|
| Term |
Definition |
5-Mil Copper
|
Solid Copper Shield. Provides added electrical
protection. |
802.14
|
IEEE's Cable TV MAC and PHY Protocol Working
Group. |
A
|
Ampere |
ABR
|
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. |
AC
|
Alternating current. Electric current that
alternates or reverses polarity in a cyclical manner (e.g. 60 Hertz AC
power) |
Accelerated Aging
|
A test that simulates long time environmental
conditions in a relatively short time. |
ACR
|
Attenuation Crosstalk Ratio. The difference
between attenuation and crosstalk, measured in dB, at a given frequency.
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. |
ADSL
|
Asymmetric Digital Subscriber Line |
AES/EBU
|
Informal name of a digital audio standard
established jointly by the AES (Audio Engineering Society) and EBU
(European Broadcast Union) organizations. |
AF
|
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 in a hollow plastic tube
allowing the remainder of the dielectric to be air. Typical velocities of
up to 84% can be achieved in this design. |
Alloy
|
A combination of two or more different
polymers/metals. Usually combined to make use of different properties of
each polymer/ metal. |
Alpeth
|
Coated Aluminum Polyethylene. Basic sheath. |
Alternating Current (AC)
|
Electric current that alternates or reverses
polarity in a cyclical manner (e.g. 60 Hertz AC power) |
AM
|
Amplitude modulation. |
Ambient
|
Conditions that exist in the environment of
the cable. 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. |
Ampacity
|
Current handling capability expressed in
amperes. The maximum current a conductor can carry without being heated
beyond a safe limit. |
Ampere
|
A standard unit of current. Defined as the
amount of current that flows when one volt of electromotive force (EMF) is
applied across one ohm of resistance. One ampere of current is produced by
one coulomb of charge passing a point in one second. |
Amplitude
|
The magnitude of a current or voltage. It can
be the maximum, minimum, average, or RMS value of an alternating current
(AC) signal. These four magnitudes are the same for a direct current (DC)
signal. |
Analog
|
Representation of data by continuously
variable quantities as opposed to a finite number of discrete quantities
in digital. |
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. |
Anneal
|
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. |
ANSI
|
American National Standards Institute. |
ASP
|
Aluminum Steel Polyethylene. Provides
mechanical and electrical protection. |
ASTM
|
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. |
ATM
|
Asynchronous Transfer Mode. |
Attenuation
|
The decrease in magnitude of a signal as it
travels through any transmitting medium, such as a cable or circuitry.
Attenuation is usually expressed logarithmically as the ratio of the
original and decreased signal amplitudes. It is usually expressed in
decibels (dB). |
Audio
|
A term used to describe sounds within the
range of human hearing (20 Hz to 20 kHz). Also used to describe devices
which are designed to operate within this range. |
Audio Frequency
|
Frequencies within the range of human hearing
(approximately 20 Hz to 20 kHz). |
AWG
|
American Wire Gage. A wire diameter
specification. The smaller the AWG number, the larger the wire diameter. |
AWM
|
Appliance Wiring Material. A UL designation
for a type of wire. |
Backbone
|
The cable used to connect all systems of a
multi-level distributed system to an intermediate system. |
Backshell
|
Housing on a connector that covers the area
where the cable conductors connect to the connector contacts. It can be a
metal housing providing continuity of the shield through IDC connectors. |
Balanced Line
|
A cable having two identical conductors which
carry voltages opposite in polarity, but equal in magnitude with respect
to ground, suitable for differential signal transmission. |
Balun
|
Balanced to unbalanced (Bal-un) transformer
used to connect an unbalanced transmission line (i.e. coaxial cable) to a
balanced system or cable, or vice versa. It can also provide impedance
transformation, as 300 ohm balanced to 75 ohm unbalanced. |
Bandwidth
|
The difference between the upper and lower
limits of a given band of frequencies. It is 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. |
Baud
|
Rate of digital transmission equal to the
reciprocal of the time of one output signaling element. |
Bel
|
A unit that represents the logarithm of the
ratio of two levels. One bel equals the base 10 logarithm of the ratio of
two power levels. It is also equal to the base 10 logarithm of square of
the ratio of two voltage or current levels, provided the impedances are
the same at the two levels. See dB. |
Belden
|
A leading manufacturer of the specialty wire,
cable and fiber products needed for new applications in data, audio, video
and voice signal transmission, among other things. |
Beldfoil
|
Belden trademark for highly effective
electrostatic shield of reinforced metallic foil. |
Beldsol
|
Solderable Belden magnet wire combining
insulating films of polyurethane for excellent dielectric characteristics
and nylon for mechanical protection. |
BelflexR
|
A premium hybrid matte-finish jacket material
that exhibits superior flexibility at low temperatures along with
excellent abrasion resistance compared to standard PVC jacketing
materials. |
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. |
Binder
|
A tape or thread used for holding assembled
cable components in place. |
Bit
|
One binary digit. |
Bit Error Rate
|
The number of errors occurring in a system per
unit of time (e.g. bits per second) |
Bits Per Second
|
The number of binary bits that can be
transmitted per second (bps) - i.e. Mbps (Mega = million), Gbps (Giga =
billion). |
BNC
|
Abbreviation for "Bayonet Neil Concelman". A
coaxial cable connector used extensively in video and R. F. applications
and named for its inventors. |
Bonded
|
1. Adhesive application of a metallic
shielding tape to the dielectric of a coaxial cable to improved electrical
performance and ease of connector installation. Also refers to adhesive
application of a metallic shielding taper to the jacket of a cable. 2.
