Glossary the BKS


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Symbol designation for ampere.
Available Bit Rate.
Abrasion Resistance
Ability of a wire, cable or material to resist surface wear.
Abrasion Stripper
More accurately described as "buffing stripper", which is a motorized device for removing flat cable insulation by means of one or two buffing wheels that melt the insulation and brush it away from the conductors.
Alternating current.
Accelerated Aging
A test that simulates long time environmental conditions in a relatively short time.
The difference between attenuation and crosstalk, measured in dB, at a given frequency (acronym for Attenuation Crosstalk Ratio). Important characteristic in networking transmission to assure that signal sent down a twisted pair is stronger at the receiving end of the cable than are any interference signals imposed on that same pair by crosstalk from other pairs.
Asymmetric Digital Subscriber Line: connection with asymmetrical downstream and upstream bandwidth.
Informal name of a digital audio standard established jointly by the AES (Audio Engineering Society) and EBU (European Broadcast Union) organizations.
Audio frequency.
Air Core
Cables that are not gel filled.
Air-Gap Dielectric
A coaxial design in which a monofilament of plastic holds the center conductor in place allowing the remainder of the dielectric to be air. Typical velocities of up to 84% can be achieved in this design.
A combination of two or more different polymers/metals. Usually combined to make use of different properties of each polymer metal.
Coated Aluminum Polyethylene.  Basic sheath.
Alternating Current (AC)
Electric Current that alternates or reverses polarity continuously. The number of alternations per second are described as cycles, (hertz or Hz).
Amplitude modulation.
Conditions existing at a test or operating location prior to energizing equipment (e.g.: ambient temperature).
American Wire Gauge (AWG)
A standard for expressing wire diameter. As the AWG number gets smaller, the wire diameter gets larger.
Current handling capability. The maximum current a conductor can carry without being heated beyond a safe limit.
A standard unit of current. Defined as the amount of current that flows when one volt of emf is applied across one ohm of resistance. An ampere of current is produced by one coulomb of charge passing a point in one second.
The Maximum value of a varying wave form.
Analog Signal
An electrical signal which varies continuously, not having discrete values. Analog signals are copies or representations of other waves in nature. An analog audio signal, for instance, is a representation of the pressure waves which make up audible sound.
Representation of data by continuously variable quantities.
To soften and relieve strains in any solid material, such as metal or glass, by heating to just below its melting point and then slowly cooling it. Annealing generally lowers the tensile strength of the material, while improving its flex life and flexibility.
American National Standards Institute.
Aluminum Steel Polyethylene.  Provides mechanical and electrical protection.
The American Society for Testing and Materials, a standards organization which suggests test methods, definitions and practices.
Asynchronous Transfer Mode
The SONET standard for a packet switching technique which uses packets of a fixed length.
The SONET standard for a packet switching technique which uses packets of a fixed length. Asynchronous Transfer Mode.
Audio Frequency
Frequencies within the range of human hearing: approximately 20 to 20,000 Hz.
A term used to describe sounds within the range of human hearing. Also used to describe devices which are designed to operate within this range (20 Hz to 20 kHz).
American Wire Gage. A wire diameter specification. The smaller the AWG number, the larger the wire diameter.
Appliance Wiring Material.

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The cable used to connect all systems of a multi-level distributed system to an intermediate system.
Metal housing providing continuity of shield through IDC connectors.
Balanced Line
A cable having two identical conductors which carry voltages opposite in polarity and equal in magnitude with respect to ground, suitable for differential signal transmission.
A device for matching an unbalanced coaxial transmission line to a balanced two-wire system. Can also provide impedance transformation, as 300 ohm balanced to 75 ohm unbalanced.

The difference between the upper and lower limits of a given band of frequencies. Expressed in Hertz.  The range of frequencies that a transmitted communications signal occupies or that a receiving system can accept.  For example, it takes more bandwidth to download a photograph in a second than to download a page of text.  Virtual reality and three-dimensional audio/visual presentations require even more.

Unit of data transmission speed meaning bits per second (500 baud=500 bits per second).
A unit that represents the logarithm of the ratio of two levels. The number of bels is equal to the logarithm sub 10 of P sub 1/P sub 2):2 logarithm sub 10 (E sub 1/E sub 2); and 2 logarithm sub 10 (I sub 1/I sub 2). See dB.
Bend Loss
A form of increased attenuation caused by (a) having an optical fiber curved around a restrictive radius of curvature or (b) microbends caused by minute distortions in the fiber imposed by externally induced perturbations.
Bend Radius
Radius of curvature that a flat, round, fiber optic or metallic cable can bend without any adverse effects.
A tape or thread used for holding assembled cable components in place.
Bit Error Rate
The number of errors occurring in a system per second. Typically less than 10e-12.
One binary digit.
Bits Per Second
The number of binary bits that can be transmitted per second - I.e. Mbps (Mega - millions), Gbps (Giga - billions).
Abbreviation for "Bayonet Neil Concelman". A coaxial cable connector used extensively in video and R. F. applications and named for its inventor.
Bonded ASP
Aluminum Steel Polyethylene where the steel is bonded to polyethylene for strength.  Filled cables for use in ducts.
Steel is bonded to polyethylene with a copolymer adhesive All STALPETH and some ASP cables are bonded.  Provides extra strength to jacket, primarily used in underground applications.
The method used to produce good electrical contact between metallic parts of any device. Used extensively in automobiles and aircraft to prevent static buildup. Also refers to the connectors and straps used to bond equipment.
A device or amplifier inserted into a line or cable to increase the voltage. Transformers may be employed to boost ac voltages. The term booster is also applied to antenna preamplifiers.
The number of binary bits that can be transmitted per second - I.e. Mbps (Mega - millions), Gbps (Giga - billions).
Bi-Phase Shift Keying.
Braid Angle
The angle between a strand of wire in a braid shield and the axis of the cable it is wound around.
A group of textile or metallic filaments interwoven to form a tubular flexible structure which may be applied over one or more wires, or flattened to form a strap.
Breakdown Voltage
The voltage at which the insulation between two conductors will fail and allow electricity to conduct or 'arc'.
The point at which a conductor or conductors are separated from a multi-conductor cable to complete circuits at various points along the main cable.
Basic Rate Interface ISDN.
The technique used to multiplex multiple networks on a single cable without interfering with each other.  Technologies that allow you to transmit or receive higher volumes of data at higher speeds.
A protective coating over an optical fiber.
Buffing Stripper
A motorized device for removing flat cable insulation by means of one or two buffing wheels that melt the insulation and brush it away from the conductors. Also called Abrasion Stripper.
Bunch Strand
Conductors twisted together with the same lay and direction without regard to geometric pattern.
Cables that are required to go underground.
Bus-bar Wire
Uninsulated tinned copper wire used as a common lead.
Butyl Rubber
A synthetic rubber with good electrical insulating properties.
A group of adjacent binary digits (8 bits).

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Symbol designation for capacitance, and Celsius.

Cable Modem
A device that enables you to hook up your PC to a local cable TV line and receive data at much faster rates than telephone modems and ISDN lines.  A strong competitor to DSL telephone service.

A group of individually insulated conductors twisted helically.

The grouping or twisting together of two or more insulated conductors to form a cable.

Coated Aluminum, Coated Steel, Polyethylene.  Provides additional strength and protection.

Canadian Electrical Code (CEC)
Canadian version of the US National Electrical Code (NEC).

Carrierless Amplitude Phase Modulation.

The ability of a dielectric material between conductors to store energy when a difference of potential exists between the conductors. The unit of measurement is the farad. Cable capacitance is usually measured in picofarads (pF).

Capacitive Crosstalk
Cable crosstalk or interference resulting from the coupling of the electrostatic field of one conductor upon one or more others.

