CATV Training Institute

CATV Glossary

 Term AKA Description
1080 interlaced1080iCategory of HDTV video, a pixel resolution of 1080 horizontal lines x 1920 vertical lines.
1080 progressive1080pA set of HDTV high-definition video modes characterized by 1080 horizontal lines of vertical resolution and progressive scan, as opposed to interlaced, as is the case with the 1080i display standard. The term usually assumes a widescreen aspect ratio of 16:9, implying a resolution of 1920x1080 (2.1 megapixel) often marketed as Full HD.
480 Interlaced480i480i refers to interlaced video encoded with 240 line fields, forming a final Frame 480 Pixels tall.
480 progressive 480pRefers to progressive video encoded in frames 480 pixels tall. 480p is generally used for video from film sources, as they're natively progressive. It can also consist of interlaced video that's been deinterlaced for a number of possible reasons. Most 480p video comes from either DVD or deinterlaced TV captures.
720 progressive 720p720p (aka HD) is a progressive HDTV signal format with 720 horizontal lines and an aspect ratio (AR) of 16:9 (1.78:1). All major HDTV broadcasting standards The number 720 stands for the 720 horizontal scan lines of image display resolution (also known as 720 pixels of vertical resolution), while the letter p stands for progressive scan.
A/B SwitchA/B SwitchA device that allows two RF/coaxial devices to connect to a single source. Connecting only one device at a time. An A/B switch can also be used to connect one of two signal sources to a receiving device
Aerial CableCable suspended in the air on poles or other overhead structures. Usually implies the use of a "messenger strand"" to which the cable is lashed for support.
Aerial trespassExisting service drop that crosses over one property to serve another. Aerial trespass can usually be avoided by using a mid-span attachment.
All Digital SimulcastADS Cable operators use digital encoders to encode and convert all analog programs to digital at the headend. The encoded programs are then multiplexed and sent along with the existing digital channels throughout the network to the network edge, also known as the hub or local headend.
AnalogTechnology originally designed for transmitting voice (e.g., telephones) where signals are sent as electromagnetic waves. For video service, the signal is sent from the television broadcaster to the local cable operator to the subscriberís home. Along the way, there are a series of amplifiers; however, the manner in which the signal is sent is analogous to making a photocopy of a photocopy of a photocopy so that by the time the signal gets to the subscriberís home, the quality of the picture or audio may not be as clear as the original, meaning there may be snow or noise interference (compare Digital).
Aspect RatioRefers to the ratio of width to height of a picture. Standard definition television uses a 4:3 aspect ratio. High definition television uses a 16:9 aspect ratio.
AttenuationThe reduction of signal power through a given length of cable, air or space, a passive device, or connector. A general term that refers to any reduction in the strength of a signal. Attenuation occurs with any type of signal, whether digital or analog. Sometimes called loss, attenuation is a natural consequence of signal transmission over long distances. The extent of attenuation is usually expressed in units called decibels (dBs).
Audio/VideoAVAV, an abbreviation for audio/video, is frequently used as a generic term for the audio and video components and capabilities in home entertainment system and related product descriptions and reviews.
BandwidthThe width of an RF communications channel or a specified frequency range, typically expressed in units of hertz (kilohertz, megahertz, etc.). In digital communications, bandwidth is analogous to data capacity or throughput, typically expressed in units of bits per second (kilobits per second, megabits per second, etc.
Banjo clipAn inline phone adapter that connects to a standard modular telephone connection. It allows an easier connection for a telephone test phone or butt-set, a multimeter or other test devices to check phone circuits. Once installed, the technician does not have to take the jack apart to test the circuit.
Bit Error RateBERThe ratio of how many bits received in error over the number of total bits received.
BroadbandA transmission medium that allows transmission of voice, data, and video simultaneously at rates of 1.544Mbps or higher. Broadband transmission media generally can carry multiple channels- each at a different frequency or specific time slot.
BroadcastA broadcast is a service that is delivered to all customers. Each customer may select a particular broadcast channel out of many.
Buried CableA cable installed in the earth without the use of underground conduits.
Butt-setA lineman's handset is a special type of telephone used by technicians for installing and testing local loop telephone lines. A test telephone that can be connected to an analog telephone service at various locations on the phone line or customer premises interior wiring. The test set is able to perform a number of test functions such as checking for dial tone, making/receiving a call or monitoring a call. It is also called a test set, or "Combo".
Cable CardA removable security module (in a PCMCIA or PC card form factor) which, when inserted in an Open Cable certified set-top box (STB), television or other device, enables delivery of digital video programming and other services.
Cable compression toolA specialized tool used to install a compression-type F-connector onto the end of coaxial drop cable, by pressing the compression ring portion of the connector into the F-connector body.