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. |
Bonded ASP
|
Aluminum Steel Polyethylene where the steel is
bonded to polyethylene for strength. Filled cables for use in ducts. |
Bonding
|
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. |
Booster
|
An amplifier inserted into a cable to increase
the signal amplitude in order to compensate for signal loss due to
attenuation. This extends the transmission range of the cable.
Transformers may be employed to boost ac voltages. The term booster is
also applied to amplifiers used in television receiving antenna systems. |
BPS
|
Bits per second (see). |
BPSK
|
Binary Phase Sift Keying. A type of digital
transmission where two phases of the signal are possible to represent
binary one and zero. |
Braid
|
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. |
Braid Angle
|
The angle between a strand of wire in a braid
shield and the longitudinal axis (i.e.axis along the length of the center)
of the cable it is wound around. |
Breakdown Voltage
|
The voltage at which the insulation between
two conductors will fail and allow electricity to conduct or 'arc'. |
Breakout
|
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. |
BRI
|
Basic Rate Interface ISDN. |
Broadband
|
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. |
Buffer
|
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. |
Buried
|
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. |
Byte
|
A group of eight adjacent binary digits (8
bits). |
C
|
Capacitance (electrical). Celsius
(temperature). |
Cable
|
A group of individually insulated conductors
or subcomponents twisted helically. |
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. |
Cabling
|
The grouping or twisting together of two or
more insulated conductors or subcomponents to form a cable. |
CACSP
|
Coated Aluminum, Coated Steel, Polyethylene.
Provides additional strength and protection. |
Canadian Electrical Code (CEC)
|
Canadian version of the US National Electrical
Code (NEC). |
CAP
|
Carrierless Amplitude Phase Modulation. |
Capacitance
|
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/(2*pi*f*C) where pi is approximately 3.1416, f is the
frequency in Hz, and C is the capacitance in farads. |
Capacitor
|
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. |
CASPIC
|
Coated Aluminum, Coated Steel. |
Category
|
Rating of a local area network (LAN) cable
established by TIA/EIA to indicate the level of electrical performance. |
Category Cables
|
Belden manufactures Category 3 to 7 cables,
all high performance twisted pair data cables. The higher the category
number, the greater the bandwidth. Category 7 is currently the highest
performance telecommunication wire available. Ours is certified to
applicable UL standards. |
CATV
|
Abbreviation for Community Antenna
Television. Cable TV. |
CB
|
Citizens band. |
CBR
|
Constant Bit Rate. |
CCTV
|
Closed-circuit television. |
Cellular Polyethylene
|
Expanded or "foam" polyethylene, consists of
individual closed cells of inert gas suspended in a polyethylene medium.
The result is a desirable reduction of the dielectric constant compared to
solid polyethylene, which decreases attenuation and increases the velocity
of propagation. |
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. |
Channel
|
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 video signal that contains
the color information. |
Circuit
|
A system of conducting media designed to pass
an electric current. |
Circular Mil
|
Area of a wire that is one-thousandth of an
inch (.001 inch, one mil) in diameter. This area is pi/4 of a square mil.
The circular mil area (CMA, cmil) equals the diameter in mils squared. By
knowing the CMA of various conductors, they can be used to determine what
conductivity and gage size various combinations will produce. |
Cladding
|
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 or a layer of
metal applied over another. Cladding is often chosen to improve
conductivity or to resist corrosion. |
CO
|
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. Used by
cable TV companies to distribute signals to homes and businesses. Also
used by telephone companies in some applications and by cellular
telephone, radio, and television installations. |
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. |
COLS
|
Commercial Online Service. |
Component Video
|
The unencoded output of a camera, video tape
recorder, etc., whereby each red, green, and blue video signal is
transmitted down a separate cable (usually coax) to improve picture
quality. Can also refer to a video system where the luminance and
chrominance video components are kept separate. |
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, and blue video signals are
combined with the synchronizing, blanking, and color burst signals and 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. |
Conductivity
|
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 and is measured in siemens (S) or mhos. |
Conductor
|
A substance, usually metal, used to transfer
electrical energy from point to point. |
Conduit
|
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, to contain the fire of a burning wire or cable. |
Connector
|
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. |
Copperweld
|
Trademark of Copperweld Steel Co. for
copper-clad steel conductor. |
Cord
|
A very flexible insulated cable. |
Core
|
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. |
Corona
|
The ionization of gasses about a conductor
that results when the potential gradient reaches a certain value. |
Coupling
|
The transfer of energy (without direct
electrical contact) between two or more cables or components of a circuit. |
Coverage
|
How well a metal shield covers the underlying
surface. Measured in percent. |
CPE
|
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. |
CPS
|
Abbreviation for cycles per second. This term
has been replace by hertz is common usage. |
CPU
|
Central Processing Unit. |
Crosstalk
|
A type of interference caused by signals from
one pair or cable being coupled into adjacent pairs or cables. Can occur
with audio, data, or RF signals. |
CRT
|
Cathode Ray Tube. |
CSA
|
Abbreviation for Canadian Standards
Association, the Canadian version of the Underwriters Laboratories. |
CSMA/D
|
Carrier Sense Multiple Access/Collision
Detection. |
CSR
|
Customer Service Representative. |
CUPIC
|
Copper. |
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)
|
Electric current that alternates or reverses
polarity in a cyclical manner (e.g. 60 Hertz AC power). |
Current, Direct (dc)
|
Electrical current whose electrons flow in one
direction only and is generally constant. |
Cut-through Resistance
|
A test to determine the ability of a material
to withstand the application of blades or sharp edges without being cut. |
D1
|
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). |
D2
|
A composite digital video recording format.