Capacitive Reactance
The opposition to alternating current due to the capacitance of a capacitor, cable, or circuit. It is measured in ohms and is equal to 1/6.28fC where f is the frequency in Hz and C is the capacitance in farads.

Two conducting surfaces separated by a dielectric material. The capacitance is determined by the area of the surfaces, type of dielectric, and spacing between the conducting surfaces.

Carrier Strip
Also referred to as substrate. A film that is on one side of a laminated flat cable.

Coated Aluminum, Coated Steel.

Category Cables
Leoni A.G. has an extensive range high Perfromance twisted pair LAN Category cables,All Leoni A.G. products is certified to applicable international and national standards.

Rating of a cable established by TIA/EIA to indicate the level of electrical performance.

Abbreviation for Community Antenna Television.  Cable TV.

Citizens band.

Constant Bit Rate.

Closed-circuit television.

Cellular Polyethylene
Expanded or "foam" polyethylene, consists of individual closed cells of inert gas suspended in a polyethylene medium, resulting in a desirable reduction of the dielectric constant.

Center-to-Center Distance
Pitch. Nominal distance from center-to-center of adjacent conductors within a cable. When conductors are flat, pitch is usually measured from the reference edge of a conductor to the reference edge of the adjacent conductor.

The horizontal cable including the workstation outlet and patch panel in the telecommunications closet plus a maximum combined length of up to ten meters of patch cable at each end (maximum length of 100 meters).

Characteristic Impedance
In a transmission cable of infinite length, the ratio of the applied voltage to the resultant current at the point the voltage is applied. Or the impedance which makes a transmission cable seem infinitely long, when connected across the cable's output terminals.

Chrominance Signal
The portion of a composite video signal that contains the color information.

A system of conducting media designed to pass an electric current.

Circular Mil
The area of a circle one one-thousandth of an inch (.001") in diameter. By knowing the circular mil area of various conductors, they can be used to determine what conductivity and gage size various combinations will produce.

A low refractive index material that surrounds the core of an optical fiber causing the transmitted light to travel down the core and protects against surface contaminant scattering. A layer of metal applied over another. Cladding is often chosen to improve conductivity or to resist corrosion.

Central Office.

Coaxial Cable
A cylindrical transmission line comprised of a conductor centered inside a metallic tube or shield, separated by a dielectric material, and usually covered by an insulating jacket.  The kind of cable that links your cable TV provider to your home or office.  Also sometimes used by telephone companies from their telephone poles to their customers, and by businesses for local area networks.  Because of its high bandwidth, you can simultaneously receive hundreds of channels from coaxial cable.

Coil Effect
The inductive effect exhibited by a spiral-wrapped shield, especially above audio frequencies.

Color Code
A system of different colors or stripes used to identify components of cables such as individual conductors or groups of conductors.

Component Video
The unencoded output of a camera, video tape recorder, etc., whereby each red, green, and blue signal is transmitted down a separate cable. Component video systems most commonly use bundled coax as a transmission medium.

Composite Cable
Cable having conductors with two or more AWG sizes or more than one cable type.

Composite Video
The encoded output of a camera, video tape recorder, etc., whereby the red, green, blue, horizontal and vertical sync are transmitted simultaneously down one cable.

Concentric Stranding
A group of uninsulated wires twisted together and containing a center core with subsequent layers spirally wrapped around the core with alternating lay directions to form a single conductor.

The ability of a material to allow electrons to flow, measured by the current per unit of voltage applied. It is the reciprocal of resistivity.

A substance, usually metal, used to transfer electrical energy from point to point.

A tube of metal or plastic through which wire or cable can be run. Used to protect the wire or cable and, in the case of metal conduit, make it fireproof.

A device designed to allow electrical flow from one wire or cable to a device on another cable. A connector will allow interruption of the circuit or the transfer to another circuit without any cutting of wire or cable or other preparation.

Trademark of Copperweld Steel Co. for copper-clad steel conductor.

A very flexible insulated cable.

The light conducting central portion of an optical fiber with a refractive index higher than that of the cladding. The center of a cable construction. Most often applies to a coaxial cable, where the core is the center conductor and the dielectric material applied to it.

The ionization of gasses about a conductor that results when the potential gradient reaches a certain value.

The transfer of energy (without direct electrical contact) between two or more cables or components of a circuit.

How well a metal shield covers the underlying surface. Measured in percent.

Chlorinated polyethylene can be used as either a thermoplastic or thermoset. It is a tough chemical and oil-resistant material and makes an excellent jacket for industrial control cable. As a thermoset, it can be used as an oil resistant cord jacket. Other outstanding properties include low water absorption and superior crush resistance, which are important attributes in industrial control applications.

Abbreviation for cycles per second or Hertz.

Central Processing Unit.

A type of interference caused by audio frequencies from one pair being coupled into adjacent pairs. The term is also used to describe coupling at higher frequencies.

Cathode Ray Tube.

Abbreviation for Canadian Standards Association, the Canadian version of the Underwriters Laboratories.

Carrier Sense Multiple Access/Collision Detection.


Current Carrying Capacity
The maximum current a conductor can carry without being heated beyond a safe limit (ampacity).

Current Loop
A two wire transmit/receive interface.

Current, Alternating (ac)
An electric current that periodically reverses direction of electron flow. The rate at which a full cycle occurs in a given unit of time (generally a second) is called the frequency of the current.

Current, Direct (dc)
Electrical current whose electrons flow in one direction only. It maybe constant or pulsating as long as its movement is in the same direction.

Cut-through Resistance
A test to determine the ability of a material to withstand the application of blades or sharp edges without being cut.

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A component digital video recording format that conforms to the CCIR-601 standard. Records on 19 mm magnetic tape. (Often used incorrectly to indicate component digital video).

A composite digital video recording format. Records on 19 mm magnetic tape.

A composite digital video recording format. Records on 1/2" magnetic tape.

Daisy Chain
A cable assembly with three or more termination areas.

Digital Audio Video Council.


Direct Broadcast Satellite.

DC Resistance
See resistance.

Direct current.

Decibel (dB)
A decibel is one-tenth of a bel and is equal to 10 times the logarithm of the power ratio, 20 times the log of the voltage ratio, or 20 times the log of the current ratio. Decibels are also used to express acoustic power, such as the apparent level of a sound. The decibel can express an actual level only when comparing with some definite reference level that is assumed to be zero dB.

Delay Line
A transmission line or equivalent device designed to delay a wave or signal for a specific length of time.

Dual Expanded Plastic Insulated Conductor (Foam Skin).  Decreases outside diameter of cable.

Derating Factor
A multiplier used to reduce the current carrying capacity of conductors in more adverse environments.

Data Encryption Standard.

Dynamic Host Configuration Protocol.

Dielectric Breakdown
Any change in the properties of a dielectric that causes it to become conductive. Normally a catastrophic failure of an insulation because of excessive voltage.

Dielectric Constant
Also called permittivity. That property of a dielectric which determines the amount of electrostatic energy that can be stored by the material when a given voltage is applied to it. Actually, the ratio of the capacitance of a capacitor using the dielectric to the capacitance of an identical capacitor using a vacuum (which has a Dielectric Constant of 1) as a dielectric. A number which indicates the quality of a material to resist holding an electrical charge when placed between two conductors.

Dielectric Heating
The heating of an insulating material when placed in a radio-frequency field, caused by internal losses during the rapid polarization reversal of molecules in the material.

Dielectric Loss
The power dissipated in a dielectric as the result of the friction produced by molecular motion when an alternating electric field is applied.

Dielectric Strength
The voltage an insulation can withstand before it breaks down. Usually expressed as 'volts per mil'.

