Abstract: A power line communication system which includes an electrical power line having one or more loads which feed objectionable electrical noise back into the power line. The electrical noise is attenuated across a broad frequency range to enable effective communication over the power line by a directional common mode trap located between the point where the communication signals are applied to the power line and the source of the electrical noise. The trap requires only a capacitor for each electrical phase and a 1:1 transformer having a magnetic core and single turn, straight through windings. The trap is connected to provide a low impedance path to ground for the electrical noise, while providing a high impedance to ground for the communication signals.

Abstract: A bandpass filter comprising a plurality of resonators coupled by a magnetic induction coupling. Each of the resonators includes an equivalent circuit having an LC series circuit and a capacitance element connected in parallel, the LC series circuit including one capacitance element and two inductance elements connected in series to both sides of the one capacitance element. This construction realizes the magnetic induction coupling by utilizing the inductance elements constituting the resonators, without necessitating a separate coupling means such as a capacitance element.

Abstract: An electronic switching arrangement is shown to consist of an effective balanced pi configuration using series and shunt FETs and transformer coupling so that the impedances seen by such FETs are optimized.

Abstract: An adapter for allowing high frequency local area network signals to be transmitted over low cost twisted pair cable. The adapter performs two functions, to act as a converter to match the impedance of the coaxial cable to that of twisted pair cable, as well as an output balancer, to insure that the alternating current or high frequency components of the signals sent over the twisted pair cable are complementary. Only one of the complementary signals carries DC collision information.

Abstract: Four-terminal type noise filter having a first strip-like conductor with first inner and outer input/output leads each connected to the first conductor adjacent each end, a second strip-like conductor with second inner and outer input/output leads each connected to the second conductor adjacent each end, and dielectric sheets superimposed on the respective strip-like conductors. The sandwich of conductors and dielectric sheets are rolled into a flat tube such that the first and second inner leads defines a set of input and output terminals and said first and second outer leads defines another set of input and output terminals. The filter positively minimizes noise received by the filter without creation of ringing.

Abstract: An ac line filter comprises two main cores, at least one auxiliary core disposed between the two main cores, and a pair of windings provided on the main and the auxiliary core. The main cores form shell type closed magnetic paths and enclose the auxiliary core, which forms a closed magnetic path, when the two main cores are placed one over the other. Each of the windings is wound in a concentrated manner to surround both the inner core of the main core and the auxiliary core at a location where the auxiliary core is positioned beside the main core, and is wound in a spaced manner around the inner core of the main core at a location where the auxiliary core is not positioned adjacent the main core. Each winding is divided at the center thereof and the divided ends of one winding are cross-connected with the similar divided ends of the other winding.

Abstract: The protection device in accordance with the invention is connected in series with the line. It comprises either a circuit (1) for providing protection against voltage surges, or else a filter (2) for providing protection against radio frequencies, or else both said circuit and said filter. It protects terminal equipment (telephone set, data terminal, fascimile machine, etc.) against disturbances both in differential mode and in common mode. The device is mounted in a protection connector which may either be of the wall socket type or else of the removable adapter type for plugging into a conventional wall socket, and in either case the terminal equipment has a plug which plugs into a corresponding socket of the protection connector.

Abstract: A noise suppression inductor including a bobbin having a spool divided into a plurality of spool portions, a core mounted on the bobbin, at least one coil wound around the spool portions into a plurality of coil portions and a plurality of terminal pins connected to opposite ends of the coil, in which at least one of the coil portions is composed of a first part having one or two winding layers and a second part having one winding layer and at least another one of the coil portions has not less than two winding layers.

Abstract: A power filter resonant frequency modulation network for coupling between a load and a variable voltage direct current power source which is subjected to superposition of alternating current thereon at various frequencies and at various voltage levels, the filter including first and second series inductor arrangements in the positive and negative buses between the power supply and the load, with capacitive elements in parallel between the two buses. Each series inductor arrangement includes a first inductor in series with a frequency and voltage responsive inductive load device, which is a second inductor having a tertiary winding loaded with a coil wound about the core of a saturable reactor. The firing angles of the reactors are directly proportional to voltage and inversely proportional to voltage to provide a phase staggered change of inductance in the network.

Abstract: A broadband RFI power line filter in which emission filters designed for the 10 KHz to 30 MHz range are combined with high frequency filter elements so as to produce a filter in the 10 KHz to 1000 MHz range. The filter is divided into sections which are constructed in separate electrically isolated compartments so as to increase the attenuation which can be obtained with filters which are not separated from each other and electrically shielded compartments and the level of attenuation which must be achieved from each compartment is reduced in the invention.

