82 relations: Admittance, Analogue filter, Antenna (radio), Antenna tuner, AT&T Corporation, Attenuation, Audio frequency, Balanced line, Bell Labs, Carl Emil Krarup, Carrier system, Characteristic impedance, Coaxial cable, Constant k filter, Coupling (electronics), Cutoff frequency, Dielectric loss, Digital subscriber line, Dipole antenna, Distortion, Distributed element model, Electrical impedance, Electrical length, Electrical reactance, Electrical resistance and conductance, Electrically small antenna, Electronic circuit, Enderby's Wharf, Feed line, Frequency-division multiplexing, General Post Office, George Ashley Campbell, Heaviside condition, Helsingør, Helsingborg, Horta, Azores, Image impedance, Inductance, Inductor, John Stone Stone, Joseph-Louis Lagrange, Litz wire, Low frequency, Low-pass filter, Lumped element model, M-derived filter, Magnetic flux, Mihajlo Pupin, Monopole antenna, Mu-metal, ..., New York City, Oliver Ellsworth Buckley, Oliver Heaviside, Operational calculus, Optical fiber, Passband, Permalloy, Permeability (electromagnetism), Phantom circuit, Primary line constants, Propagation constant, Proximity effect (electromagnetism), Radiation resistance, Repeater, Resonance, Resonator, Serbia, Skin effect, Standing wave, Standing wave ratio, Submarine communications cable, T-carrier, Transatlantic telegraph cable, Transformer, Transmission line, Twisted pair, Very low frequency, Voice frequency, Waveform, Wavelength, Western Electric, Western Union. Expand index (32 more) » « Shrink index
In electrical engineering, admittance is a measure of how easily a circuit or device will allow a current to flow.
Analogue filters are a basic building block of signal processing much used in electronics.
In radio, an antenna is the interface between radio waves propagating through space and electric currents moving in metal conductors, used with a transmitter or receiver.
An antenna tuner, a matchbox, transmatch, antenna tuning unit (ATU), antenna coupler, or feedline coupler is a device connected between a radio transmitter or receiver and its antenna to improve power transfer between them by matching the impedance of the radio to the antenna's feedline.
AT&T Corp., originally the American Telephone and Telegraph Company, is the subsidiary of AT&T that provides voice, video, data, and Internet telecommunications and professional services to businesses, consumers, and government agencies.
In physics, attenuation or, in some contexts, extinction is the gradual loss of flux intensity through a medium.
An audio frequency (abbreviation: AF) or audible frequency is characterized as a periodic vibration whose frequency is audible to the average human.
In telecommunications and professional audio, a balanced line or balanced signal pair is a transmission line consisting of two conductors of the same type, each of which have equal impedances along their lengths and equal impedances to ground and to other circuits.
Nokia Bell Labs (formerly named AT&T Bell Laboratories, Bell Telephone Laboratories and Bell Labs) is an American research and scientific development company, owned by Finnish company Nokia.
Carl Emil Krarup (12 October 1872 – 29/30 December 1909) was a Danish telegraph engineer who is chiefly known for the invention of a kind of loaded cable, eponymously called Krarup cable, which made improvements in the transmission of telephone signals, especially on submarine cables.
A carrier system is a telecommunications system that transmits information, such as the voice signals of a telephone call and the video signals of television, by modulation of one or multiple carrier signals above the principal voice frequency or data rate.
The characteristic impedance or surge impedance (usually written Z0) of a uniform transmission line is the ratio of the amplitudes of voltage and current of a single wave propagating along the line; that is, a wave travelling in one direction in the absence of reflections in the other direction.
Cross-sectional view of a coaxial cable Coaxial cable, or coax (pronounced), is a type of electrical cable that has an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield.
Constant k filters, also k-type filters, are a type of electronic filter designed using the image method.
In electronics and telecommunication, coupling is the desirable or undesirable transfer of energy from one medium, such as a metallic wire or an optical fiber, to another medium.
In physics and electrical engineering, a cutoff frequency, corner frequency, or break frequency is a boundary in a system's frequency response at which energy flowing through the system begins to be reduced (attenuated or reflected) rather than passing through.
Dielectric loss quantifies a dielectric material's inherent dissipation of electromagnetic energy (e.g. heat).
Digital subscriber line (DSL; originally digital subscriber loop) is a family of technologies that are used to transmit digital data over telephone lines.
In radio and telecommunications a dipole antenna or doublet is the simplest and most widely used class of antenna.