Records on 19 mm magnetic tape. |
D3
|
A composite digital video recording format.
Records on 1/2 inch (12.7 mm) magnetic tape. |
Daisy Chain
|
A cable assembly with three or more
termination areas. |
Datalene
|
Belden trademark for foam polyolefin. |
DAVIC
|
Digital Audio Video Council. |
dB
|
Decibel. |
DBS
|
Direct Broadcast Satellite. |
DC
|
Direct current. |
DC Resistance
|
See resistance. |
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. |
DEPIC
|
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, such as
higher temperature, or where multiple conductors are together in one
conduit. |
DES
|
Data Encryption Standard. |
DHCP
|
Dynamic Host Configuration Protocol. |
Dielectric
|
An insulating (non-conducting) medium. It is
the insulating material between conductors carrying a signal in a cable.
In coaxial cables it is between the center conductor and the outer
conductor. In twisted pair cables it is the insulation between conductors
plus any surrounding air or other material. |
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 relative 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 an insulation can withstand before
it breaks down. Usually expressed as "volts per mil". |
Digital Signal
|
An electrical signal which possesses two
distinct states (on/off, positive/negative). |
Dispersion
|
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. |
Distortion
|
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. |
DMT
|
Discrete Multitone. |
DOCSIS
|
Data Over Cable Service Interface
Specification (trade mark). Defines interface requirements for cable
modems involved in high-speed data distribution over cable television
system networks. |
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. |
DSL
|
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. |
Duobond II
|
Belden trademark for a laminated shielding
tape consisting of heat sensitive adhesive, aluminum foil, polyester or
polypropylene, and aluminum foil. |
Duofoil
|
Belden trademark for a shield in which
metallic foil is applied to both sides of a supporting plastic film. |
DVB
|
Digital Video Broadcasting. |
E
|
Voltage (electromotive force). |
Earth
|
British terminology for zero-reference ground. |
Edge Margin
|
Margin. |
EFP
|
Electronic Field Production. Video production
for commercials, television shows and other non-news purposes done outside
the studio. |
EIA
|
Electronic Industries Association (formerly
RMA or RETMA). |
Elastomer
|
Any material that will return to its original
dimensions after being stretched or distorted. |
Electromagnetic
|
Referring to the combined electric and
magnetic fields caused by electron motion through conductors. |
Electromagnetic Coupling
|
The transfer of energy by means of a varying
magnetic field. Inductive coupling. |
Electron Volt
|
A measure of the energy gained by an electron
passing through an electric field produced by one volt. |
Electrostatic
|
Pertaining to static electricity, or
electricity at rest. An electric charge, for example. |
Electrostatic Coupling
|
The transfer of energy by means of a varying
electrostatic field. Capacitive coupling. |
ELFEXT
|
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". |
Elongation
|
The increase in length of a wire or cable
cause by longitudinal tension. |
EMF
|
Electromotive force (voltage). |
EMI
|
Electromagnetic Interference. |
Energy
|
The capability of doing work. |
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. |
ENG
|
Electronic News Gathering. |
EPDM
|
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. |
EPR
|
Ethylene-propylene copolymer rubber. A
material with good electrical insulating properties. |
Equilay
|
More than one layer of helically laid wires
with the length of the lay the same for each layer. |
ETP
|
Abbreviation for a copper refining process
called Electrolytic Tough Pitch. This process produces a conductor that is
99.95% pure copper (per ASTM B115) resulting in high conductivity. |
eV
|
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. |
f
|
Frequency. |
Farad
|
A unit of capacity that will store one coulomb
of electrical charge when one volt of electrical pressure is applied. |
FAS
|
Fire Alarm and Signal Cable, CSA (Canadian
Standards Association) Cable Designation. |
FAQ
|
Frequently Asked Question. |
FCFC
|
Abbreviation for flat conductor flat cable. |
FDDI
|
Fiber Distributed Data Interface. |
FEC
|
Forward Error Correction. |
Feedback
|
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. |
FEP
|
Fluorinated ethylene-propylene. A
thermo-plastic material with good electrical insulating properties and
chemical and heat resistance. |
Ferrous
|
Composed of and/or containing iron. A ferrous
metal exhibits magnetic characteristics. |
FEXT
|
Far End Crosstalk. Crosstalk induced on the
pairs, measured at the "far" end of the cable, referenced to the near end
input signal. Usually expressed in decibels. |
Fiber
|
A single, separate optical transmission
element characterized by core and cladding. |
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. |
Field
|
An area through which electric and/or magnetic
lines of force pass. |
Filled
|
Cables that are gel filled. |
Fillers
|
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. |
Flamarrest
|
Belden trademark for a plenum grade
chloride-based thermoplastic jacketing material with low smoke and low
flame spread properties; more flexible than traditional fluorocopolymer
jacket materials. Cables jacketed with Flamarrest meet the UL Standard
910, Plenum Cable Flame Test. |
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
|
A conductor with a width-to-thickness ratio of
arbitrarily 5 to 1 or greater. |
Flat Conductor Cable
|
A flat cable with a plurality of flat
conductors. |
Flex Life
|
The qualification of the number of times a
cable may bend before breaking. |
Flexibility
|
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. |
Floating
|
Referring to a circuit which has no connection
to ground. |
Fluorocopolymer
|
Generic term for PVDF. |
FM
|
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. |
FR-TPE
|
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. |
FREP
|
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
characteristics, deformation resistance, and also meets the flame
retardant needs of industrial control cables. |
Frequency
|
The number of times a periodic action occurs
in one second. Measured in Hertz. |
Frequency Response
|
The amplitude versus frequency characteristics