Abstract: A power line filter having at least an inductive element and a capacitive element and a circuit network with a coil therein coupled to the inductive element. The circuit network includes a capacitive element and resistive element parallel connected and in parallel with a serially connected inductive element and coil. The coil is closely coupled with the inductive element of the power line filter.

Abstract: A high frequency coil arrangement, comprising an input side coil and an output side coil electromagnetically coupled with each other, the input side coil being divided into two coil elements having substantially equal inductances by provision of a tap, characterized in that two parallel tuner capacitors are provided for the two coil elements for providing two tuner circuits of equal frequencies, and that a further separate capacitor is provided and connected with both ends of the input side coil for adjustment of its tuning frequency.

Abstract: A resonator comprising an equivalent circuit including an LC series circuit having a first capacitance element and inductance elements connected in series to both sides of the first capacitance element, and a second capacitance element connected parallel to the LC series circuit. A plurality of resonators having this construction may be magnetically connected in series to provide a filter, by utilizing the two inductance elements constituting parts of the resonator and without necessitating separate coupling members such as capacitors or coils.

Abstract: A permanent magnet rotor type electrical alternator-SCR power supply having a unique series resonant LC circuit connected to the alternator and resonant close to the lowest expected frequency of the alternator.

Abstract: A loss-impaired filter apparatus for suppressing radio frequency interference on a two-wire line. The apparatus includes a coil unit (10) comprising two coils (e.g. 3a) in the form of printed circuits on either side of an insulating plate (2), a ferrite casing (10a, 10b) surrounding the coil unit (1), there also being two capacitors (15a, 17a, 15b, 17b), the coatings of which are arranged at least practically parallel to the insulating plate (2) on two surfaces of the ferrite elements facing away from each other and facing away from the coil unit (1). Each of the coil conductors is situated directly opposite the other coil conductor along its entire length. The coating (15a, 15b) situated nearest the coil unit (1) in each capacitor is provided with an earth terminal (e.g. 16a) and the other coating (17a, 17b) in each capacitor is connected to the inner end point of the coil (e.g. 3a) situated nearest to the coating.

Abstract: An AC branch power distribution filter is provided for supplying AC power to a plurality of different load devices from a common external AC power source that eliminates the need for a separate protection device at each power outlet with the load devices. A plurality of elongate, flat conductors are coupled to the AC power source and include a neutral conductor, a ground conductor and at least one live conductor. The elongate flat conductors are parallel and spaced apart in an electrically insulated casing member. An electrically conductive shield member is electrically connected to the ground conductor and extends lengthwise of the elongate flat conductors overlying the insulative casing member. The shield member provides a shunt capacitance between ground potential and each of the live conductors and the neutral conductor. This distributed capacitance is utilized as the shunt element of the distribution filter.

Abstract: A notch filter which utilizes a quadrature coupler with the input signal on one of its four terminals, a first tuned surface acoustic wave device coupled to a second on of the terminals for receiving the input signal at 0.degree. phase shift, a second tuned surface acoustic wave device coupled to a third one of the terminals for receiving the input signal with a 90.degree. phase shift and the fourth terminal being utilized as the output signal terminal.

Abstract: A noise filter for an electric wire of star-connected three-phase four-wire system, in which a neutral conductor has a sectional area which is larger than a sectional area of each of voltage conductors. Three voltage conductors are wound on a magnetic core that constitutes a closed magnetic path. The neutral conductor is coupled to the three voltage conductors via three respective capacitors.

Abstract: In a line filter having a first balun, first Y capacitors, a first X capacitor, a second balun, second Y capacitors and a second X capacitor connected between the input and output terminals of the line filter in the order named, the inductance of the first balun is larger than that of the second balun. The total capacitance of the first Y capacitors is larger than that of the second Y capacitors. The line filter can be divided into a front stage containing the first balun and a rear stage containing the second balun, the two stages being coupled via a wiring. The second balun can be constituted by a plurality of baluns.

Abstract: A noise filter for suppressing radiation noises leaking from a signal transmission cable and comprising combination of flat cable segments with a magnetic material core, the magnetic material core being provided with a pair of slits extending in parallel to each other, the flat cable segments each being bent in a U-like shape and inserted at both ends into the slits, so that a noise filter is formed of the magnetic material core fixed to the flat cable segments and both ends of each flat cable segment projecting from one side surface of the magnetic material core are connected to a printed substrate or the like, whereby the flat cable segments as a whole serve as a common mode coil to suppress leakage of noise.

