secondary coil, which is transmitted to the two ferrite cores. The harmonic force causes the ferrite cores to vibrate, emitting a tone from the air gap region.

Abstract: An optical wavelength-division multiplexed bidirectional data link (FIG. 1) is constructed using a single multi-mode fiber (130). The link comprises the optical fiber with a single-lens optical transceiver (100, 150) at each end of the fiber. Each single-lens optical transceiver comprises a transmitter in the form of a surface-emitting light-emitting diode (LED 101) that emits light at a wavelength of 0.85 .mu.m, and a receiver in the form of a large-scale optical detector (102) and a dielectric optical filter (103) that has a passband at a wavelength of 1.3 .mu.m. In the other transceiver, the wavelengths of the transmitter and the receiver are reversed. The transceiver is made as a single integrated-circuit device and is coupled to the fiber by a single-lens optical coupler (110, 160).

Abstract: The multi-functional clip provides two functions: holding a plurality of multi-layer magnetic transformers together in a vertical stack; holding together the respective E-Cores of each of the plurality of multi-layer magnetic transformers. This is accomplished by the use the multi-functional clip that comprises a body, having four tapered flanges that extend vertically from the periphery of the body to form the arms that enclose and contact the multi-layer magnetic transformers. The vertically oriented arms each include a feature formed at a distal end thereof that mates with a recess formed in a side of a corresponding one of the multi-layer magnetic transformers. The vertically oriented arms are manufactured of a spring material to thereby apply a horizontal force to the multi-layer magnetic transformer.

Abstract: 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.

Abstract: A printed circuit (PC) board-mountable ferrite electromagnetic interference (EMI) filter (702, 1003, 1003") for PC conductors (701, 1001, 1002) of a printed circuit (PC) board (700, 1000) that accommodates large numbers of PC conductors, and is cost-effective. One embodiment of the EMI filter is used with a PC board (700) that routes PC conductors (701) in a step-function (i.e., a "U"-shaped) pattern. The EMI filter comprises a ferrite body (702) that defines two parallel passageways (708, 709), i.e., has a figure-8 shape in cross section. The portion (710) of the PC board that defines the PC conductor portions extending in the one direction lies in one passageway, whereas the portion (711) of the PC board that defines the PC conductor portions extending in the other direction lies in the other passageway. A different embodiment of the EMI filter is used with a PC board (1000) that routes sets (1001, 1002) of PC conductors in a cross-hatch (i.e.