of a device. Also may refer to the range of frequencies over which the
device operates within prescribed performance |
Frequency, Power
|
Normally, the 50 or 60 hertz power used to
operate most AC powered equipment. The frequency of AC power supplied by
electric utilities companies. |
FSK
|
Frequency Shift Keying. |
FTTC
|
Fiber-to-the-Curb. |
Gage
|
The physical diameter of a wire. A standard
for expressing wire diameter. As the AWG number gets smaller, the wire
diameter gets larger. |
Gain
|
The increase of voltage, current, or power
over a standard or previous reading. Usually expressed in decibels. |
Geosol
|
A solderable, extra tough film insulation
developed b Belden for use in geophysical cables and miniature cables. |
Giga
|
One billion. |
Gigahertz (GHz)
|
A unit of frequency equal to one billion
hertz. |
GND
|
Ground. |
Gopher
|
Gopher Resistant Copper Alloy. Provides
shield and added protection in a single layer. |
GOPIC
|
Gopher. |
Graded-Index
|
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
|
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. |
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. |
H
|
Symbolic designation for magnetic field
intensity. Abbreviation for henrys (unit of inductance). |
Halar
|
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. |
Harness
|
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. |
HDSL
|
High bit-rate Digital Subscriber Line. |
Headroom
|
The amount by which a cable ACR exceeds the
specified requirements. The TIA/EIA 568B standard specifies a minimum of
10 dB of ACR for Category 5e certification at 100 MHz. |
Henry
|
Unit of inductance (H) that will produce a
voltage drop of one volt when the current changes at the rate of one
ampere per second. |
Hertz (Hz)
|
Unit of frequency equal to one cycle per
second. |
Heterogeneous Insulation
|
A cable insulating system composed of two or
more layers of different insulating materials. |
HF
|
High Frequency. International
Telecommunication Union designation for the 3-30 MHz band of frequencies. |
HFC
|
Hybrid Fiber/Coaxial. |
High Frequency
|
International Telecommunication Union
designation for the 3-30 MHz band of frequencies. |
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 between the workstation outlet and
the telecommunications closet. Limited to 90 meters maximum per TIA/EIA
568B.1. |
HSCDS
|
High-Speed Cable Data Service. |
HTML
|
Hypertext Markup Language. |
HTTP
|
Hypertext Transfer Protocol. |
Hum
|
Term used to describe noise in a audio, video,
or other system that comes from 60 Hz power or its harmonic(s). So named
for the low-frequency humming sound produced in audio systems. Usually hum
is the result of undesired coupling from a 60 Hz source or of inadequate
filtering of the DC output of an AC input power supply. |
Hypalon
|
A DuPont trade name for a synthetic rubber (chlorosulfonated
polyethylene) used as insulating and jacketing material for wire and
cable. |
I
|
Symbol used to designate current. |
I/O Interconnection
|
Input/Output interface to the "outside world." |
I2R
|
Formula for power in watts, where I=current in
amperes, R=resistance in ohms. |
ICEA
|
Insulated Cable Engineers Association. |
IDC
|
Insulation Displacement Connector. Type of
connector where contact is made to the cable conductor(s) by cutting
through the individual conductor's insulation. The conductor does not need
to have its insulation removed prior to connection. Flat cable often uses
IDCs to simultaneous connect all conductors. |
IDSL
|
ISDN Digital Subscriber Line. |
IEEE
|
Institute of Electrical and Electronic
Engineers. |
IETF
|
Internet Engineering Task Force. |
IF
|
Intermediate Frequency. |
IFB
|
Interrupted Feedback (Foldback). Interruptible
Feedback (Foldback). A monitoring scheme often used in television where
the feed of program audio to an on-air person can be interrupted with
directions, cues, or other information. Usually integrated into the
intercom system. |
IGMP
|
Internet Group Management Protocol. |
Impedance
|
The total opposition that a circuit offers to
the flow of alternating current or any other varying current at a
particular frequency. |
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. |
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. |
Inductance
|
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
|
The phenomenon of a voltage, magnetic field,
or electrostatic charge being produced in an object from the source of
such fields. |
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 losses account for the resultant heat. |
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. |
INMS
|
Integrated Network Management System. |
Input
|
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 and/or
component(s) by determining the output of a system before and after the
device is inserted into the system. |
Insulation
|
A material having good dielectric properties
which is used to separate close electrical components, such as cable
conductors and circuit components. |
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. |
Interface
|
The region where two systems or a major and a
minor system meet and interact with each other. |
Interference
|
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
|
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. |
Ionization Voltage
|
The potential at which a material ionizes. The
potential at which an atom gives up an electron. |
IP
|
Internet Protocol. |
IPCDN
|
IP Over Cable Data Network working group of
the IETF. |
IR
|
Insulation Resistance. |
IR Drop
|
The designation of a voltage drop in terms of
current and resistance. See also Voltage Drop. |
IRC
|
Inter Relay Chat. |
IRS
|
Ignition radiation suppression. |
ISDN
|
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. |
ISO
|
International Standards Organization. |
Isolation
|
The ability of a circuit or component to
reject interference, usually expressed in dB. |
ISP
|
Internet Service Provider. |
ITFS
|
Instructional Television Fixed Service. |
ITU
|
International Telecommunications Union. |
Jacket
|
Pertaining to wire and cable, the outer
protective covering that may also provide additional insulation. |
Jumper
|
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. |
kB
|
Kilobyte. |
keV
|
1000 electron volts. |
Kilo
|
One thousand. |
KPSI
|
Tensile strength in thousands of pounds per
square inch. |
kV
|
Kilovolt (1000 volts). |
kVA
|
Kilo Volt-ampere. One thousand volt-amperes
(VA). See also VA. |
kW
|
Kilowatt. |
L
|
Symbol for inductance. |