Dielectric Withstand Voltage
The voltage that an insulating material can withstand before breakdown occurs.

An insulating (non-conducting) medium when used in a signal-carrying design.

Digital Signal
An electrical signal which possesses two distinct states (on/off, positive/negative).

The cause of bandwidth limitations in an optical fiber. Dispersion causes a broadening of input pulses along the length of the fiber. Two major types are (a) mode dispersion caused by differential optical path lengths in a multimode fiber, and (b) material dispersion caused by a differential delay of various wavelengths of light in a wave guide material.

Any undesired change in a wave form or signal.

Distribution Cables
In a CATV system, the transmission cable between the distribution amplifier and the drop cable.

Disturbed Conductor
A conductor that receives energy generated by the field of another conductor or an external source. e.g. the quiet line.

Discrete Multitone.

Data Over Cable Service Interface Specification.

Drain Wire
A non-insulated wire in contact with parts of a cable, usually the shield, and used in the termination to that shield and as a ground connection.

Drop Cable
In a CATV system, the transmission cable from the distribution cable to a dwelling.

Digital Subscriber Line.  A technology for bringing high-bandwidth information to homes and small businesses over ordinary copper telephone lines.  A DSL line can carry both data and voice signals, with the data part of the line remaining continuously connected.  Currently competes with the cable modem in bringing broadband services to homes and small businesses.

Digital Video Broadcast.

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Voltage (electromotive force).
British terminology for zero-reference ground.
Edge Margin
Abbreviation for Electronic Field Production. Video production for commercials, television shows and other non-news purposes done outside the studio.
Electronic Industries Association (formerly RMA or RETMA).
Any material that will return to its original dimensions after being stretched or distorted.
Electromagnetic Coupling
The transfer of energy by means of a varying magnetic field. Inductive coupling.
Referring to the combined electric and magnetic fields caused by electron motion through conductors.
Electron Volt
A measure of the energy gained by an electron falling through an electric field produced by one volt.
Electrostatic Coupling
The transfer of energy by means of a varying electrostatic field. Capacitive coupling.
Pertaining to static electricity, or electricity at rest. An electric charge, for example.
Equal level Far End Crosstalk (dB) - A subtraction of attenuation from FEXT. By subtracting the attenuation, ELFEXT negates the effects of attenuation on the interference as it propagates down the cable, thus bringing it to an "equal level".
The increase in length of a wire or cable cause by longitudinal tension.
Electromotive force (voltage).
Abbreviation for electromagnetic interference.
Energy Dissipation
Loss of energy from a system due to the conversion of work energy into an undesirable form usually heat. Dissipation of electrical energy occurs when current flows through a resistance.
The capability of doing work.
Abbreviation for Electronic News Gathering.
Ethylene-propylene-diene monomer rubber. A chemically cross-linked elastomer with good electrical insulating properties and excellent flexibility at high and low temperatures. It has good insulation resistance and dielectric strength, as well as excellent abrasion resistance and mechanical properties. EPDM has better cut-through resistance than Silicone rubber, which it replaces in some applications.
Ethylene-propylene copolymer rubber. A material with good electrical insulating properties.
More than one layer of helically laid wires with the length of the lay the same for each layer.
Abbreviation for a copper refining process called Electrolytic Tough Pitch. This process produces a conductor that is 99.95% pure copper resulting in high conductivity.
Electron volt.
Expanded Polyethylene
Expanded or "foam" polyethylene, consists of individual closed cells of inert gas suspended in a polyethylene medium, resulting in a desirable reduction of the dielectric constant.
Extruded Cable
Conductors are simultaneously insulated and the cable is formed by a continuous extrusion process.

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Frequently Asked Question.
A unit of capacity that will store one coulomb of electrical charge when one volt of electrical pressure is applied.
Fire Alarm and Signal Cable, CSA (Canadian Standards Association) Cable Designation.
Abbreviation for flat conductor flat cable.
Fiber Data Distribution Interface.
Forward Error Correction.
Energy that is extracted from a high-level point in a circuit and applied to a lower level. Positive feedback reduces the stability of a device and is used to increase the sensitivity or produce oscillation in a system. Negative feedback, also called inverse feedback, increases the stability of a system as the feedback improves stability and fidelity.
Feeder Cable
In a CATV system, the transmission cable from the head end (signal pickup) to the trunk amplifier. Also called a trunk cable.
Fluorinated ethylene-propylene. A thermo-plastic material with good electrical insulating properties and chemical and heat resistance.

Composed of and/or containing iron. A ferrous metal exhibits magnetic characteristics.
Far End Crosstalk (dB) - Crosstalk induced on the pairs, measured at the "far" end of the cable.
Fiber Optics
Light transmission through optical fibers for communication and signaling.  A technology that transmits information as light pulses along a glass or plastic fiber.  Optical fiber carries much more information than conventional copper wire and is generally not subject to interference.  Most telephone company long-distance lines are optical fiber.  See RUS 1755.900.
Fiber to the home (FTTH)
A technology that provides voice, data and video services from the phone company's branch office to local customers over an all-fiber optic link.  Still in its infancy, FTTH technology is substantially more expensive and labor-intensive to install and maintain than competing technologies.
A single, separate optical transmission element characterized by core and cladding.
An area through which electric and/or magnetic lines of force pass.
Cables that are gel filled.
Nonconducting components cabled with the insulated conductors or optical fibers to impart roundness, flexibility, tensile strength, or a combination of all three, to the cable.
Flame Resistance
The ability of a material not to fuel a flame once the source of heat is removed.
Flat Cable
Also referred to as planar and/or ribbon cable. Any cable with two or more parallel conductors in the same plane encapsulated by insulating material.

Flat Conductor Cable
A flat cable with a plurality of flat conductors.
Flat Conductor
A conductor with a width-to-thickness ratio or arbitrarily 5 to 1 or greater.
Flex Life
The ability of a cable to bend many times before breaking.
The ability of a cable to bend in a short radius. The ability of a cable to lay flat or conform to a surface as with microphone cables.
Referring to a circuit which has no connection to ground.
Generic term for PVDF.
Frequency modulation.
Foam Polyethylene
Expanded or "foam" polyethylene, consists of individual closed cells of inert gas suspended in a polyethylene medium, resulting in a desirable reduction of the dielectric constant.
Flame retardant ethylene propylene is a special flame retardant version of EPDM rubber. It is designed for use as an industrial control insulation and has excellent electrical, deformation resistance, and also meets the flame retardant needs of industrial control cables.
Frequency Response
The characteristic of a device denoting the range of frequencies over which it may be used effectively.
The number of times a periodic action occurs in one second. Measured in Hertz.
Frequency, Power
Normally, the 50 or 60 hertz power available in residential areas.

FR-TPE, flame retarded thermoplastic elastomer, is a rubber-like plastic that has properties similar to rubber yet is processed as a thermoplastic. It is used as the insulation and jacket in an all TPE construction which meets UL 13 and 1277 industrial cable requirements. It has good electrical properties, abrasion resistance, colorability and flame retardancy. This compound is ideal for cold weather applications.
Frequency Shift Key.

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The physical diameter of a wire. A standard for expressing wire diameter. As the AWG number gets smaller, the wire diameter gets larger.

The increase of voltage, current, or power over a standard or previous reading. Usually expressed in decibels.