Abstract: Selected interference frequency signals are inserted into the video or RF signal at the transmitter for scrambling purposes, either singly or in pairs. At the receiving end the signals are decoded by use of filters matched to the transmitted signal. The system allows different scrambling for each pay program thereby increasing the security relative to the prior art single frequency system.

Abstract: The present invention provides a track circuit for AC electrified railways, formed by the two rails (R.sub.1,R.sub.2) of a railway section and comprising a transmitter (E) connected to one end of the track circuit for generating therein an alternating signal of given frequency and a receiver (R) connected to the other end for controlling the operation of a track relay (RV). A number of capacitive impedances (Z.sub.1,Z.sub.2, . . . Z.sub.n) with parallel inductance and capacitor (each having a middle point (3) connected to the ground) are connected between the rails (R.sub.1,R.sub.2) while being spaced apart over the whole length of the track circuit with a given pitch (P), depending on the values of the impedances, so that the transmission attenuation of the circuit at the operating frequency is always less than the transmission attenuation of a circuit having the same length formed by a rail with ground return.

Abstract: An apparatus for screening appliances from high frequency interference from the mains supply electrically connected to the appliance has an interference filter being incorporated in the mains plug and comprising at least an induction coil and a capacitor. The capacitors normally used to screen from asymmetric oscillations between the neutral conductor and phase conductor on the one hand and the protective conductor on the other are replaced by a screen of sheeting for the conductor leading from the plug to the appliance. The screen of sheeting is joined to the protective conductor.

Abstract: A bandpass filter is presented which is constructed so that bandwidth of the bandpass filter may be varied without varying gain from an input signal to an output signal when the input signal is at a center frequency. A crystal resonator is connected in series with a compensation resistance, and a variable resistance. Ignoring shunt capacitance, the crystal resonator may be modelled by a capacitance, an inductance and a loss resistance coupled in series. The compensation resistance is chosen so that the voltage drop across the compensation resistance is equal to the voltage drop across the loss resistance. A transformer having a primary coil, a secondary coil, and a 1:1 turn ratio between the two coils is included in the circuit. The primary coil is coupled in parallel with the compensation resistance. The output signal appears at an output of the secondary coil.

Abstract: An impedance element formed from a single-port, surface acoustic wave transucer which generates a conductance versus frequency response characteristic having first and second peaks separated by a valley at a predetermined frequency and which generates a susceptance versus frequency response characteristic having a substantially constant portion over a finite bandwidth on both sides of said predetermined frequency.

Abstract: An electronic component made by the steps of: preparing elongated tape (10), distributing a plurality of pairs of electronic elements (1) over the tape (10) lengthwise of the latter and bonding the pairs to the tape (10) in such a manner that the two elements (1) in each pair are positioned one in each of the first and second regions (12, 13) of the tape (10) separated from each other substantially by the longitudinal centerline (11) of the tape (10), folding the tape (10) along the longitudinal centerline (11) so that the two elements (1) in each pair are opposed at least partially to each other, preparing a terminal assembly (18) having a frame (17) on which a plurality of terminals (14, 15, 16) to be connected to the elements (1) are held so that they are distributed lengthwise of the frame (17), arranging the frame (17) parallel to the tape (10) and effecting connection between the terminals (14, 15, 16) and the elements (1), cutting the tape (10) along widthwise extending cutting lines to separate the se

Abstract: An improved notch filter having a single port, surface acoustic wave transducer in parallel with an inductor and forming a first circuit which primarily blocks the signal frequency at all frequencies except the notch frequency at which point the first circuit becomes essentially resistive and at that point is cancelled by a signal from a second circuit in parallel with said first circuit and which is 180.degree. out-of-phase thereby providing a notch filter.

Abstract: An impedance bond for use in an electrified railway to provide a path for traction current includes a housing and a core positioned within the housing. The core is formed of a band of silicon steel wound into a closed loop construction which is then severed to form a cap and a U-shaped body. A pair of coils are positioned each upon a leg of the U-shaped core prior to repositioning the cap upon the core. Each of the coils is substantially identical in electrical resistance and each is formed of a flat copper sheet, identical in length, and wound into coils identical in configuration. There are terminal straps attached to the coil which extend outwardly from the housing. The terminal straps are preferably cast copper.