Laminated Cable
|
Insulated or uninsulated wires which are
encapsulated by two sheets of laminate material to maintain a
predetermined pitch. |
LAN
|
Local Area Network. A data network connecting
any number of users, intended to serve a small area. 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. |
Laser
|
A coherent source of light with a narrow beam
and a narrow spectral bandwidth (about 2nm). |
Lay
|
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. |
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". |
Lead Dress
|
The placement or routing of wiring and
component leads in an electrical circuit. |
Lead-in
|
The cable that provides the path for r-f
energy between the antenna and the receiver or transmitter. |
Leakage
|
The undesirable passage of current over the
surface of or through an insulator. |
LEC
|
Local Exchange Carrier. |
Level
|
A measure of the difference between a quantity
or value and an established reference. |
LF
|
Low frequency. International
Telecommunication Union designation for the 30-300 kHz band of
frequencies. |
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. |
Limpness
|
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. See also Voltage Drop and
IR Drop. |
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.. 0 dBV). |
Line Voltage
|
The value of the potential existing on a
supply or power line. |
LMDS
|
Local Multipoint Distribution Service |
Load
|
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. |
Loading
|
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. See also LAN. |
Long-wire Antenna
|
An antenna conductor length in excess of
one-half of a wavelength. |
Loss
|
Energy or signal lost without accomplishing
useful work. |
Lossy
|
Having high losses resulting in efficiency. |
Low Frequency
|
International Telecommunication Union
designation for the 30-300 kHz band of frequencies. |
Luminance Signal
|
The portion of the composite video signal that
represents the brightness or the black and white information. |
m
|
Prefix for milli or one-thousandth. |
M
|
Mutual inductance. The abbreviation for mega
or 1 million. And also indicates 1000 (one thousand) feet in the wire
industry. Lower case m is for milli or one-thousandth. See also m. |
M'
|
Notation representing 1000 feet. |
mA
|
milliampere (one-thousandth of an ampere). |
MAC
|
Media Access Control (layer of OSI Reference
Model). |
MAN
|
Metropolitan Area Network. 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. |
MAP
|
Manufacturing Automation Protocol. A
manufacturing automation protocol based on IEEE 802.4 standards. |
Margin
|
Distance between reference edge of cable and
nearest edge of first conductor or center of first conductor. |
Mass-Termination
|
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. |
MATV
|
Abbreviation for Master Antenna Television. |
MB
|
Megabyte. |
Mbps
|
Mega bits per second - the number of bits, in
millions, transmitted per second. |
MCNS
|
Multimedia Cable Network System Partners Ltd. |
MDS
|
Multipoint Distribution System. |
Mega
|
Prefix meaning million. |
Megahertz (MHz)
|
Unit of frequency equal to one million hertz. |
Metropolitan Area Network
|
A data network intended to serve the area of a
city or an area of similar size. See also MAN. |
mfd
|
Microfarad (one-millionth of a farad). Modern
abbreviation is uF (lower case Green mu followed by F). |
Mho
|
The unit of conductance equal to the
reciprocal of the unit of resistance (ohm). |
MHz
|
Megahertz (see also). |
Micro
|
Prefix meaning one-millionth. |
Microfarad
|
One-millionth of a farad (uf, ufd, mf, and mfd
are common abbreviations). |
Micromicrofarad
|
One-millionth of a microfarad (uuf, uufd, mmf,
mmfd are common abbreviations). Modern usage is picofarad (pF). |
Micron
|
Millionth of a meter. |
Microphonics
|
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. |
Mil
|
A unit of length equal to one thousandth of an
inch (.001"). |
Milli
|
Prefix meaning one-thousandth. |
MMDS
|
Multichannel Multipoint Distribution System. |
Mode
|
A single electromagnetic wave traveling in an
optical fiber. |
Modem
|
Modulator-Demodulator. Device that converts
signals in one form to another form compatible with another kind of
equipment. |
Modulation
|
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. |
MSO
|
Multiple System Operator. Cable TV term
referring to companies that operator multiple cable TV systems in numerous
cities. |
MTP
|
Simple Mail Transfer Protocol. |
Multi-Conductor Cable
|
Cable with more than one conductor. |
Multiplex
|
A technique for putting two or more signals
into a single channel. |
Mutual Capacitance
|
Effective capacitance between two conductors
when the effects of the other conductors and shield, if present, are
removed. |
mV
|
Millivolt (one-thousandth of a volt). |
mW
|
Milliwatt (one-thousandth of a watt). |
Mylar
|
DuPont trademark for polyethylene terephtalate
(polyester) film. |
N
|
Type of coaxial connector named after its
inventor, Paul Neil of Bell Labs. |
Nano
|
One-billionth. |
Nanometer (nm)
|
One billionth of a meter. |
Nanosecond
|
One billionth of a second. |
NAP
|
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. |
NBR
|
Butadiene-acrylonitrile copolymer rubber, a
material with good oil and chemical resistance. |
NEC
|
National Electrical Code. A publication of the
National Fire Protection Association (NFPA) which outlines requirements
for electrical wiring and building construction. |
NEMA
|
National Electrical Manufacturers Association. |
Neoprene
|
A synthetic rubber with good resistance to
oil, chemical, and flame. Also called polychloroprene. |
Network
|
A network is a method of data communications
between computers. |
NEXT
|
Near-end Crosstalk. Crosstalk induced on the
pairs, measured at the end "near" the transmitter. Usually expressed in
decibels. |
NFPA
|
National Fire Protection Association. |
Nibble
|
One half byte (4 bits). |
NOC
|
Network Operations Center. |
Noise
|
In a cable or circuit, any extraneous signal
which tends to interfere with the signal normally present in or passing
through the system. |
Nomex
|
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. |
Non-Plenum
|
A description for a cable that does not meet
the requirements of UL 910 CMP flame test. Such a cable cannot be
installed in an area that is used for air return (plenum). |
Notch
|
The removal of the web section between
conductors of a flat cable to aid in stripping, slitting, and termination. |
NTSC
|
National Television System Committee.