One billion.
Gigahertz (GHz)
A unit of frequency equal to one billion hertz.
Gopher Resistant Copper Alloy.  Provides shield and added protection in a single layer.
A type of optical fiber in which the refractive index of the core is in the form of a parabolic curve, decreasing toward the cladding. This type of fiber provides high bandwidth capabilities.
Ground Conductor
A conductor in a transmission cable or line that is grounded.
Ground Loop
A completed circuit between shielded pairs of a multiple pair created by random contact between shields. An undesirable circuit condition in which interference is created by ground currents when grounds are connected at more than one point.
Ground Potential
The potential of the earth. A circuit, terminal, or chassis is said to be at ground potential when it is used as a reference point for other potentials in the system.
An electrical connection between a circuit and the earth. Also refers to a conductor connected to earth. In some instances, can refer to a central metallic point designated as having "zero" potential.

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Symbol designation for magnetic intensity and henry.

Thermoplastic fluoropolymer material with excellent chemical resistance, electrical properties, thermal characteristics, and impact resistance.

Haloarrest I
Haloarrest I is a non-halogenated flame retarded thermoplastic polyolefin with excellent low smoke and flame properties. It is used as a jacket over the XLPE insulated singles (non-XHHW), and the entire construction meets the UL 13 and 1277 specifications as a non-halogenated PLTC/TC cable. Haloarrest I meets the European Specifications on acid gas evolution and % Halogen content. This jacket can also be used with XHHW conductors for wet ratings.

A flat cable or group of cables, usually with many breakouts with the wire ends prepared for termination or terminated to connectors and ready to install.

High bit-rate Digital Subscriber Line.

The amount by which a cable ACR exceeds 10 dB. The TIA/EIA 568B standard states a minimum of 10 dB of ACR is required for Category 5 certification.

A practical unit of inductance that will produce a voltage drop of one volt when the current changes at the rate of one ampere per second (abbreviated H).

Hertz (Hz)
The number of changes in polarity which a signal makes in one second. An indication of frequency. Replaces cycles-per-second.

Heterogeneous Insulation
A cable insulating system composed of two or more layers of different insulating materials.

High frequency.

Hybrid Fiber/Coaxial.

High Frequency
The band from 3 to 30 MHz in the radio spectrum, as designated by the Federal Communications Commission.

Homogeneous Insulation
A complete cable insulation structure whose components cannot be identified as layers of different materials.

Hook-Up Wire
Single conductor wire with various types of insulation.

Horizontal Cable
Cable used to go between the workstation outlet and the telecommunications closet.

High-Speed Cable Data Service.

Hypertext Markup Language.

Hypertext Transmission Protocol.

A term used to describe the 60- or 120 cycle per second noise present in the sound of some communications equipment. Usually hum is the result of undesired coupling to a 60 cycle source or to the defective filtering of 120 cycle ripple output of a rectifier.

A DuPont trade name for a synthetic rubber (chlorosulfonated polyethylene) used as insulating and jacketing material for wire and cable.

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Symbol used to designate current.
I/O Interconnection
Input/Output interface to the "outside world."
Formula for power in watts, where I=current in amperes, R=resistance in ohms.
Insulated Cable Engineers Association.
Abbreviation for Insulation Displacement Contact.

ISDN Digital Subscriber Line.
Institute of Electrical and Electronic Engineers.
Internet Engineering Task Force.
Abbreviation for Interrupted Feed Back, a monitoring scheme often used in television where the feed of program audio can be interrupted with directions, cues or other information.
Internet Group Management Protocol.
Impedance Match
A condition whereby the impedance of a particular circuit cable or component is the same as the impedance of the circuit, cable, or device to which it is connected.
Impedance Matching Sub
A section of transmission line or pair of conductors cut to match the impedance of a load. Also called matching sub.
Impedance Matching Transformer
A transformer designed to match the impedance of one circuit to that of another.
The total opposition that a circuit offers to the flow of alternating current or any other varying current at a particular frequency. It indicates the ideal transfer of signal from one piece of equipment to another. It is measured in ohms.
Impedance, Characteristic
In a transmission cable of infinite length, the ratio of the applied voltage to the resultant current at the point the voltage is applied. Or the impedance which makes a transmission cable seem infinitely long, when connected across the cable's output terminals.
Impedance, High
Generally, the area of 25,000 ohms or higher.
Impedance, Low
Generally, the area of 1 through 600 ohms.
Index Edge
"Reference Edge".
The property of wire which stores electrical current in a magnetic field around the wire. By coiling wire, the effect can be intensified. It is measured in Henrys.
Induction Heating
Heating a conducting material by placing it in a rapidly changing magnetic field. The changing field induces electric currents in the material and I2R (I to the second R) losses account for the resultant heat.
The phenomenon of a voltage, magnetic field, or electrostatic charge being produced in an object by lines of force from the source of such fields.
Inductive Crosstalk
Crosstalk resulting from the coupling of the electromagnetic field of one conductor upon another.
Injection Laser Diode
Sometimes called the semiconductor diode. A laser in which the lasing occurs at the junction of n-type and p-type semiconductor materials.
Integrated Network Management System.
A signal (or power) which is applied to a piece of electric apparatus or the terminals on the apparatus to which a signal or power is applied.
Insertion Loss
A measure of the attenuation of a cable or component by determining the output of a system before and after the device is inserted into the system.
Insulation Displacement Connector (IDC)
A mass termination connector for flat cable with contacts that displace the conductor insulation to complete termination.
Insulation Stress
The molecule separation pressure caused by a potential difference across an insulator. The practical stress on insulation is expressed in volts per mil.
A material having good dielectric properties which is used to separate close electrical components, such as cable conductors and circuit components.
The region where two systems or a major and a minor system meet and interact with each other.
Disturbances of an electrical or electromagnetic nature that introduce undesirable responses into other electronic equipment.
Intermediate Frequency
A frequency to which a signal is converted for ease of handling. Receives its name from the fact that it is an intermediate step between the initial and final conversion or detection stages.

Ionization Voltage
The potential at which a material ionizes. The potential at which an atom gives up an electron.
The formation of ions. Ions are produced when polar compounds are dissolved in a solvent and when a liquid, gas, or solid is caused to lose or gain electrons due to the passage of an electric current.
Internet Protocol.
IP Over Cable Data Network working group of the IETF.

IR Drop
The designation of a voltage drop in terms of current and resistance.

Insulation Resistance.
Inter Relay Chat.
Ignition radiation suppression.
Integrated Services Digital Network.  An alternative to telephone modems that allows digital transmission over ordinary telephone copper wire and other media.  Home and business users can get highly graphic Web pages more quickly through ISDN adapters than through dial-up connections.
International Standards Organization.
The ability of a circuit or component to reject interference, usually expressed in dB.
Internet Service Provider.
Instructional Television Fixed Service.
International Telecommunications Union.

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Pertaining to wire and cable, the outer protective covering (may also provide additional insulation).

A short length of conductor or flat cable used to make a connection between terminals or around a break in a circuit, or between circuit boards.

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1000 electron volts.

One thousand.

Tensile strength in thousands of pounds per square inch.

Kilovolt (1000 volts).

Kilovolt ampere.


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Symbol for inductance.

Laminated Cable
Insulated or uninsulated wires which are encapsulated by two sheets of laminate material to maintain a predetermined pitch.

A data network connecting any number of users, intended to serve a small area.  Local Area Network.  A group of computers and associated devices that share a common communications line and typically share the resources of a single processor or server within a small geographic area.

A coherent source of light with a narrow beam and a narrow spectral bandwidth (about 2nm).

Lay Direction
The direction of the progressing spiral twist in a cable while looking along the axis of the cable away from the observer. The lay direction can be either "left" or "right".

The length measured along the axis of a wire or cable required for a single strand (in stranded wire) or conductor (in cable) to make one complete turn about the axis of the conductor or cable. In a twisted pair cable, the lay length is the distance it takes for the two wires to completely twist around each other.

Lead Dress
The placement or routing of wiring and component leads in an electrical circuit.

The cable that provides the path for r-f energy between the antenna and the receiver or transmitter.

