Cable dictionary

Not sure what all terms in the cable industry means? Here we give you an explanation of the main terms used.


Abrasion resistance is the ability of a material (e.g. cable jacket) to resist surface wear.

A test that simulates long time environmental conditions in a relatively short time.

Audio frequency

Automatic gain control

By alternating (switching the polarity) of the current in a circuit, the distance over which power can be transmitted can be increased. However this can come at a cost as AC is more damaging to materials, and more dangerous to people than Direct Current (DC).

Amplitude modulation

conditions existing at a test or operating location prior to energizing equipment (e.g ambient temperature).

Also referred to as an Amp (SI-unit = A), an Ampere is a standard unit of current.

Defined as the amount of current that flows (for example through a wire) 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. Since the process generates heat the current rating of a cable is defined by the size of the conductor and the temperature rating of the surrounding insulation.

The maximum value of a varying wave form.

Representation of data by continually variable quantites.

Also referred to as Soft Drawn Wire.

Annealed Wire has been softened by heating to just below its melting point and then slowly cooled, this process generally lowers the tensile strength of a material, whilst improving both the flex-life and flexibility.

The decrease in magnitude of wave as it travels through any transmitting medium, such as a cable or circuitry. Attenuation is measured as a ratio or as the logarithm of a ratio (decibel).

A rating for a cable or other transmitting medium, which is the relative rate of voltage or current in the direction of travel. It is measured in decibels per unit of length of cable.

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.

That range of frequencies lying within the range of human hearing : approximately 20 to 20,000 Hz.

American Wire Gauge. A wire diameter specification. The smaller the AWG number, the larger the wire diameter.


A cable having two identical conductors with the same electromagnetic characteristics in relation to other conductors and to ground.

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.

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 logarithm10 of p1/p2);2logarithm10(e1/e2); and 2logarithm10(l1/l2). See dB.

A form of increased attenuation caused by (a) having an optical fiber curved around a restrictive radius ofcurvature or (b) microbends caused by minute distortions in the fiber impossed by externally induced perturbations.

Radius of curvature that a fiber optic metallic cable can bend without any adverse effects.

One billion electron volts.

A tape or thread used for holding assembled cable components in place.

One binary digit.

The method used to produce good electrical contact between metalic 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.

A group of textile or metallic filaments interwoven to form a tubular structure which may be applied over one or more wires, or flattened to form a strap. 

Á protective coating over an optical fiber.

Conductors twisted together with the same lay and direction without regard to geometric pattern.

Non-insulated tinned copper wire used as a common lead.

A synthetic rubber with good electrical insulating properties.

A group of adjacent binary digits (8 bits).


The method by which a group of insulated conductors is mechanically assembled or twisted together. 

The ability of a dielectric material between conductors to store electric charge when a difference of potential exists between the conductors. The unit of measurement is the farad, which is the capacitance value that will store a charge of one coulomb when a one-volt potencial difference exists between the conductors. In ac, one farad is the capacitance value which will permit one ampere of current when the voltage across the capacitor changes at a rate of one volt per second.

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 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.

community antenna television

citizens band.

closed-circuit television.

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

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

A term used to define cross sectional areas using an arithmetic short-cut in which the area of a round wire is taken as "diameter in mils (.001)"

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

A group of non-insulated wires twisted together and containing a center core with subsequent layers spirally wrapped around the core to form a single conductor. 

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

A material that offers little resistance to the flow of electrical current. 

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

The transfer of energy between two or more cables or components of a circuit. 

Central Processing Unit.

A type of interference caused by audio frequencies from one line being coupled into adjacent lines. The term is loosely used to also include coupling at higher frequencies.

cathode ray tube.

A two wire transmit/receive interface.

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.

Electrical current whose electrons flow in one direction only. It may be constant or pulsating as long as its movement is in the same direction. 

The ability of a material to withstand mechanical pressure without damage.



Direct current.

See resistance.

One-tenth of a bel. It 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. One decibel is the amount by which the pressure of a pure sine wave of sound must be varied in order for the change to be detected by the average human ear. The decibel can express an actual level only when comparing with some definate reference level that is assumed to be zero dB. 

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

An insulating (non-conducting) medium

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. 

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 as a dielectric. 

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.

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

Representation of data by discrete characters.

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

Any undesired change in a wave form or signal.

In a catv system, the transmission cable between the distribution amplifier and the drop cable.

An uninsulated wire in contact with a shield throughout its length. Used for terminating the shield.

In a catv system, the transmission cable from the distribution cable to a dwelling.


Voltage (electromotive force).

British terminology for zero-reference ground.

Electronic industries association (formerly RMA or RETMA) 

Any material that will return to its original dimensions after being stretched or distorted.

Referring to the combined electric and magnetic fields caused by electron motion through conductors. 

The transfer of energy by means of a varying magnetic field. Inductive coupling. 