Cable locatorSpecialized equipment used to locate, identify and mark the burial path of underground utilities such as electricity, water, gas, telecommunications and other facilities or services. Usually consists of a battery- powered transmitter and receiver pair.
Cable lossAttenuation or reduction of signal power in coaxial cable of a specific length, at a specific frequency, at a specific temperature.
Cable ModemCMAn electronic interface between a cable network and personal computer or other device, converting RF signals on the cable network into baseband digital data and vice versa. Typically used to deliver high-speed Internet service to cable subscribers.
Cable NetworkRefers to the cable television plant that would typically be used for data over cable services. Such plants generally employ a downstream path in the range of 54 MHz on the low end to a high end in the 550 to 1006 MHz range and an upstream path in the range of 5 to 42MHz. Customers share a common communication path for upstream and a separate common path for downstream.
Cable preparation tool (stripper)A specialized tool used to trim the jacket, shield, and dielectric of the coaxial drop cable to the correct dimensions in preparation for F-connector installation.
Cable-Ready TelevisionA television receiver that can receive unscrambled cable television channels without the use of a converter.
Cable TiltThe increase in cable attenuation as the frequency increases.
Cable TVA communications system which distributes broadcast programs and original programs and services by means of a coaxial cable.
Cable trespassingSimilar to aerial trespass; occurs when the buried subscriber drop cable crosses neighboring property lines.
Carrier FrequencyThe main frequency on which a voice, data, or video signal is sent.
Carrier to Noise RatioC/NThe ratio of the received carrier power and the noise power in a given bandwidth, expressed in dB. The higher the C/N, the better the received picture.
Carrier-to-Noise Ratio or Signal to NoiseCNR or C/N or SNRSignal-to-Noise Ratio, the ratio of the amplitude of the desired signal to the amplitude of noise signals at a given point in time. The larger the number, the better. Usually expressed in dB.
Category 1CAT1An unshielded, twisted pair (UTP) cable suitable for analog voice or POTS (plain old telephone service).
Category 3CAT3An unshielded, twisted pair (UTP) cable generally characterized to support 16 MHz of bandwidth and applications up to 10 Mbps.
Category 5CAT5An unshielded, twisted pair (UTP) cable that is the most common inside wire used today for telephone and data circuits. CAT5 is manufactured to comply with codes established by ANSI (American National Standards Institute) and is most commonly terminated with an RJ-45 connector. Also known as Cat 5.
Center ConductorThe centermost feature of coaxial cable, it consists of a solid copper or copper clad aluminum wire. Signals travel along the outside of the center conductor (Skin Effect) also known as the inner conductor or stinger.
ChannelA transmission path between two points. The term channel may refer to a one-way path or, when paths in the two directions of transmission are always associated, to a two-way path.
Closed systemA shielded network, such as one that uses coaxial cable for signal transmission, in which frequencies inside of the cables may be used for the carriage of entirely different signals than what may exist on the same frequencies in the over-the-air environment.
Coaxial CableCopper or copper-sheathed aluminum wire surrounded by an insulated layer of polyethylene foam, used by cable television systems. The insulating layer is covered with a tubular shielding composed of tiny strands of braided copper wire, or a seamless aluminum sheath, and protective outer skin. The wire and the shielding react with each other to setup an electromagnetic field between them. This system reduces frequency loss and gives cable its great signal-carrying capacity.
Common groundUse of the same ground or grounding electrode system to ground the electrical system, ground conductor enclosures, equipment, and separate services in or at a building.
Component VideoAn analog video signal that has been split into two or more component channels. In popular use, it refers to analog video information transmitted as three separate signals on three separate cables: Y for luminance and sync; PB for the difference between blue and luminance (B minus Y); and PR for the difference between red and luminance (R minus Y). Usually color-coded green for Y, blue for PB and red for PR. Considered to be higher video quality than composite video and S-video. Component video cables do not carry audio information.
Composite VideoAn analog video signal in which the color information is used to phase and amplitude modulate a color sub-carrier, and is transmitted on one cable, ready to modulate an RF carrier. Usually color- coded yellow and uses an RCA connector. Considered to be a lower video quality than S-video and component video. Composite video cables do not carry audio information.
ConverterDevice that is attached between the television set and the cable system that can increase the number of channels available on the TV, enabling it to accommodate the multiplicity of channels offered by cable TV. (Set-Top Box).
Crimp ToolA tool used to provide retention of an ""F"" type connector onto the braid and jacket of a coaxial cable.
Customer Premises EquipmentCPEEquipment located at the end-user or customerís premises, for example, any converter (set-top box), satellite dish and receiver, television, home theater amplifier, remote control device, cable modem, MTA, eMTA, tuner, terminal,†router, telephone, PBX switch, fax machine, etc. The term is usually used to refer to devices supplied by the cable operator, but sometimes the term is used to refer†to consumer electronics regardless of who owns the equipment.