The undesirable passage of current over the surface of or through an insulator.

Local Exchange Carrier.

A measure of the difference between a quantity or value and an established reference.

Low frequency.

Light Emitting Diode (LED Source)
A semiconductor device that emits incoherent light formed by the P-N junction. Light intensity is roughly proportional to electrical current flow.

The ability of a cable to lay flat or conform to a surface as with microphone cables. The ability of a cable to bend in a short radius.

Line Drop
A voltage loss occurring between any two points in a power or transmission line. Such loss, or drop, is due to the resistance, reactance, or leakage of the line.

Line Equalizer
A reactance (inductance and/or capacitance) connected in series with a transmission line to alter the frequency-response characteristics of the line.

Line Level
Refers to the output voltage level of a piece of electronic equipment. Usually expressed in decibels (e.g.. 0dBv).

Line Voltage
The value of the potential existing on a supply or power line.

The horizontal cable including the workstation outlet and patch panel in the telecommunications closet plus two meters of cable at each end for testing.

Local Multipoint Distribution Service

A device that consumes power from a source and uses that power to perform a function.

Loaded Line
A transmission line that has lumped elements (inductance or capacitance) added at uniformly spaced intervals. Loading is used to provide a given set of characteristics to a transmission line.

A transmission line that has lumped elements (inductance or capacitance) added at uniformly spaced intervals. Loading is used to provide a given set of characteristics to a transmission line.

Local Area Network
A data network connecting any number of users, intended to serve a small area.

Long-wire Antenna
Any conductor length in excess of one-half of a wavelength. In a residential television installation, a horizontal run or unshielded lead-in will act as a long-wire antenna and introduce additional signal on top of the regular antenna signal causing ghosts.

Energy or signal lost without accomplishing useful work.

Having poor efficiency.

Low Frequency
A band of frequencies extending form 30 to 300 kHz in the radio spectrum, designated by the Federal Communications Commission.

Luminance Signal
The portion of the composite video signal that represents the brightness or the black and white information.

Mon top


Mutual inductance. The abbreviation for mega or 1 million. And also indicates 1000 (one thousand) feet in the wire industry. m=abbreviation for milli or one-thousandth.

This notation represents 1000 feet.

milliampere (one-thousandth of an ampere).

Media Access Control (layer of OSI Reference Model).

A data network intended to serve the area of a city or an area of similar size.

Manufacturing Automation Protocol
A manufacturing automation protocol based on IEEE 802.4 standards.

A manufacturing automation protocol based on IEEE 802.4 standards.

Distance between reference edge of cable and nearest edge of first conductor or center of first conductor.

The process of simultaneously terminating all conductors in a single operation.

Matte Finish PVC
A special formulation of PVC which very closely looks and feels like rubber.

Abbreviation for Master Antenna Television.


Mega bits per second - the number of bits, in millions, transmitted per second.

Multimedia Cable Network System Partners Ltd.

Multichannel Multipoint Distribution Service.

Prefix meaning million.

Megahertz (MHz)
Unit of frequency equal to one million hertz (one million hertz per second).

Metropolitan Area Network
A data network intended to serve the area of a city or an area of similar size.

Microfarad (one-millionth of a farad).

The unit of conductance equal to the reciprocal of the unit of resistance (ohm).


Prefix meaning one-millionth.

One-millionth of a farad (uf, ufd, mf, and mfd are common abbreviations).

One-millionth of a microfarad (uuf, uufd, mmf, mmfd are common abbreviations). Also, a picofarad (pf, pfd).

Millionth of a meter.

Noise caused by mechanical excitation of a system component. In a single-conductor microphone cable, for example, microphonics can be caused by the shield rubbing against the dielectric as the cable is flexed.

A unit of length equal to one thousandth of an inch (.001").

Prefix meaning one-thousandth.

Multichannel Multipoint Distribution Service.

A single electromagnetic wave traveling in an optical fiber.

Device that converts signals in one form to another form compatible with another kind of equipment.

Altering the characteristics of a carrier wave to convey information. Modulation techniques include amplitude frequency, phase, plus many other forms of on-off digital coding.

Molded Cable
Cable assemblies with molded connectors on one or both ends.

Mono Filament
A single strand filament as opposed to a braided or twisted filament.

Multiple System Operator.

Simple Mail Transfer Protocol.

Multi-Conductor Cable
Cable with more than one conductor.

A technique for putting two or more signals into a single channel.

Mutual Capacitance
Capacitance between two conductors when all other conductors are connected together and grounded.

Millivolt (one-thousandth of a volt).

DuPont trademark for polyethylene terephtalate (polyester) film.

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Nanometer (nm)
One billionth of a meter.

One billionth of a second.

Network Access Point.

National Electrical Code (NEC)
A publication of the National Fire Protection Association (NFPA) which outlines requirements for electrical wiring and building construction. Also called the NEC.

Butadiene-acrylonitrile copolymer rubber, a material with good oil and chemical resistance.

A publication of the National Fire Protection Association (NFPA) which outlines requirements for electrical wiring and building construction. Also called the NEC.

National Electrical Manufacturers Association.
A synthetic rubber with good resistance to oil, chemical, and flame. Also called polychloroprene.

A network is a method of data communications between computers.

Near end Crosstalk (dB) - Crosstalk induced on the pairs, measured at the end "near" the transmitter.

National Fire Protection Association.

One half byte (4 bits).
Network Operations Center.

In a cable or circuit, any extraneous signal which tends to interfere with the signal normally present in or passing through the system.
DuPont trademark for a temperature-resistant, flame-retardant nylon.

Non-Paired Cable
Cable with two or more cabled conductors that are not in a paired configuration.
Area that a cable can be installed in a building that is not used for air return.
The removal of the web section between conductors of a flat cable to aid in stripping, slitting, and termination.

NTSC (National Television Systems Committee)
Organization that formulated standards for the current American television system. Also describes the system of color telecasting which is used in Japan, Thailand, and parts of South America. NTSC television uses a 3.579545 MHz subcarrier whose phase varies with the instantaneous hue of the televised color and whose amplitude varies with the instantaneous saturation of the color. NTSC employs 525 lines per frame, 30 frames per second and 59.94 fields per second.
Numerical Aperture (NA)
A measure of the angular acceptance for a fiber. It is approximately the sine of the half-angle of the acceptance cone.
An abrasion-resistant thermoplastic with good chemical resistance.

Orthogonal Frequency Division Multiplexing.
Abbreviation for oxygen-free, high conductivity copper. It has 99.95% minimum copper content and an average annealed conductivity of 101% compared to standard copper.

The unit of electrical resistance. The value of resistance through which a potential difference of one volt will maintain a current of one ampere.

Ohm's Law
Stated E=IR, I=E/R or R=E/I, the current I in a circuit is directly proportional to the voltage E, and inversely proportional to the resistance R.
Optical Waveguide Fiber
A transparent filament of high refractive index core and low refractive index cladding that transmits light.

Open System Interconnect (Model for networking protocols).

Operations Support Systems.
The useful power or signal delivered by a circuit or device.

Extremely reactive form of oxygen, normally occurring around electrical discharges and present in the atmosphere in small but active quantities. In sufficient concentrations is can break down certain rubber insulations under tension (such as a bent cable).

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Paired Cable
Cable with conductors cabled in groups of two.

PAL (Phase Alternate Line)
PAL is a European color TV system featuring 625 lines per frame, 25 frames and 50 fields per second. Used mainly in Europe, China, Malaysia, Australia, New Zealand, the Middle East, and parts of Africa. PAL-M is a Brazilian color TV system with 525 lines per frame, 30 frames and 60 fields per second.