Organization that formulated standards for the current U.S. color
television system. This system is used in most countries of the Americas
and in other parts of the world. It was designed to be compatible with the
existing monochrome TV sets, so that they would not become obsolete. Color
televisions would also be able to receive monochrome transmissions. NTSC
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,
29.97 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. |
Nylon
|
An abrasion-resistant thermoplastic with good
chemical resistance. |
OFDM
|
Orthogonal Frequency Division Multiplexing. |
OFHC
|
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. |
Ohm
|
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. |
OSI
|
Open System Interconnect (Model for networking
protocols). |
OSS
|
Operations Support Systems. |
Output
|
The useful power or signal delivered by a
circuit or device. |
Ozone
|
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). |
Paired Cable
|
Cable with conductors cabled in groups of two. |
PAL
|
Phase Alternation 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. The digits are sent on separate conductors rather than
sequentially on one transmission line (serial). Often used informally to
refer to parallel digital television signals. |
PASP
|
Polyethylene Aluminum Steel Polyethylene.
provides additional lightning and gopher protection. |
Patchcord
|
A flexible piece of cable terminated at both
ends with plugs. Used for interconnecting circuits on a patchboard, in a
wiring closet, or at the work area. |
PC
|
Personal Computer. |
PE
|
Polyethylene. |
Peak
|
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. |
Periodicity
|
The uniformly spaced cable impedance
variations that result in addition of the reflections of a signal. The
distance between them is the half wavelength most affected. Multiples of
that frequency are also affected. Even very slight variations, which
appear over and over in a construction or installation, can have major
effects on signal integrity because of periodicity. |
Permanent Link
|
The horizontal cable including the workstation
outlet and patch panel in the telecommunications closet plus two meters of
cable at each end for testing. Limited to a maximum of 90 meters in TIA/EIA
568B.1. |
Phase
|
An angular relationship between waves. |
Phase Shift
|
A change in the phase relationship between two
alternating quantities. |
Photodetector (Receiver)
|
Converts 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. |
PHY
|
Physical (layer of OSI Reference Model). See
also Physical Layer. |
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. |
PIC
|
Plastic Insulated Conductor. Provides strong
insulation. |
Pickup
|
Any device which is capable of transforming a
measurable quantity of intelligence (such as sound) into relative
electrical signals (e.g., a microphone). |
Pico
|
One-trillionth. |
Picofarad
|
One trillionth of a farad. A micromicrofarad.
Abbreviated pF in modern usage or mmF in earlier usage. |
Pin-diode
|
A photodetector used to convert optical
signals to electrical signals in a receiver. See also Photodetector. |
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. 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. |
Plastic
|
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. |
Plasticizer
|
A chemical added to plastics to make them
softer and more flexible. |
Plenum
|
A compartment or chamber to which one or more
air ducts are connected and that forms part of the air distribution
system. A description for a cable that passes the UL 910 CMP flame test
requirements. |
Plug
|
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. |
Polarization
|
The orientation of a flat cable or a
rectangular connector. e.g., for gray flat cable, the colored edge
indicating the number one conductor. |
Polybutadiene
|
A type of synthetic rubber often blended with
other synthetic rubbers to improve their properties. |
Polyethylene
|
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. |
Polymer
|
A substance made of many repeating chemical
units or molecules. The term polymer is often used in place of plastic,
rubber, or elastomer. |
Polyolefin
|
Any of the polymers and copolymers of the
ethylene family of hydrocarbons, such as polyethylene and polypropylene. |
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. |
POTS
|
Plain Old Telephone Service. 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. |
Potting
|
Sealing by filling with a substance to exclude
moisture. |
Power
|
The amount of work per unit of time. Usually
expressed in watts. Power equals the product of voltage and current
(P=V*I). |
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. |
PP
|
Polypropylene. |
PPP
|
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. |
PRI
|
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 after each bit. |
PSTN
|
Public Switched Telephone Network. |
Pulse
|
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. |
Putup
|
Packaging of finished wire or cable. |
PVC
|
Polyvinyl chloride (see also). |
PVDF
|
Polyvinylidene Fluoride. |
QAM
|
Quandrature Amplitude Modulation. |
QOS
|
Quality of Service. |
QPSK
|
Quaternary Phase Shift Keying or Quadrature
PSK. |
Quad
|
A four conductor cable. Also called "star
quad". |
R
|
Symbol for resistance. |
R-F
|
Radio-frequency. |
Radio Frequency (RF)
|
Radio Frequency. Includes frequencies from a