Cumulative Leakage IndexCLIA snapshot of a cable network's signal leakage performance at a given point in time. A standard measurement of system leakage; when cable network equipment, coaxial cable, and connectors are imperfectly shielded signals leak out of the system (egress). Signal egress interferes with radio communications services and is of particular concern when it affects aeronautical navigation and communication services.
DecibeldBThe standard unit used to express the ratio of two power levels. It is used in communications to express either a gain or loss in power between the input and output devices.
Decibel milliVoltdBmVA measure of signal amplitude. Decibels relative to one millivolt across a given impedance (75 ohms in North American cable systems).
Demarcation PointDEMARCThe connection between the equipment and facility or between outside plant facilities and premises distribution
Diagnostics screen(s)A display of operating parameters and other information that may be used for maintenance and troubleshooting purposes.
DielectricA non-conductive insulator material between the center conductor and the shield of coaxial cable. which may be made of solid polyethylene, plastic discs or spacers.
Digital 5.1 Surround SoundSometimes referred to as Dolby Digital, an industry standard surround sound audio codec designed to deliver 5.1 channels of audio to cable, broadcast and satellite TV programming as well as DVDs, Blu-ray discs and PCs. Sound is decoded and sent to 6 loudspeakers; left front, center (for dialog), right front, left surround (rear) and right surround (rear), and a low frequency effects loudspeaker (or sub-woofer). Dolby Digital, Dolby Pro-Logic II, DTS, and SDDS are all Dolby 5.1 systems.
Digital CableA collection of channels which are transmitted in the form of binary code, zeros and ones, and used to enhance cable TV service and/or two-way high-speed data.
Digital converterA set-top box that can receive, demodulate, and in many instances also decrypt digital signals, and provide an analog and/or digital output signal to a TV or other video equipment. Models are available for cable, satellite, and over-the-air applications. Commonly called a digital set-top box or simply a set-top.
Digital Set-top BoxDSTB A device which accepts digital encoded television broadcasts and converts them to display on an analog television. Also known as a Converter.
Digital Terminal AdapterDTAA low cost set-top box deployed by cable companies that provides digital service from the cable to analog TVs or digital TVs via coax cable input. It has only 2 coax connectors: in from the cable; out to the TV. It does not support a digital program guide or video-on-demand.
Digital Video InterfaceA widely used digital interface between a computer and monitor. DVI connectors are found on many TVs, Blu-ray and DVD players, data projectors and cable and satellite set-top boxes. It was designed as a digital replacement for the analog VGA standard.
Digital Video RecorderA consumer device which uses a hard disk drive to record television programs.
Direct BuriedThe placement of coaxial, fiber optic, twisted pair telephone or power cable underground without any extra protective sheath, duct or conduit.
Direct currentDCAn electrical current that is unidirectional, as a result of a voltage source whose output maintains the same polarity of output voltage. An example includes the output of a battery.
Directional CouplerA passive signal splitting device, with minimum signal loss between the input port and the output port ( referred to as ""through loss""), a specified couping loss between the input port and the tap port (tap loss), and very high loss between the output port and the tap port (isolation).
Disconnect(s)The complete discontinuance of a customerís service at a given address, most commonly accomplished by physically disconnecting the subscriber drop cable from the tap (or splitter in a MDU box). Referred as DISCO.
Disconnect tagAn identification tag attached to a subscriber drop cable near the tap (or splitter in a MDU box) that signifies a service status of "disconnected" or inactive.
Distribution PlantThe hardware of a cable system--amplifiers, trunk cable and feeder lines, attached to utility poles or fed through underground conduits like telephone and electric wires.
Downgrade(s)The discontinuance of a premium program service or any other service or product, removing it from the existing level or tier of cable service.
Downstream (forward)The direction of RF signal transmission from headend to subscriber. In North American cable networks, the downstream or forward spectrum occupies frequencies from 54 MHz to as high as 1002 MHz.
DownstreamDSFlow of signals from the cable system control center through the distribution network to the customer. RF signal from the headend/hub to the subscriber, also known as forward path.
Drip loopA downward loop in the subscriber drop cable, formed at the span clamp, tap, house hook, ground block, splitter, and entry hole into the house or structure. Its purpose is to direct water away from connectors, the structure, and the cable entry point.
Drop AmplifierAn amplifier installed at a subscriber location to provide RF-signal adjustment (including gain, RF power level and frequency tilt), RF signal splitting, and filtering as required to maintain acceptable operator network performance. Also known as a "house amplifier".