Parallel Circuit
A circuit in which the identical voltage is presented to all components, with current dividing among the components according to the resistances or the impedances of the components.

Parallel Digital
Digital information that is transmitted in parallel form. Often used informally to refer to parallel digital television signals.

Polyethylene Aluminum Steel Polyethylene.  provides additional lightning and gopher protection.

A flexible piece of cable terminated at both ends with plugs. Used for interconnecting circuits on a patchboard.

Personal Computer.


The maximum instantaneous value of a varying current or voltage.

Peel Strength
The force necessary to separate two adjacent conductors of a bonded or laminated flat cable.

The uniformly spaced cable impedance variations that result in reflections of a signal. The distance between them is the wavelength most affected. Multiples and division of that frequency are also affected. Even very slight variations, which appear over and over in a construction, can have major effects on signal integrity because of periodicity.

Phase Shift
A change in the phase relationship between two alternating quantities.

An angular relationship between waves.

Photodetector (Receiver)
Convects light energy to electrical energy. The silicon photo diode is most commonly used for relatively fast speeds and good sensitivity in the 0.75 micron to 0.95 micron wavelength region. Avalanche photodiodes (APD) combine the detection of optical signals with internal amplification of photo-current. Internal gain is realized through avalanche multiplication of carriers in the junction region. The advantage in using an APD is its higher signal-to-noise ratio, especially at high bit rates.

Physical (layer of OSI Reference Model).

Physical Layer
The actual portion of a network that is used to physically connect computers of a network and over which the data is transmitted - the cable.

Plastic Insulated Conductor.  Provides strong insulation.

Any device which is capable of transforming a measurable quantity of intelligence (such as sound) into relative electrical signals (e.g., a microphone).


One billionth of a farad. A micromicrofarad. Abbreviation pF or mmF.

A photodetector used to convert optical signals to electrical signals in a receiver.

Nominal distance from center-to-center of adjacent conductors within a cable. When conductors are flat, pitch is usually measured from the reference edge of a conductor to the reference edge of the adjacent conductor. Spacing.

Planar Cable
Also referred to as flat and/or ribbon cable. Any cable with two or more parallel conductors in the same plane encapsulated by insulating material.

High polymeric substances, including both natural and synthetic products that are capable of flowing under heat and pressure, called thermoplastics. Unlike rubber and other thermoset compounds, plastics can be remelted and reused.

A chemical added to plastics to make them softer and more flexible.

A compartment or chamber to which one or more air ducts are connected and that forms part of the air distribution system.

A male housing with male or female contacts.

Point-to-Point Wiring
Wiring that consists of continuous conductors terminated at each end to circuit destination.

The orientation of a flat cable or a rectangular connector. e.g., for gray flat cable, the colored edge indicating the number one conductor.

A type of synthetic rubber often blended with other synthetic rubbers to improve their properties.

A thermoplastic material having excellent electrical properties. Low dielectric constant, a stable dielectric constant over all frequencies, very high insulation resistance. In terms of flexibility, polyethylene can be rated stiff to very hard, depending on molecular weight and density - low density being the most flexible and the high-density, high-molecular weight formulation being very hard. Moisture resistance is rated excellent.

A substance made of many repeating chemical units or molecules. The term polymer is often used in place of plastic, rubber, or elastomer.

Any of the polymers and copolymers of the ethylene family of hydrocarbons, such as polyethylene and polypropylene.

A thermoplastic similar to polyethylene but stiffer and having a higher softening point (temperature). This material is primarily used as an insulation material. Typically, it is harder than polyethylene. This makes it suitable for thin wall insulations. The dielectric constant is 2.25 for solid and 1.55 for cellular designs.

Polyurethane (PUR)
Broad class of polymers noted for good abrasion and solvent resistance. Can be in solid or cellular form. This thermoplastic material is used primarily as a cable jacket material. It has excellent oxidation, oil, and ozone resistance. Some formulations also have good flame resistance. It is a hard material with excellent abrasion resistance. It has outstanding "memory" properties, making it an ideal jacket material for retractile cords.

Polyvinyl chloride
A general purpose thermoplastic used for wire and cable insulation and jackets.

Portable Cordage
Cable with two or more twisted conductors for flexible applications.  Also called flexible cord.

Plain Old Telephone Service.  Means just what it says.  Sometimes used in discussions of new telephone technologies in which the question of whether and how existing voice transmission for ordinary telephone communication can be accommodated.  For example, DSL and ISDN provide part of their channels for POTS, while using most of their bandwidth for digital data transmission.

Sealing by filling with a substance to exclude moisture.

Power Loss
The difference between the total power delivered to a circuit, cable, or device and the power delivered by that device to a load.

Power Ratio
The ratio of power appearing at the load to the input power. Expressed in dB.

The amount of work per unit of time. Usually expressed in watts and equal to the formula for power in watts. (I to the second power times R).


Point-to-Point Protocol.

Precision Video
Video coaxial cables having very tight electrical tolerances in impedance, velocity of propagation, attenuation and structural return loss. Used in high quality applications such as live broadcast in network studios and pre- or post-production facilities.

Premise Cabling
Refers to the entire cabling system used for voice, data, video and power on a user's premise.  For Local Area Networks, the cabling of choice includes unshielded twisted pairs (UTP), fiber optic and coaxial cables.  Of these, the UTP market is the largest, with greatest demand for cables with four pairs that meet certain standards of performance, such as Category 5 and Category 5e.

Primary Rate Interface ISDN.

Propagation Delay
Time required for a signal to pass from the input to the output of a device.

Pseudo Random NRZ
A wave form of binary signals that may be used in a computer system. It is called NRZ, Non-Return to Zero, because the voltage does not return to zero.

Public Switched Telephone Network.

A current or voltage which changes abruptly from one value to another and back to the original value in a finite length of time. Used to describe one particular variation in a series of wave motions.

Packaging of finished wire or cable.

Polyvinyl chloride. Sometimes referred to as vinyl.  Fire resistant.

Polyvinylidene Fluoride.

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Quandrature Amplitude Modulation.

Quality of Service.

Quaternary Phase Shift Keying.

A four conductor cable. Also called "star quad".

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Symbol for resistance.

Radio Frequency (RF)
Radio-frequency. Usually considered to be frequencies ranging from 1 MHz to 3GHz.  Used to transmit information from point to point over the airwaves or down coaxial cable.

Random Access Memory.

Rated Temperature
The maximum temperature at which an electric component can operate for extended periods without loss of its basic properties.

Rated Voltage
The maximum voltage at which an electric component can operate for extended periods without undue degradation or safety hazard.

Regional Data Center.

A measure of the combined effects of capacitance and inductance on an alternating current. The amount of such opposition varies with the frequency of the current. The reactance of a capacitor decreases with an increase in frequency; the opposite occurs with an inductance.

An electronic package that converts light energy to electrical energy in a fiber optic system.

A female housing with male or female contacts.

Reference Edge
Edge of cable or conductor from which measurements are made. Sometimes indicated by a thread, identification stripe, or printing. Conductors are usually identified by their sequential position from the reference edge, with number one conductor closest to this edge.

Reflection Loss
The part of a signal which is lost due to reflection of power at a line discontinuity.

The change in direction (or return) of waves striking a surface. For example, electromagnetic energy reflections can occur at an impedance mismatch in a transmission line, causing standing waves.

Refractive Index
The ratio of light velocity in a vacuum to its velocity in the transmitting medium.

Alignment of one object with relation to another. In flat cables it involves aligning conductors with contacts or solder pads. Also called register.

A receiver and transmitter combination used to regenerate an attenuated signal.

In dc circuits, the opposition a material offers to current flow, measured in ohms. In ac circuits, resistance is the real component of impedance, and may be higher than the value measured at dc.