Distortion is the alteration of the original shape (or other characteristic) of something.
In electrical engineering, the distributed element model or transmission line model of electrical circuits assumes that the attributes of the circuit (resistance, capacitance, and inductance) are distributed continuously throughout the material of the circuit.
Electrical impedance is the measure of the opposition that a circuit presents to a current when a voltage is applied.
In telecommunications and electrical engineering, electrical length (or phase length) refers to the length of an electrical conductor in terms of the phase shift introduced by transmission over that conductor at some frequency.
In electrical and electronic systems, reactance is the opposition of a circuit element to a change in current or voltage, due to that element's inductance or capacitance.
The electrical resistance of an electrical conductor is a measure of the difficulty to pass an electric current through that conductor.
An electrically short antenna is an antenna of length 2h, such that 2 \pi h\over\lambda \scriptstyle\ll 1, where λ is the free space wavelength.
An electronic circuit is composed of individual electronic components, such as resistors, transistors, capacitors, inductors and diodes, connected by conductive wires or traces through which electric current can flow.
Enderby's Wharf is a wharf and industrial site on the south bank of the Thames in Greenwich, London, associated with Telcon and other companies.
In a radio antenna, the feed line (feedline), or feeder, is the cable or other transmission line that connects the antenna with the radio transmitter or receiver.
In telecommunications, frequency-division multiplexing (FDM) is a technique by which the total bandwidth available in a communication medium is divided into a series of non-overlapping frequency bands, each of which is used to carry a separate signal.
The General Post Office (GPO) was officially established in England in 1660 by Charles II and it eventually grew to combine the functions of state postal system and telecommunications carrier.
George Ashley Campbell (November 27, 1870 – November 10, 1954) was an American engineer.
The Heaviside condition, named for Oliver Heaviside (1850–1925), is the condition an electrical transmission line must meet in order for there to be no distortion of a transmitted signal.
Helsingør, classically known in English as Elsinore, is a city in eastern Denmark.
Helsingborg (spelled Hälsingborg between 1912 and 1970) is a town and the seat of Helsingborg Municipality, Scania, Sweden.
Horta is a single municipality and city in the western part of the Archipelago of the Azores, encompassing the island of Faial.
Image impedance is a concept used in electronic network design and analysis and most especially in filter design.
In electromagnetism and electronics, inductance is the property of an electrical conductor by which a change in electric current through it induces an electromotive force (voltage) in the conductor.
An inductor, also called a coil, choke or reactor, is a passive two-terminal electrical component that stores energy in a magnetic field when electric current flows through it.
John Stone Stone (September 24, 1869 – May 20, 1943) was an American mathematician, physicist and inventor.
Joseph-Louis Lagrange (or;; born Giuseppe Lodovico Lagrangia, Encyclopædia Britannica or Giuseppe Ludovico De la Grange Tournier, Turin, 25 January 1736 – Paris, 10 April 1813; also reported as Giuseppe Luigi Lagrange or Lagrangia) was an Italian Enlightenment Era mathematician and astronomer.
Litz wire is a type of specialized multistrand wire or cable used in electronics to carry alternating current (AC) at radio frequencies.
Low frequency (low freq) or LF is the ITU designation for radio frequencies (RF) in the range of 30 kilohertz (kHz)–300 kHz.
A low-pass filter (LPF) is a filter that passes signals with a frequency lower than a certain cutoff frequency and attenuates signals with frequencies higher than the cutoff frequency.
The lumped element model (also called lumped parameter model, or lumped component model) simplifies the description of the behaviour of spatially distributed physical systems into a topology consisting of discrete entities that approximate the behaviour of the distributed system under certain assumptions.
m-derived filters or m-type filters are a type of electronic filter designed using the image method.
In physics, specifically electromagnetism, the magnetic flux (often denoted or) through a surface is the surface integral of the normal component of the magnetic field B passing through that surface.
Mihajlo Idvorski Pupin, Ph.D., LL.D. (Serbian Cyrillic: Михајло Идворски Пупин,; 4 October 1858Although Pupin's birth year is sometimes given as 1854 (and Serbia and Montenegro issued a postage stamp in 2004 to commemorate the 150th anniversary of his birth), peer-reviewed sources list his birth year as 1858. See.
A monopole antenna is a class of radio antenna consisting of a straight rod-shaped conductor, often mounted perpendicularly over some type of conductive surface, called a ground plane.