few kilohertz to several hundred gigahertz. Used to transmit information
from point to point over the airwaves or down coaxial cable. |
RAM
|
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. |
RDC
|
Regional Data Center. |
Reactance
|
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. |
Receiver
|
An electronic package that converts light
energy to electrical energy in a fiber optic system. Also refers to a unit
that converts an RF signal to another type of signal (e.g. radio,
television). See also Photodetector. |
Receptacle
|
A female housing with male or female contacts. |
Reference Edge
|
Edge of cable or conductor from which
measurements are made, such as in flat cable. 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
|
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. |
Reflection Loss
|
The part of a signal which is lost due to
reflection of power at a line discontinuity. |
Refractive Index
|
The ratio of light velocity in a vacuum to its
velocity in the transmitting medium. |
Registration
|
Alignment of one object with relation to
another. In flat cables it involves aligning conductors with contacts or
solder pads. Also called register. |
Repeater
|
A receiver and transmitter combination used to
regenerate an attenuated signal. |
Resistance
|
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. |
Resonance
|
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. |
Return Loss
|
Measure of signal reflections from a cable or
device with a fixed, standard reference impedance on the measuring
equipment. Expressed in decibels. |
RF
|
Radio Frequency. |
RFI
|
Radio Frequency Interference. |
RFP
|
Request for Proposals. |
RG/U
|
RG is the abbreviation for radio guide, a
military designation for a coaxial cable, and U stands for universal. |
RGB
|
Abbreviation for the three parts of color
video signal: red, green and blue. 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. |
RJ-45
|
Modular telecommunications connector. |
RL
|
Return Loss. |
RMS
|
Root-mean-square. |
Rope Strand
|
A conductor composed of groups of twisted
strands. |
Round Conductor Flat Cable (RCFC)
|
A cable made with parallel round conductors in
the same plane. |
Routing
|
The path followed by a cable or conductor. |
RSVP
|
Resource Reservation Protocol. |
RTP
|
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. |
RUS 1755.900 (aka PE90)
|
A specification for fiber optic cables
currently in high demand by the telecommunications industry. Only a
handful of U.S. manufacturers can produce fiber optic cables to this
specification. Belden is one of them. |
S-CDMA
|
Synchronous Code Division Multiple Access. |
S-HDSL
|
Single-pair High bit-rate Digital Subscriber
Line. |
SAE
|
Society of Automotive Engineers. |
SBR
|
A copolymer of styrene and butadiene. Also GR-S
or Buna-S. Most commonly used type of synthetic rubber. |
ScTP
|
Screened Twisted Pair. Premise network cable
with an overall foil shield. |
SDI
|
Serial Digital Interface. |
SDSL
|
Symmetric Digital Subscriber Line. |
SEALPIC
|
Aluminum Shield. Sealed Aluminum. |
Self-extinguishing
|
The characteristic of a material that
extinguishes its own flame after the igniting flame is removed. |
Self-Support
|
Undulated core with aluminum, polyethylene and
a support strand. For aerial use. |
Semi-Solid Dielectric
|
A coaxial design in which a monofilament of
plastic holds the center conductor in place in a hollow plastic tube
allowing the remainder of the dielectric to be air. Typical velocities of
up to 84% can be achieved in this design. |
Semiconductor
|
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. |
Separator
|
Pertaining to wire and cable, a layer of
insulating material such as textile, paper, Mylar, etc., which is placed
between a conductor and its 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
|
Digital information that is transmitted in
serial form. SDI informally refers to serial digital television signals
that conform to the SMPTE 259M standard. See also Serial Digital
Interface. |
Serial Digital Interface
|
Informally refers to serial digital television
signals that conform to the SMPTE 259M standard. |
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 and laid parallel around a cable core in
only one direction, as opposed to the two directions with interleaving of
a braid shield. |
Sheath
|
Pertaining to wire and cable, the outer
protective covering, also called jacket, that may also provide additional
insulation. |
Shield
|
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. |
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 or prevent signal leakage out of the cable.
Frequently confused with the term shield coverage. |
Shield Percentage
|
The percentage of physical area of a circuit
or cable actually covered by shielding material. |
Shielded Armored
|
Types of Shield: Aluminum, Aluminum/Steel,
Gopher, and Copper. Cables that require some sort of shield. |
Signal
|
Any visible or audible indication which can
convey information. Also, the information conveyed through a communication
system. |
Signal Conductor
|
A conductor in a transmission cable or line
that carries electrical signals. |
Signal to Noise Ratio
|
Ratio of desired signal to undesired signal
(noise) that is often expressed in decibels. Commonly used interchangeably
with Attenuation Crosstalk Ratio (ACR) - the difference between
attenuation and crosstalk, measured in decibels, at a given frequency.