A measure of the energy gained by an electron falling through an electric field produced by one volt. 

Pertaining to static electricity, or electricity at rest. An electric charge, for example.

The transfer of energy by means of a varying electrostatic field. Capacitive coupling.

Electromotive force (voltage).

The capability of doing work.

The capability of doing work.

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. 

Ethylene-propylene-diene monomer rubber. A material with good electrical insulating properties. 

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.

Electron volt.

See cellular polyethylene.

See cellular polyethylene.



A unit of capacity that will store one coulomb of electrical charge when one volt of electrical pressure is applied.

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 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.

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. 

A single, separate optical transmission element characterized by core and cladding. 

Light transmission through optical fibers for communication and signalling. 

An area through which electrical and/or magnetic lines of force pass.

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.

The ability of a cable to bend many times before breaking. 

The ability of a cable to bend in a short radius (also see limpness). 

Referring to circuit which has no connection to ground.

Frequency modulation.

See cellular polyethylene.

The number of times a periodic action occurs in a unit of time. The number of hertz that an electric current completes in 1 second. 

The characteristic of a device denoting the range of frequencies over which it may be used effectively. 

Normally, the 50 or 60 hertz power available in residential areas.


The increase of voltage, current, or power over which it may be used effectively.

Cable used in exploring for underground oil deposits. 

A unit of frequency equal to one billion hertz.

A short length of wire which is soldered onto a circuit component and used as a small adjustable capacitor. A gimmick is often two short insulated wires that are twisted together to a form of a capacitor.


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.

An electrical connection to the earth, generally through a ground rod. Also a common return to a point of zero potential, such as the metal chassis in radio equipment.

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.

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.


Symbol designation for magnetic intensity and henry 

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). 

The unit of frequency, one cycle per second.

High frequency.

The band from 3 to 30 MHZ in the radio spectrum, as designated by the federal communications.

A term used to describe the 60- or 120-hps sounds present in the sound of some communications equipment. Usually hum is the result of undesired coupling to a 60-hps source or to the defective filtering of 120-hps 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.


Symbol used to designate current.

Symbol for inductance.

Formula for power in watts, where i=current in amperes, r=resistance in ohms. also see watt. 


The total opposition a circuit, cable, or component offers to alternating current flow. It includes both resistance and reactance and is generally expressed in ohms and designated by the symbol z.

a condition where by the impedance of particular circuit cable or components is the same as the impedance of the circuit, cable or device to which it is connected. 

A transformer designed to match the impedance of one circuit to that of another.

In a transmission cable of infinite length, the ratio of the applied voltage to the resultant current at the 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.

Generally, the area of 25,000 ohms or higher.

Generally, the area of 1 through 600 ohms.

A section of transmission line or pair of conductors cut to match the impedance of a load. Also called matching sub. 

a property of a conductor or circuit which resists a change in a current. It causes current changes to lag behind voltage changes and is measured in henrys.

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. 

Heating a conducting material by placing it in a rapidly changing magnetic field. The changing field induces electric currents in the material and I2R losses account for the resultant heat. 

Sometimes called the semiconductor diode. A laser in which the lasing occurs at the junction of n-type and p-type semiconductor material.

A signal (or power) which is applied to a piece of electric appartus or the terminals on the apparatus to which a signal or power is applied. 

A measure of the attenuation of a device by determining the output of a system before and after the device is inserted into the system.

A material having good dielectric properties which is used to separate close electrical components, such as cable conductors and circuit components. 

The molecule separation pressure caused by a potential difference across an insulator. The practical stress on insulation is expressed in volts per mil. 

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. 

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.

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.

The potential at which a material ionizes. The potential at which an atom gives up an electron.

Insulated power cable engineers association.

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

Ignition radiation suppression.

The ability of a circuit or component to reject interference, usually expressed in dB. 


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


1000 electron volts.

Prefix meaning thousand.

Tensile strength in thousands of pounds per square inch. 

Kilovolt (1000 volts)

Kilovolt ampere.



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

Pertaining to wire and cable, the axial distance required for one cabled conductor or conductor strand to complete one revolution about the axis around which it is cabled. 

The twist in the cable as indicated by the top strands while looking along the axis of the cable away from the observer. Described as "right hand" (z)or "left hand" (s). 

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.

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

Low frequency.

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 cable to lay flat or conform to a surface as with microphone cables (also see flexibility). 

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. 

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

The amplitude of the signal at a certain point on a transmission line. Usually expressed in decibels. 

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


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


The mission of the NFPA is to reduce the burden of fire on the quality of life by advocating scientifically-based consensus codes and standards, research, and education for fire and related safety issues. The NFPA revises the National Electrical Code (NEC) every 3 years. The NEC defines classifications of cable as per UL tests.

National Fire Protection Association


Underwriters Laboratories Inc