Drop cableA relatively small diameter, flexible coaxial cable used from a tap at the pole or pedestal to and inside of the subscriber premises. Common drop cable designations include 59-series, 6-series, and 11-series, each formerly known as RG-59, RG-6, and RG-11 type cables respectively.
Drop hangerAlso called a drop clamp, or drop wire clamp. This metal device serves as the terminating point for the subscriber drop cableís messenger support wire when installing an overhead coaxial cable drop. Instead of tying off the drop cableís messenger wire to the house attachment or span clamp directly, the messenger is tied off to the drop hanger, which in turn is hooked onto the house attachment device or span clamp via the bail wire on the drop hanger.
Drop tagThe system-provided identification tag(s) attached to the subscriber drop cable at the tap (or splitter in a MDU box). Information on the tag can include street address, serial number, unit number, connection status (such as active, inactive, repeat offender, trap installed), tech number. Sometimes a
Dual TunerUsually related to a dual-tuner DVR that can record two programs to the DVR hard drive at the same time, or one program can be viewed while another is being recorded. Or the user can view a pre-recorded program while the two tuners are recording other programs.
Easement(s)A right that one entity may have to access or use the real property of another entity without owning or possessing the real property. For example an easement may grant right of way access for telecommunications, electric, gas, water, sewer, and other equipment or facilities.
EgressA condition often called "signal leakage" in which signals carried by the distribution system radiate into the air.
Embedded multimedia terminal adapter eMTAeMTAA cable modem is a type of network bridge and modem that provides both bi-directional data communication via radio frequency channels on a hybrid fiber-coaxial (HFC) and RFoG infrastructure.
Estimated Time to Arrival ETAEstimated Time to Arrival
F-ConnectorThe final piece of hardware on a coaxial cable. It is cylindrical with a center pin sticking out, that plugs into the set-top box, cable ready TV or VCR.
Federal Communications CommissionFCCFederal agency responsible for the regulatory oversight of the communications infrastructure in the United States.
Feeder CableCoaxial cables that run along streets within the served area and connect between the individual taps which serve the customer drops.
Feeder LineCable distribution lines that connect the main trunk line or cable to the smaller drop cable.
FilterA circuit that selects the frequency of desired channels. Used in trunk and feeder lines for special cable services.
FittingsAnother name for the connectors used on coaxial cable. For example, the F-connectors used on series 6 cable are often called "fittings".
Flooded cableCable which is designed for underground placement that is infused with a viscous waterproofing material between the jacket and shield, inhibiting the ingress of moisture should the cable jacket be damaged. This cable may also be known as filled cable.
Free on DemandFODFree video content that can be watched at any time.
Freeze frames (freezing)When a digital signal has too many errors for a receiver to correct in one or more error frames of the video, the preceding frame will be displayed until the receiver is able to display a new video frame. This causes the picture to appear to stop (or freeze) momentarily.
FrequencyA measure of the number of complete cycles of energy occurring over a unit of time, usually one second. Frequency as it relates to electromagnetic signals is generally expressed in hertz (Hz) or cycles per second (CPS).
Funnel EffectA cable TV term that relates to the accumulation of signals, noise and distortions in the upstream plant as a result of many points communicating with one common point, for instance, from multiple subscriber locations back to the node, hub site, or headend.
GhostingIn analog television, a superimposed and offset replica of the transmitted image. Causes include reflections due to impedance mismatch(es), multi-path, or ingress from another signal source on the same channel.
Grainy PictureA poor picture condition, usually the result of weak signal strength and a uniform distribution of noise, appearing as spots or streaks throughout the picture.
Ground1. A connection to, or to contact with earth, or connection to some extended conductive body that serves instead of or in place of earth. 2. An intentional connection to earth through a conductor or conductors of sufficiently low impedance and having sufficient current carrying capacity to prevent the buildup of voltages that may result in undue hazards to connected equipment or to persons.
Grounding electrode systemConcrete-encased electrode within and near the bottom of a foundation or footing in direct contact with the earth, a metal underground water pipe that is in direct contact with the earth for at least 10 feet or more, the metal frame of the building and/or a ground ring encircling a building or structure and in direct contact with the earth, when bonded together, comprise a grounding electrode system.
Ground RodIron, copper-clad steel, stainless steel, or stainless steel-clad rod that is driven into earth for the purpose of providing a connection to earth. Also called a made electrode.
HeadendThe electronic control center of a cable system. This is the site of the receiving antenna and the signal processing equipment essential to proper functioning of a cable system.
High DefinitionHDA video format with a high resolution for better picture quality.
High-bandwidth Digital Content ProtectionHDCPA form of digital copy protection used to prevent copying of digital audio and video content as it travels across connections.