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. |
Silicone
|
General Electric trademark for a material made
from silicon 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. |
Single-ended
|
Unbalanced, such as grounding one side of a
circuit or transmission line. |
Sinusoidal
|
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. |
SMA
|
Subminiature A connector commonly used in VHF,
UHF, and microwave RF applications. |
SMB
|
Subminiature B connector snap-mount connector. |
SMC
|
Subminiature C connector. |
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. |
SNMP
|
Simple Network Management Protocol. |
SNR
|
Signal to Noise Ratio (see also). |
SONET
|
Synchronous Optical Network. |
Source
|
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. |
Spacing
|
The distance between the centers of two
adjacent conductors. Pitch. |
Span
|
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. |
Spectrum
|
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 )
|
Approximately 2.998 x 10^8 meters per second. |
Splitter
|
A device that send the signal from one source
to two or more receiving devices by allocating a portion of the signal to
each receiver (e.g. cable TV splitter). 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. |
SRL
|
Structural Return Loss. |
Stalpeth (DUCTPIC)
|
Aluminum steel bonded to the polyethylene
jacket. Helps minimize jacket damage. |
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. |
Standing Wave Ratio (SWR)
|
A ratio of the maximum amplitude to the
minimum amplitude of a standing wave stated in current or voltage
amplitudes. See also Standing Wave. |
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. |
STP
|
Shielded Twisted Pair(s). |
Strain Gauge
|
A device for determining the amount of strain
(change in dimensions) when a stress is applied. |
Strand
|
A single uninsulated wire. |
Stranded Conductor
|
A conductor composed of groups of uninsulated
wires. |
Strip
|
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
|
Magnitude of the internal cable reflections,
measured in decibels, relative to the actual cable impedance, not the
system impedance. Measure of signal reflections caused by the structure of
the cable without the additional reflections from any impedance mismatch
between the cable and the measuring equipment. Measure of internal cable
reflections using a reference impedance in the measuring equipment that is
adjusted to the nominal or average impedance of the cable. See also Return
Loss |
Surge
|
A temporary and relatively large increase in
the voltage or current in an electric circuit or cable. Also called
transient. |
S-VHS
|
Abbreviation for Super VHS. A video format in
which the two parts of the video signal, the chrominance and luminance,
are recorded and played back separately providing for better picture
quality. (Not to be confused with S-Video which is a transmission
method). |
S-Video
|
Transmission method for video in which the two
parts of the signal, the chrominance and luminance, are sent on separate
transmission lines to provide better picture quality. (Not to be confused
with S-VHS which is a videotape recording method). |
Sweep Test
|
Testing a characteristic of a cable or device
across a range of frequencies. In cable, it usually implies return loss or
structural return loss (see also). |
TCP/IP
|
Transmission Control Protocol/Internet
Protocol. |
TDMA
|
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. |
Tefzel
|
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 or cable may be used in continuous operation without
change of its basic properties. |
Tensile Strength
|
The pull stress required to break a bare wire. |
TFE
|
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. |
Thermoplastic
|
A material which will soften, flow, or distort
appreciably when subjected to sufficient heat and pressure. Examples are
polyvinyl chloride and polyethylene. |
Thermosetting
|
A material which will not soften, flow, or
distort appreciably when subjected to heat and pressure. Vulcanizable.
Examples are rubber and neoprene. |
TIA
|
Telecommunications Industry Association. Body
which authored the TIA/EIA 568A "Commercial Building Telecommunications
Wiring Standard" in conjunction with EIA. |
TIA-EIA 568B
|
"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. |
Tinsel
|
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. |
TP-PMD
|
Twisted Pair-Physical Medium Dependent. |
Transducer
|
A device for converting one form of energy to
another, such as 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
|
An arrangement of two or more conductors, a
coaxial cable, or a waveguide used to transfer signal energy from one
location to another. |
Transmission Line Cable
|
Two or more conductors placed within a
dielectric material in such a way as to control the electrical
characteristics. |
Transmitter
|
The electronic package that converts
electrical energy to light energy in a fiber optic system. Also refers to
equipment that generates RF or electrical signals for transmission through
the air or space or over a transmissions line. |
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. A coaxial cable
with a second braid applied over an inner jacket and an outer jacket
applied over the outer braid. Commonly used in television camera systems. |
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. |
Turn-key
|
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. |
TVRO
|
TV Receive Only. |
Twin-lead
|
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. |
Twinax Cable
|
Cable with two twisted conductors with
established electrical properties (one pair=twinax). |
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. |
UHF
|
Ultra High Frequency. International
Telecommunication Union designation for the 300-3000 MHz band of
frequencies. |
UL
|
Underwriters Laboratories. A nonprofit
organization which tests and verifies construction and performance of
electronic parts and equipment, including wire and cable. |
UM
|
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. |
Unilay
|
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. |
UTP
|
Unshielded Twisted Pair(s). |
V
|
Volt (see also). |
VA
|
Volt-ampere. Measure of apparent power in a
reactive circuit found by multiplying the voltage by the current. |
VC/MTM
|
Variable Constellation/Multi-Tone Modulation. |
VDSL
|
Very 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. |
VHF
|
Very High Frequency. International
Telecommunication Union designation for the 30-300 MHz band of
frequencies. |
VHS
|
Abbreviation for Video Home System. VHS is a
trademark of Panasonic, Inc. |
Video
|
Pertaining to picture information in a
television system. |
VLF
|
Very Low Frequency. International
Telecommunications Union designation for the 3-30 kHz band of frequencies. |
Volt
|
A unit of electromotive force. |
Voltage
|
Electrical potential of electromotive force
expressed in volts. |
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
|
Ratio of maximum voltage of the standing wave
to the minimum voltage of the standing wave. See also Standing Wave Ratio. |
VSWR
|
Voltage Standing Wave Ratio. |
VW-1
|
A flammability rating established by
Underwriters Laboratories for wires and cables that pass a specially
designed vertical flame test, formerly designed FR-1. |
W
|
Symbol for watt or wattage. |
Wall Thickness
|
The thickness of an insulation or jacket. |
WAN
|
Wide Area Network. |
Watt
|
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. |
Wavelength
|
The distance between positive peaks of a
signal. As the frequency increases, and waves get closer together, the
wavelength decreases. |
WCS
|
Wireless Communications Service. |
Wire
|
A conductor, either bare or insulated. |
Wireless
|
Really a misnomer. Belden makes a variety of
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. |
X
|
Symbol for reactance. |
XLPE
|
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. |
XLR
|
A multi-pin audio connector (typically 3 pins)
used in microphone, line level and snake cable audio connections. |
XPE-PVC
|
Expanded Polyethylene-Polyvinyl Chloride. Fire retardant. |
Z
|
Symbol for impedance |