Mu-metal is a nickel–iron soft ferromagnetic alloy with very high permeability, which is used for shielding sensitive electronic equipment against static or low-frequency magnetic fields.
The City of New York, often called New York City (NYC) or simply New York, is the most populous city in the United States.
Oliver Ellsworth Buckley (August 8, 1887 – December 14, 1959) was an American electrical engineer known for his contributions to the field of submarine telephony.
Oliver Heaviside FRS (18 May 1850 – 3 February 1925) was an English self-taught electrical engineer, mathematician, and physicist who adapted complex numbers to the study of electrical circuits, invented mathematical techniques for the solution of differential equations (equivalent to Laplace transforms), reformulated Maxwell's field equations in terms of electric and magnetic forces and energy flux, and independently co-formulated vector analysis.
Operational calculus, also known as operational analysis, is a technique by which problems in analysis, in particular differential equations, are transformed into algebraic problems, usually the problem of solving a polynomial equation.
An optical fiber or optical fibre is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair.
A passband is the range of frequencies or wavelengths that can pass through a filter.
Permalloy is a nickel–iron magnetic alloy, with about 80% nickel and 20% iron content.
In electromagnetism, permeability is the measure of the ability of a material to support the formation of a magnetic field within itself.
In telecommunication and electrical engineering, a phantom circuit is an electrical circuit derived from suitably arranged wires with one or more conductive paths being a circuit in itself and at the same time acting as one conductor of another circuit.
The primary line constants are parameters that describe the characteristics of conductive transmission lines, such as pairs of copper wires, in terms of the physical electrical properties of the line.
The propagation constant of a sinusoidal electromagnetic wave is a measure of the change undergone by the amplitude and phase of the wave as it propagates in a given direction.
In a conductor carrying alternating current, if currents are flowing through one or more other nearby conductors, such as within a closely wound coil of wire, the distribution of current within the first conductor will be constrained to smaller regions.
Radiation resistance is that part of an antenna's feedpoint resistance that is caused by the radiation of electromagnetic waves from the antenna, as opposed to loss resistance (also called ohmic resistance) which generally causes the antenna to heat up.
In telecommunications, a repeater is an electronic device that receives a signal and retransmits it.
In physics, resonance is a phenomenon in which a vibrating system or external force drives another system to oscillate with greater amplitude at specific frequencies.
A resonator is a device or system that exhibits resonance or resonant behavior, that is, it naturally oscillates at some frequencies, called its resonant frequencies, with greater amplitude than at others.
Serbia (Србија / Srbija),Pannonian Rusyn: Сербия; Szerbia; Albanian and Romanian: Serbia; Slovak and Czech: Srbsko,; Сърбия.
Skin effect is the tendency of an alternating electric current (AC) to become distributed within a conductor such that the current density is largest near the surface of the conductor, and decreases with greater depths in the conductor.
In physics, a standing wave – also known as a stationary wave – is a wave which oscillates in time but whose peak amplitude profile does not move in space.
In radio engineering and telecommunications, standing wave ratio (SWR) is a measure of impedance matching of loads to the characteristic impedance of a transmission line or waveguide.
A submarine communications cable is a cable laid on the sea bed between land-based stations to carry telecommunication signals across stretches of ocean and sea.
The T-carrier is a member of the series of carrier systems developed by AT&T Bell Laboratories for digital transmission of multiplexed telephone calls.
A transatlantic telegraph cable is an undersea cable running under the Atlantic Ocean used for telegraph communications.
A transformer is a static electrical device that transfers electrical energy between two or more circuits through electromagnetic induction.
In communications and electronic engineering, a transmission line is a specialized cable or other structure designed to conduct alternating current of radio frequency, that is, currents with a frequency high enough that their wave nature must be taken into account.
Twisted pair cabling is a type of wiring in which two conductors of a single circuit are twisted together for the purposes of improving electromagnetic compatibility.
Very low frequency or VLF is the ITU designation for radio frequencies (RF) in the range of 3 to 30 kilohertz (kHz), corresponding to wavelengths from 100 to 10 kilometers, respectively.
A voice frequency (VF) or voice band is one of the frequencies, within part of the audio range, that is being used for the transmission of speech.
A waveform is the shape and form of a signal such as a wave moving in a physical medium or an abstract representation.
In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats.
Western Electric Company (WE, WECo) was an American electrical engineering and manufacturing company that served as the primary supplier to AT&T from 1881 to 1996.
The Western Union Company is an American financial services and communications company.