High-Definition Multimedia InterfaceHDMIA compact audio/video interface for transmitting uncompressed digital data. One cable will support uncompressed TV or PC video, including standard, enhanced and high-definition video, up to 8 channels of compressed or uncompressed digital audio. HDMI connects devices such as cable and satellite set-top boxes, DVD and Blu-ray disc players, PCs, camcorders, and video game consoles to compatible PC monitors, video projectors, tablet computers and digital televisions.
High Definition TelevisionHDTV(Also referred to as HDTV): Improved television system that provides approximately twice the vertical and horizontal video resolution of existing standards and audio quality approaching that of compact discs. The result is an enhanced picture and audio quality.
Home-health certificationSome test equipment can be used to perform whole home certifications, also known as home health certification. The actual name of the certification may vary but the goal is the same: to automatically perform critical subscriber drop tests to ensure the in-home network is performing properly and within specification.
Home runA method of installing wiring or cabling that involves a separate wire or cable from a common point to multiple points or outlets within the building or structure. Also called star wiring or star architecture.
Horizontal BarsHUMRelatively broad horizontal bars, alternately black and white, which extend over the entire picture. They may be stationary, or may move up or down. Caused by approximate 60-cycle interfering frequency, or one of its harmonic frequencies.
Hybrid Fiber/Coaxial CableHFCA cable network featuring optical fiber from a headend location to a neighborhood node, and coaxial cable from the node to individual homes
Infrared blasterIR blasterA device that emulates an infrared remote control to autonomously control a device that is normally controlled only by†remote control keys. This is typically used by a recording device such as a DVR or VCR to change the channel on an external tuner such as a cable box or satellite receiver. Another use would be muting the stereo or TV in the office with a mouse click on the userís PC.
IngressIn cable telecommunications, the term used for over-the-air signals (unwanted) entering the cable network through shielding defects (loose connectors, cracked cable, etc.). The opposite of signal leakage or egress.
Insertion lossA measure of the attenuation of a device by determining the output of a system before and after the device is inserted into the system; the loss of signal level in a cable path caused by the insertion of a passive device.
Inside Wiring IWCustomer's wire that is attached to the home whether it is coaxial, telephone twisted pair, cat5 or electrical.
Interactive programming guide IPGA guide with increased interactive features, such as allowing users to sort through onscreen TV listings by time, or channel, or themes, like children's shows and program a VCR or TV directly from within the guide.
Interactive Voice Response SystemIVRTechnicians add, remove equipment from a customer account, update account information, code out jobs. Interactive computer generated dispatch operator.
J-hookA galvanized steel hook that is driven into a utility pole to support a subscriber drop cable attachment.
Local Number PortabilityLNPTo reassign a phone number to another carrier.
Locking TerminatorA theft-proof connector used in a cable system where it becomes necessary to terminate RF signal.
Locking terminatorA device that serves two purposes: 1) to secure an unused tap port, preventing unauthorized connection, and 2) to terminate the unused tap port with a 75 ohm impedance to minimize reflections at the tap. The locking terminator is difficult to remove without a special tool designed for the specific locking terminator.
Locking terminator toolA specialized tool used to install or remove a locking terminator.
Loop throughA method of installing wiring or cabling in which the cable is placed from an origination point to the first outlet location, then another cable placed from the first outlet location to a second outlet location and so on. Also called series wiring.
Messenger cableA cable that has a support wire (messenger) that is embedded in the cableís jacket. This term is usually used in reference to drop cable although messenger hard-line cables, sometimes called "Figure 8," are available.
Messenger wireThe supporting steel wire that is embedded into the jacket of an overhead subscriber drop cable. It supports and provides strain relief for the coaxial portion of the drop cable and is used to attach the cable at each end.
Messenger wrapThe specifications for tying a drop cable messenger wire to an attachment device, such as†a span clamp, house hook or drop hanger. Specifications may include the number of wraps around the attachment device, the number of wraps around the messenger itself, and the number of wraps around the coax and messenger together.
Mid-span drop attachments Mid-spanRefers to the area between two utility poles. A mid-span connection involves the placement of a span clamp somewhere "mid-span" so the subscriber drop cable can be routed from the tap to the mid-span clamp and from there to the building or another structure.
Modem provisioningA number of steps a cable modem must go through for activation and authorization.
Multimedia over Coax AllianceMoCAÆMoCA technology runs over the existing in-home coaxial cabling, enabling whole home distribution of high definition video and content.
Multiple Dwelling UnitMDUA classification of housing where multiple separate housing units for residential (i.e. non-commercial) inhabitants are contained within one building or several buildings within one complex. A common form is an apartment building. Sometimes units in a multi-family residential building are condominiums, where typically the units are owned individually rather than leased from a single apartment building owner.