Abstract: An intermediate frequency band-pass filter for providing a pass band, comprising a frame forming a hollow surrounded region, a shield plate mounted in the frame and dividing the hollow surrounded region into two spaces, the shield plate having a coupling window, and two resonators disposed respectively in the spaces and coupled through the coupling window, the shield plate having in an edge thereof a step serving as a trap which provides a frequency suppression capability in the vicinity of the pass band of the filter.

Abstract: A network for matching an electrical source of audio signals to a piezoceramic driver for a high frequency loudspeaker. The network consists of all of the elements of a bandpass filter network, but with the parallel combination of an inductor and a capacitor in the output stage of the filter replaced by an autotransformer or autoinductor which transforms the input impedance of the piezoceramic transducer into an equivalent parallel capacitance and resistance which, together with the inductance of the autotransformer, supply the load resistance for the filter and replace the capacitor and inductor omitted from the output stage of the bandpass network. An additional shunt resistor may be placed across the output of the autotransformer to obtain the desired effective load resistance at the input of the autotransformer.

Abstract: A two resonator bandpass filter that is tunable is disclosed with each resonator consisting of three series connected inductors and a tuning capacitors. The inductors comprising each resonator are contained in a common enclosure isolated from each other by a ground shield having a fixed aperture opening for electromagnetic coupling between the two resonators. Shorting plugs are used as the bandswitching techniques for switching the bands of the resonators. Variable capacitors in each of the resonator's circuit provide for tuning of each band to a desired frequency.

Abstract: A band-pass filter circuit has series elements, comprising a parallel resonant circuit and a first inductance, and shunt elements comprising a series resonant circuit and a second inductance, the resonant circuits comprising variable capacitances to permit variation of the frequency over a frequency band. The second inductance may be a transformer. The variable capacitances may be constituted by a plurality of switchable component capacitances, having switches connected between the capacitances and ground.

Abstract: A four-terminal network, especially for filtering frequency bands or values, behaves as an ideal winding, therefore ensures high selectivity and, if equipped with an iron core, the possibility of carrying out switch operations. The network includes a pair of closely adjacent inductor coils having parallel turns for current in opposite directions, and equal inductance with a capacitor connected to at least one end of one of the coils.

Abstract: A capacitor structure comprises a single sheet of spirally-wound conductive material having an insulative layer disposed on one side. In contrast to previously-employed capacitor structures, the structure of the present invention includes only a single conductive sheet of material not a plurality of conductive plates or layers. In particular, the present invention is readily employable in magnetic circuits, particularly those employing magnetic core material. In these circuits, the capacitor is installed without the requirement of external leads and is readily integrated with the core structure. The instant capacitor structure is also particularly useful in constructing multi-stage LC filter circuits.

Abstract: An AC power supply system having transformer and filter structures. The electrical center of the filter section, which is normally connected to system ground, floats with respect to system ground and is connected to a center tap on the secondary winding of the transformer structure.

Abstract: A multi-legged transformer core is employed to integrate into a single structure the discrete magnetic components required to form a multiple stage inductor-capacitor filter. The device may be employed in low pass filters used with inverters to remove high order harmonic frequency signals. The filter of the present invention is particularly useful in discharge lamp ballast circuits.

Abstract: Filter circuits of the type having inductance and capacitance elements, wherein the number of magnetic components is reduced by using two transformers to perform the functions of four individual inductors. Each transformer has one end of the primary winding connected to one end of the secondary winding, and a pi or T equivalent circuit in which one of the inductance values is equal in magnitude and opposite in sign to a corresponding equivalent circuit inductance value of the other transformer.

Abstract: A noise filter with a socket attached thereto including a case made of metallic material mounting a pair of pierce type (feed through) capacitors and a power input socket having a pair of power input contacts and a grounding contact, a choke coil having a pair of coil windings wound thereabout and a capacitor interposed between said pair of coil windings mounted inside said case, said pierce type capacitors including inner piercing (feed through) terminals and outer terminals, said power input contacts and the piercing terminals of said pierce type capacitors being connected to one another via said coil windings, and said grounding contact and the outer terminals of said pierce type capacitors being electrically connected to the case.

Abstract: In an electrodeless discharge lamp of the type including an ionizable medium within a sealed envelope capable of emitting radiant energy when subjected to a radio frequency field, an oscillator for generating an output signal at a given radio frequency of 13.56 MHz, an RF amplifier responsive to the oscillator output signal, and an induction coil and a capacitor connected in series and responsive to the output of the amplifier, the coil being positioned in close physical proximity to the medium in the envelope for coupling to the medium an electric field having a magnitude sufficient to initiate ionization of the medium and a magnetic field for maintaining ionization, there is disclosed an improvement wherein a Class D amplifier drives the series connected coil and capacitor without a separate load circuit connected in the output circuit of the amplifier. A specially selected filter and matching network coupled between the Class D amplifier and the series connected coil and capacitor reduces CV.sup.