An ac circuit condition in which inductive and capacitive reactances interact to cause a minimum or maximum circuit impedance.

Retractile Cord
A cord having specially treated insulation or jacket so that it will retract like a spring. Retractibility may be added to all or part of a cord's length.

Radio Frequency.


Abbreviation for Ratio Frequency Interference.

Request for Proposals.

"RG" is the abbreviation for "radio guide," a military designation for a coaxial cable, and "U" stands for "universal."

Abbreviation for the three parts of color video signal: red, green and blue, and also refers to multi-coaxial cables carrying these signals.

Ribbon Cable
A flat cable made with parallel round conductors in the same plane. Also referred to as planar and/or flat cable. Any cable with two or more parallel conductors in the same plane encapsulated by insulating material.

Ringing Out
The process of locating or identifying specific conductor paths by means of passing a current through selected conductors.

Modular telecommunications connector.


Rope Strand
A conductor composed of groups of twisted strands.

The path followed by a cable or conductor.

Resource Reservation Protocol.

Real-Time Transport Protocol.

Rubber (Wire Insulation)
A general term used to describe wire insulations made of thermosetting elastomers, such as natural or synthetic rubbers, neoprene, Hypalon, butyl rubber, and others.

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Storage Area Networks (SAN) are dedicated storage networks.

Society of Automotive Engineers.

A copolymer of styrene and butadiene. Also GR-S or Buna-S. Most commonly used type of synthetic rubber.

Synchronous Code Division Multiple Access.

Symmetric Digital Subscriber Line.

Aluminum Shield. Sealed Aluminum.

The characteristic of a material that extinguishes its own flame after the igniting flame is removed.

Undulated core with aluminum, polyethylene and a support strand.  For aerial use.

In wire industry terminology, a material possessing electrical conductivity that falls somewhere between that of conductors and insulators. Usually made by adding carbon particles to an insulator. Not the same as semiconductor materials such as silicon, germanium, etc. Used for making transistors and diodes.

Pertaining to wire and cable, a layer of insulating material such as textile, paper, Mylar, etc., which is placed between a conductor and it s dielectric, between a cable jacket and the components it covers, or between various components of a multiple-conductor cable. It can be utilized to improve stripping qualities, flexibility, or can offer additional mechanical or electrical protection to the components it separates.

Serial Digital (SDI)
Digital information that is transmitted in serial form. Often used informally to refer to serial digital television signals.

Series Circuit
A Circuit in which the components are arranged end to end to form a single path for current.

Serve Shield
A metallic shield consisting of several strands of wire, helically wound around a cable core.

Single-pair High bit-rate Digital Subscriber Line.

Pertaining to wire and cable, the outer protective covering (may also provide additional insulation).

Shield Coverage
The optical percentage of a cable actually covered by shielding material.

Shield Effectiveness
The relative ability of a shield to screen out undesirable interference. Frequently confused with the term shield coverage.

Shield Percentage
The percentage of physical area of a circuit or cable actually covered by shielding material.

A tape, serve or braid (usually copper, aluminum, or other conductive material) placed around or between electric circuits or cables or their components, to prevent signal leakage or interference.

Shielded Armored
Types of Shield: Aluminum, Aluminum/Steel, Gopher, and Copper.  Cables that require some sort of shield.

Signal Conductor
A conductor in a transmission cable or line that carries electrical signals.

Any visible or audible indication which can convey information. Also, the information conveyed through a communication system.

General Electric trademark for a material made from silicone and oxygen. Can be in thermosetting elastomer or liquid form. The thermosetting elastomer form is noted for high heat resistance. This is a very soft thermoset insulation. It has excellent electrical properties plus ozone resistance, low moisture absorption, weather resistance, and radiation resistance. It typically has low mechanical strength and poor scuff resistance.

Single Mode Fiber
A fiber wave guide in which only one mode will propagate. The fiber has a very small core diameter of approximately 8 micro meters. It permits signal transmission at extremely high bandwidths and is generally used with laser diodes.

Unbalanced, such as grounding one side of a circuit or transmission line.

Varying in proportion to the sine of an angle or time function. Ordinary alternating current is sinusoidal.

Skew Rays
A ray that does not intersect the fiber axis. Generally, a light ray that enters the fiber core at a very high angle.

Skin Effect
The tendency of alternating current to travel only on the surface of a conductor as its frequency increases.

Snake Cable
A name given to individually shielded or individually shielded and jacketed, multi-pair audio cables. Used in the connection of multi-channel line level audio equipment.

Simple Network Management Protocol.

Signal to Noise Ration. Commonly used interchangeably with ACR - the difference between attenuation and crosstalk, measured in dB, at a given frequency (acronym for Attenuation Crosstalk Ratio). Important characteristic in networking transmission to assure that signal sent down a twisted pair is stronger at the receiving end of the cable than are any interference signals imposed on that same pair by crosstalk from other pairs.

Synchronous Optical Network.

The device (usually LED or laser) used to convert an electrical information-carrying signal into a corresponding optical signal for transmission by an optical wave guide.

The distance between the centers of two adjacent conductors. Pitch.

The distance between the center of the first conductor and the center of the last conductor in a flat cable.

Spectral Bandwidth
The difference between wavelengths at which the radiant intensity of illumination is half its peak intensity.

Frequencies that exist in a continuous range and have a common characteristic. A spectrum may be inclusive of many spectrums (e.g., the electromagnetic radiation spectrum includes the light spectrum, radio spectrum, infrared spectrum, etc.).

Speed of Light ( c )
2.998 x 10 (to the power of 8) meters per second.

A device that divides a high bandwidth signal into two or more lower bandwidth signals, each carrying a selected frequency range.  Users connected to a DSL line, for example, may have a splitter installed at their home or business to divide the incoming signal into low frequencies to send to their phone and high frequencies for data to the computer.

Standing Wave Ratio (SWR)
A ratio of the maximum amplitude to the minimum amplitude of a standing wave stated in current or voltage amplitudes.

Standing Wave
The stationary pattern of waves produced by two waves of the same frequency traveling in opposite directions on the same transmission line. The existence of voltage and current maxima and minima along a transmission line is a result of reflected energy from an impedance mismatch.

Star Quad
Term given to 4-conductor microphone cables where the conductors are spiraled together. Which, when connected in an "x" configuration, greatly increases common mode noise rejection.

Static Charge
An electrical charge that is bound to an object. An unmoving electrical charge.

Stay Cord
A component of a cable, usually of high tensile strength, used to anchor the cable ends at their points of termination and keep any pull on the cable from being transferred to the electrical conductors.

Step Insulated
Process of applying insulation in two layers. Typically used in shielded networking cables such that the outer layer of insulation can be removed and remaining conductor and insulation can be terminated in a RJ-45 type connector.

Step-index Fiber
An optical fiber in which the core is of a uniform refractive index with a sharp decrease in the index of refraction at the core/cladding interface.

Shielded Twisted Pair(s).

Strain Gauge
A device for determining the amount of strain (change in dimensions) when a stress is applied.

A single uninsulated wire.

Stranded Conductor
A conductor composed of groups of uninsulated wires.

To remove insulation from a cable or wire.

Stripping Groove
The controlled thinning of the lamination between two conductors in a flat cable to allow easy hand separation. Tear feature.

Structural Return Loss (SRL)
The magnitude of internal cable reflections, measured in dB.

A temporary and relatively large increase in the voltage or current in an electric circuit or cable. Also called transient.

Abbreviation for super VHS. A video format in which the two parts of the VHS video signal, the chrominance and luminance, are transmitted separately providing for better picture resolution with less noise.

Testing the frequency response, or attenuation over frequency, of a cable by generating a voltage whose frequency is varied through a given frequency range and observing or graphing the results.