Network Interface DeviceNIDA device that serves as the demarcation point between the carrier's local loop and the customer's premises wiring. Outdoor telephone NIDs also provide the subscriber with access to the station wiring and serve as a convenient test point for verification of loop integrity and of the subscriberís inside wiring. Generically, an NID may also be called a Network Interface Unit (NIU), Telephone Network Interface (TNI), System Network Interface (SNI), or telephone network box.
Output channelA frequency or range of frequencies at the output of a device such as a set-top, to which a connected television or other receiver is tuned in order to receive programming. A common set-top output channel is Ch. 3 or 4.
Outside PlantOSPThe portion of the fiber optic or coaxial network that exists outside of central exchange buildings.
Over-the-airOTAAlso called off-air, a television signal that has been broadcast through the air.
Passive deviceRequires no power for its intended function. Example; splitters, directional couplers, taps and attenuators.
Pay-Per ViewPPVProgramming, typically movies or special events, that a subscriber specifically requests to receive for a single fee added to the monthly cable bill. Some cable operators have the capability of determining whether the pay-per-view program was purchased via telephone or by on-screen interactive remote control and whether the converter channel was then set on the appropriate movie channel in order to receive the programming. Rates for pay-per-view programming are not regulated.
PedestalPedA metal, fiberglass or plastic enclosure used to protect and secure cable telecommunications active devices, passive devices and splices from the environment. It is typically above ground, attached to a stake that holds it in place and is locked to prevent tampering and theft of equipment and services. A company-provided key is required to enter.
Personal protective equipmentPPERefers to protective clothing, hard hats, eye protections, clothing, or other garments or equipment designed to protect the wearerís body from injury by blunt impacts, electrical hazards, chemicals, heat, and infection, for job-related occupational health and safety purposes, and in combat, martial arts, sports, etc.
P-hookA steel screw-eye with a threaded portion on one end and a "P-shaped" hook at the other end, commonly used for subscriber drop cable attachment to a building or structure.
Picture in a PicturePIPPicture-in-Picture. A feature of some television receivers and similar devices, displaying one program on the full TV screen at the same time one or more other programs are displayed in an inset window. Two independent tuners and signal sources are required.
Plain old telephone servicePOTSThe voice- grade telephone service that remains the basic form of residential and small business service connection to the public telephone network.
PlantA general term applied to any of the physical property of a service company which contributes to the furnishing of power or communication services. Also referred to as cable plant.
Point of Entry (PoE) for MoCA filterA low-pass filter used to improve the performance of MoCAÆ. It prevents MoCA signals (typically above 1 GHz) in one home from interfering with MoCA devices in neighboring homes. A PoE filter is most effective when installed at the ground block or input to the first splitter on the home.
Polarity1. In a telephone circuit, polarity refers to the "tip" and "ring" side of a circuit. Tip is generally the ground (positive) side and ring is the battery (negative) side of the circuit. Corrosion of the copper that is heavily used in phone circuits is reduced in this "positive ground" technique. Tip is generally color-coded green and ring is red. Polarity reversal (crossing tip and ring) on some older equipment will allow a user to achieve dial tone and receive phone calls, but will not allow the user to break dial tone and call out. Most modern telephone devices are designed to operate correctly in spite of this problem, except when special circuits such as DID (direct inward dialing) trunk circuits, T-1 lines and ground-start lines are utilized. 2. In the electrical domain, electric charges considered to be either positive or negative polarity are present in every electrical circuit. Electrons flow from the negative pole to the positive pole. In DC (direct current) circuits, one pole is always positive and one is always negative, however in AC (alternating current) circuits, the polarity and direction of electron flow continuously reverses. 3. In more general terms, polarity refers to the distinction between positive and negative, north and south, anode and cathode, horizontal and vertical, etc.
Post wiredDescribes wiring or cabling that was installed after the building construction was completed, typically routed on the exterior of the building and/or through crawlspaces, basements and attics.
Power over EthernetPoETransmitting electrical power along with data on Ethernet cabling. This allows a single cable to provide both data connection and electrical power to devices such as wireless access points.
Power InserterAn electronic device that allows voltage to be put on a coaxial cable line so as to provide power to various amplifiers and electronic devices.
Premium ChannelsChannels not included in a cable operator's regular service tiers. HBO and Showtime are examples of premium channels. In order to obtain premium channels, cable operators are allowed to require that the subscriber purchase the basic service tier, rent or purchase a converter box, and pay additional fees. Rates for premium channels are not regulated.
Pre-wiredWiring or cabling that was installed while the building was under construction, typically routed through the framing (studs, plates) of the building, which conceals the cabling within the walls, floors, and ceilings.