Abstract: A line choke is disclosed for use in attenuating interfering emissions on a power line. The choke includes a ferrite core having four holes extending through it. A pair of windings are threaded through the holes and around the center of the core so that the windings crisscross to enhance the mutual coupling between them. Interfering emissions received by the choke are greatly attenuated at relatively low frequencies by the choke acting as a pi section filter, and higher frequency emissions are attenuated by the choke action as a very lossy transmission line.

Abstract: Band-stop filter for equipment with carrier-frequency utilization of low-voltage lines, including a current-compensated choke having a closed ferrite core, two center taps, and two coil halves each of which having windings being connected to one of the center taps and wound with the same sense on the closed ferrite core, and a capacitor connected between the center taps.

Abstract: Input signals having a particular impedance in a particular frequency range are provided. A first transformer has at its input a particular impedance in the particular frequency range and provides a change at its output to a second impedance in the particular frequency range. A filter is constructed to receive the signals from the first transformer and is provided with the second impedance in the particular frequency range. When the second impedance is lower than the particular impedance, the operation of the filter at the second impedance is advantageous because the size of the inductances in the filter is significantly reduced without impairing the quality of the inductances or increasing energy losses in the inductances.A second transformer is constructed to receive the signals from the filter. The second transformer provides the second impedance at its input and provides at its output a change to the particular impedance in the particular frequency range.

Abstract: An electrical power line transient noise filtering device is disclosed in the specification and drawings comprising a step up transformer connected to two continuous resistors. The high voltage winding of a step down transformer is connected to the other ends of the resistors. Low frequency power passes easily through the system but noise pulses are effectively blocked because they must pass through a transmission line of high loss.

Abstract: An EMC-/EMI-filter module for use with unscreened data and signal lines comprises a LC filter utilizing a quadruple inductance is contained in a 16 terminal dual-in-line package with a specified raster dimension.

Abstract: The present invention uses two interconnected baluns with the balanced output of one feeding a balanced input of the other. When this filter is used in conjunction with a signal frequency converter, the balun pair not only provides extremely effective bandpass filtering so as to pass the RF frequencies and not the IF frequencies but, in addition, provides a condition which appears to the IF as a nearly open circuit and thus provides a large amount of reflection or return of the IF signals to the signal converter. Through the use of additional grounding stubs, additional coupling means, increased separation between coupling means and separated ground planes each singularly or in combination, improved performance has been obtained as compared to the prior art.

Abstract: An RF coaxial connector assembly, having an inner and outer conductor, employs a washer-like capacitor fitted over the outer conductor for low frequency isolation and employs a transformer adapted for connection between a source of RF signals and the inner and outer conductors of the assembly for reducing the RF currents on the outer conductor. Reduction of the RF currents on the outer conductor is effective to reduce the radiation of RF energy from a coaxial cable coupling the connector assembly to the load.

Abstract: A balanced, doubly tuned gate couples between the mixer and intermediate frequency (IF) stages of a conventional radio receiver. The network is comprised of a pair of matched transformers interconnected in a balanced configuration, with the first transformer tuned to the mixer and the remaining transformer tuned to the IF stage. Capacitors interconnect the two transformers resulting in a Butterworth filter network.Two diode pairs connect in shunt across selected windings of the transformers. Direct current bias normally biases the diodes to a nonconducting state, thereby allowing the mixer signals to pass to the IF stage. A blanking signal from the receiver blanker drives the diodes to conduction thereby decoupling the mixer from the IF and blanking the receiver.Due to the doubly balanced nature of the gate, blanking is accomplished with a minimum of switching time. Moreover, the shunt diode switching scheme provides superior attenuation in the blanking mode and enhanced operation in the normal mode.

Abstract: A passive circuit element for influencing pulses has two series-connected inductances which connect a first input terminal to a first output terminal, a first capacitor which is connected between the connection point of the inductances and the second terminals which are either directly connected to one another or which coincide with one another. The inductances are formed by spiral conductor paths which are arranged on a substrate and which are oppositely directed to one another. The spiral conductor paths are arranged concentrically above one another in two different conductor path layers which are separated by an insulating layer. The inner ends of the spiral conductor paths are connected by means of a contact extending through the insulating layer and to which a plate of the first capacitor is also connected.