Ton top


Transmission Control Protocol/Internet Protocol.

Time Division Multiple Access.

Tear Feature
The controlled thinning of the lamination between two conductors in a flat cable to allow easy hand separation.

Teflon (R)
DuPont Company trademark for fluorocarbon resins. (FEP - Fluorinated ethylene-propylene. A thermo-plastic material with good electrical insulating properties and chemical and heat resistance.). (TFE - Tetrafluoroethylene. A thermoplastic material with good electrical insulating properties and chemical and heat resistance.). It is not suitable where subjected to nuclear radiation and does not have good high voltage characteristics. FEP Teflon is extrudable in a manner similar to PVC and polyethylene. This means that long wire and cable lengths are available. TFE Teflon is extrudable in a hydraulic ram type process. Lengths are limited due to amount of material in the ram, thickness of the insulation, and preform size. TFE must be extruded over a silver- or nickel-coated wire. The cost of Teflon is approximately 8 to 10 times more per pound than PVC compounds.

Fluorocopolymer thermoplastic material has excellent electrical properties, heat resistance, chemical resistance, toughness, radiation resistance, and flame resistance.

Temperature Rating
The maximum temperature at which the insulating material may be used in continuous operation without change of its basic properties.

Tensile Strength
The pull stress required to break a bare wire.

Tetrafluoroethylene. A thermoplastic material with good electrical insulating properties and chemical and heat resistance.

Thermal Rating
The temperature range in which a material will perform its function without undue degradation.

A material which will soften, flow, or distort appreciably when subjected to sufficient heat and pressure. Examples are polyvinyl chloride and polyethylene.

A material which will not soften, flow, or distort appreciably when subjected to heat and pressure. Vulcanizable. Examples are rubber and neoprene.

Telecommunications Industry Association. Body which authored the TIA/EIA 568A "Commercial Building Telecommunications Wiring Standard" in conjunction with EIA.

"Commercial Building Telecommunications Wiring Standard defines a generic telecommunications wiring system for commercial buildings that will support a multi-product, multi-vendor environment. It also provides direction for the design of telecommunications products for commercial enterprises.

A type of electrical conductor comprised of a number of tiny threads, each thread having a fine, flat ribbon of copper or other metal closely spiraled about it. Used for small size cables requiring limpness and extra-long flex life.

Topcoated Wire
Conductor produced by applying a layer of tin over a stranded bare copper conductor holding the strands together allowing easier soldering and preventing the fraying of strands.

Twisted Pair-Physical Medium Dependent.

A device for converting mechanical energy to electrical energy.

Transfer Impedance
For a specified cable length, transfer impedance relates to a current on one surface of a shield to the voltage drop generated by this current on the opposite surface of the shield. Transfer impedance is used to determine shield effectiveness against both ingress and egress of interfering signals. Cable shields are normally designed to reduce the transfer of interference - hence, shields with lower transfer impedance are more effective than shields with higher transfer impedance.

Transmission Line Cable
Two or more conductors placed within a dielectric material in such a way as to control the electrical characteristics.

Transmission Line
An arrangement of two or more conductors, a coaxial cable, or a waveguide used to transfer signal energy from one location to another.

The electronic package that converts electrical energy to light energy in a fiber optic system.

Triad Cable
Cable with three twisted conductors.

Triaxial Cable
A cable construction having a conductor, and two isolated braid shields, all insulated from each other.

Triboelectric Noise
Noise generated in a shielded cable due to variations in capacitance between the shield and conductors as the cable is flexed.

Trunk Cable
In a CATV system, the transmission cable from the head end (signal pickup) to the trunk amplifier. Also called a feeder cable.

A contractual arrangement in which one party designs and installs a system and "turns over the keys" to another party who will operate the system.

TV Receive Only.

Twinax Cable
Cable with two twisted conductors with established electrical properties (one pair=twinax).

A transmission line having two parallel conductors separated by insulating material. Line impedance is determined by the diameter and spacing of the conductors and the insulating material and is usually 300 ohms for television receiving antennas.

Twisted Pair
Two lengths of insulated conductors twisted together.  the traditional method for connecting home and many business computers to the telephone company.  Gets its name because two insulated copper wires are twisted together, both of which are needed for each connection.  In commercial environments, performance of data transmission can be improved by adding a composite tape to the wire.  This is known as shielded twisted pair.

Two pair premise wiring
Refers to the two pairs of voice grade (low bandwidth) twisted pair wire installed in most homes since the 1950s.  The extra pair makes it possible for you to add another line when you need it.

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Abbreviation for ultra high frequency, 300 to 3,000MHz

Abbreviation for Underwriters Laboratories, a nonprofit organization which tests and verifies construction and performance of electronic parts and equipment, including wire and cable.

Unsoldered Mechanical Protection - Additional steel and polyethylene over inner polyethylene jacket.  Provides additional mechanical protection.

Unbalanced Line
A transmission line in which voltages on the two conductors are unequal with respect to ground. A coaxial cable is a common type of unbalanced line.

A conductor with more than one layer of helically laid wires with the direction of lay and length of lay the same for all layers.

Unshielded Twisted Pair(s).

Von top



Volt-ampere. A designation of power in terms of voltage and current.

Variable Constellation/Multi-Tone Modulation.

Vary high bit-rate Digital Subscriber Line.

Velocity of Propagation (VP)
The transmission speed of electrical energy in a length of cable compared to speed of light in free space. Usually expressed as a percentage.

Abbreviation for very high frequency, 30 to 300 HMz as designated by the Federal Communications Commission.

Abbreviation for Video Home System. VHS is a trademark of Panasonic, Inc.

Pertaining to picture information in a television system.

Abbreviation for very low frequency, 10 to 30 kHz.

A unit of electromotive force.

Voltage Drop
The voltage developed across a component or conductor by the current flow through the resistance or impedance of the component or conductor.

Voltage Rating
The highest voltage that may be continuously applied to a cable construction in conformance with standards or specifications.

Voltage Standing Wave Ratio (VSWR)
The ratio of the transferring signal voltage as compared to reflected signal voltage measured along the length of a transmission line.

Electrical potential of electromotive force expressed in volts.

Abbreviation for voltage standing wave ratio.

A flammability rating established by Underwriters Laboratories for wires and cables that pass a specially designed vertical flame test, formerly designed FR-1.

Won top


Symbol for watt or wattage.

Wall Thickness
The thickness of an insulation or jacket.

Wide Area Network.

A unit of electrical power.

Wave Form
A graphical representation of a varying quantity. Usually, time is represented on the horizontal axis, and the current or voltage value is represented on the vertical axis.

The distance between positive peaks of a signal. As the frequency increases, and waves get closer together, the wavelength decreases.

Wireless Communications Service.

A conductor, either bare or insulated.

LEONI A.G. makes a broad variety of high performance cables needed to build the transmitting infrastructure required to support "wireless" devices.  Wireless is a technology that allows a device (phone, pager or satellite dish) to be unconnected from the transmission point of a voice, video or data signal.  The transmission infrastructure required to support such wireless devices is a wired platform of transmission towers and stations that communicate point to point and to telephone central offices.



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Symbol for reactance.

Crosslinked polyethylene is a thermoset and is crosslinked by radiation, thermally, or by moisture. XLPE offers a wide range of operating temperatures, excellent deformation, abrasion, and flame resistance. XLPE can be formulated with halogenated or non-halogenated flame retardant packages. Some grades are also rated XHHW-2 which offers excellent wet electrical properties.

A multi-pin audio Connector (typically 3 pins) used in microphone, line level and snake cable connections.

Expanded Polyethylene-Polyvinyl Chloride. Fire retardant.

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Symbol for impedance