Quadrature amplitude modulationQAMA modulation technique in which an RF signalís amplitude and phase are varied to convey information such as digital data. The word "quadrature" indicates that amplitude and phase can be represented in rectangular coordinates as in-phase (I) and quadrature (Q) components of a signal. The number that often accompanies "QAM," for example, 64-QAM, indicates the number of states or combinations of amplitude and phase, each of which represents a symbol.
Radio FrequencyRFAnalog electrical signals sent over cable. Conventional (broadcast) television and radio, as well as cable TV, deliver RF signals to your television or radio.
Red, Green, BlueRGBA pixel is made up of these colors, the greater the number of pixels, the better quality the digital video resolution or picture quality.
Return PathUpstream (return)RF signal transmission in the direction from the subscriber to the headend. The upstream spectrum occupies the following frequencies 5 MHz to as high as 50 MHz.
RF signal levelA measure of the power of an RF signal, typically expressed in dBmV.
Ringer equivalence numberRENIn telecommunications, a REN is a somewhat arbitrary number which denotes the electrical load a telephone ringer applies to the line. Known in some countries outside the U.S. as the RAL (Ringer Approximated Loading). The local phone company usually sets a limit of 5 REN or less for a total of all the devices connected to the line and each phone or fax machine can range from 0.1 REN to 1.0 REN.
RJ-11The standard connector utilized on 2-pair (4 wire) telephone wiring to interface a telephone, fax machine or telephone modem. RJ stands for "Registered Jack" and it is the interface most often used for telephone jacks in the U.S. as well as other countries. Though it has a total of six wire positions, typically either only two or four are actually utilized. It comes in two standard varieties: untwisted (silver satin cable) used between the phone handset and the base, and UTP (Unshielded Twisted Pair) used between the phone base and the phone jack or outlet.
RJ-14See RJ-11. The same connector as an RJ-11 although RJ-11 usually connects two conductors to support one phone line, however RJ-14 is used to connect four conductors to support two phone lines, or six conductors to support three phone lines. Line one "ring" is the red or blue/white wire, and "tip" is the green or white/blue wire. Line two "ring" is yellow or orange/ white, and "tip" is black or white/orange. Line three "ring" is blue or white/green and "tip" is white or green/white.
RJ31-XHome security systems have a DACT (digital alarm communicator transmitter) or controller that monitors circuits for alarm conditions. When a circuit reports an alarm the system terminates any active use of the customerís phone line and "seizes the line", via a relay known as the RJ31-X. Once the line has been "seized" the DACT will automatically dial the security monitoring center.
RJ-45The standard connector utilized on 4-pair (8 wire) UTP (Unshielded Twisted Pair) cable including CAT- 5 and CAT-5e. It is generally implemented for network and telephone cabling and is the standard connector for Ethernet, ISDN, T-1 and modern digital telephone systems. RJ stands for "Registered Jack".
Second audio programSAPAlso called secondary audio programming, SAP is an auxiliary audio channel that can be transmitted or broadcast both by cable and over the air.
Security shield toolA specialized tool used to tighten or loosen an F-connector when installed with a security shield or sleeve.
Security sleeve or shieldA metal or plastic collar that is placed between the subscriber drop cableís F-connector and a mating port to inhibit tampering of the connection. A special tool is then used to tighten or loosen the F-connector.
Service callAn on-site visit (truck roll) made by a technician to troubleshoot and repair a problem, often in response to a subscriber complaint or request. Also known as a trouble call.
Service call percentageA metric with which to track all service calls or a category of service calls during a specified period of time. For example, monthly service call percentage is defined mathematically as S% = (SM/ CM) * 100, where S% is service call percentage, SM is the number of service calls being tracked in a one month period, and CM is the average number of subscribers in that same month.
Set-Top BoxEquipment authorized by and often provided by a cable operator in a subscriber's home that allows access to or controls interference from cable services
Set-top boxSTBAn electronic device that is installed between a signal source such as a cable network and a television. Also known as a set-top, the device may include one or more tuners for channel selection, demodulator, descrambler or decoder, modulator, support for on-screen graphics display, and†digital video recorder (DVR) functionality. Early set-tops were called converters, and included little more than a tuner and perhaps a descrambler for premium content access.
Signal leakageThe undesired emission or egress of RF signals inside of a cable network into the over-the-air environment. Typical causes of signal leakage include loose, improperly installed, corroded or otherwise damaged connectors; cracked or otherwise damaged coaxial cable shielding; loose passive device faceplates; loose or warped amplifier housing lids; and other problems that affect or degrade the shielding integrity of the cable network.
Signal level meterSLMA specialized piece of test equipment used to measure the RF signal levels or power in dBmV of selected channels or signals.
Signal-to-Noise RatioSNR1) The ratio of signal power to noise power, expressed in decibels. 2) In the context of analog baseband video, the ratio of the peak-to-peak video amplitude (excluding sync) to the root mean square amplitude of noise within that video signal, expressed in decibels.
Skin effectThe behavior whereby electricity migrates to the outside wall of a wire.
SlingBoxA television content streaming device made by Sling Media. It uses proprietary Sling Player software to encode video and audio over the Internet.
Span clamp, drop clamp, Q-span clampA device that is used to attach a subscriber drop cable to the strand, comprising two functional halves: the clamp and the hook. The clamp assembly is manufactured to fit the galvanized steel strand that the hard-line cables are lashed to. The hook portion supports the subscriber drop cable steel messenger wire, or a preformed drop cable attachment device. Also named "C-span clamp" and "O-span clamp," describing the shape of the hook portion.
SplitterA passive device (one with no active electronic components) which distribute television signal carried on a cable in two or more paths and sends it to a number of receivers simultaneously.
Standard Definition TelevisionSD or SDTVA digital television system that offers a resolution that is not considered to be either enhanced-definition television (EDTV) or high-definition television (HDTV). In the US, resolution is 480i (interlace scanning) and it is broadcast in a 4:3 aspect ratio.
Switched Digital VideoSDVAllows cable providers the ability to save bandwidth by sending requested channels on an "as needed" basis to users one at a time. Cable operators can potentially offer a greater number of channel offerings to compensate for not having to broadcast unwatched programs when not required to do so.
StrandThe galvanized (zinc coated) steel wire, typically 1/4", 5/16", or 3/8" diameter that serves as the support mechanism for overhead cable and/or fiber plant. The hard-line coaxial cables, fiber cables, amplifiers, taps and other passive devices are all lashed or clamped to the strand.
StreamingGenerally refers to a delivery method in which multimedia is continuously transmitted or presented to an end user, delivered by a streaming provider. An example of streaming is broadcasting media in real-time over the Internet.
SubscriberSubA cable customer. A household or business that legally receives and pays a cable and/ or pay television service for its own use.
S-VideoAlso referred to as Super Video, Separate Video, and Y/C. An analog video transmission scheme in which video is encoded on two channels: luma/ intensity (Y), and chroma/color (C). Used primarily to connect consumer electronic devices, its video quality is considered to be better than Composite Video (encoded on one channel) but less than Component Video (encoded on three channels). The 4-pin min-DIN connector is the most common of the several S-Video connector types. S-Video cables do not carry audio information.
TapA device which splits off a portion of the feeder line signal for the subscriber.
TerminatorA resistive load for an open coaxial line to eliminate reflections.
Throughput LossIn a coupler where the splitting ratio between output ports is not equal, the output port containing the greater power.
TilingAn unpleasant, mosaic-like effect from the moving of digital video image rectangular areas into locations that are different than their intended positions on the screen. Signal impairments can be a factor.
Tone and ProbeFox and houndA technique and related equipment typically used to trace telephone wire pairs or other communications cables on non-active networks. A tone generator or "fox" is connection to the telephone circuit pair at one end and an inductive probe or "hound" is used to locate the same pair up to many miles away.
Torque wrenchA 7/16" open-end wrench that is calibrated to click or "break" at a factory preset torque rating, Used to properly tighten a coaxial cable F-connector to a desired pre-set torque.
TrapA filter that blocks one or more signals, channels, or frequencies, while passing other signals, channels, or frequencies.
Trunk CableCables that carry signal from the headend to groups of subscribers. The cables can be either coaxial or fiber depending on the design of the system.
Twisted pairA type of wiring that may be shielded or unshielded, in which two conductors are twisted together for the purpose of reducing electromagnetic interference from external sources. If the twist rate varies among the wire pairs in a given cable, crosstalk between neighboring pairs also may be reduced.
Universal remoteA remote control that can be programmed to operate various brands of one or more types of consumer electronics devices.
V ChipSystem that is built into television sets and allows users to screen out, based on television ratings, programs they do not want household members to watch. Those subscribers with older television sets may need to purchase a set-top box that utilizes V-Chip technology in order to access this feature.
Video Cassette RecorderVCRThe videocassette recorder is an electro-mechanical device that records analog audio and analog video from broadcast television on a removable, magnetic tape videocassette, so that the images and sound can be played back at a more convenient time.
Video on DemandVoDSystems which allow users to select and watch/listen to video or audio content on demand using interactive commands. Television VOD systems either stream content through a set-top box, a computer or other device, allowing viewing in real time, or download it to a device.
Voice over Internet ProtocolVoIPThe delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet.
Wall fishThe process of installing wiring or cabling in a finished wall cavity, usually requiring a hole through the top or bottom plate in the framing, through which the†wire will pass inside the wall cavity.





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