Fiber Optic Center Glossary
There are currently 380 names in this directory beginning with the letter S.
The frequency spectrum from 2 GHz to 4 GHz used for land based microwave and some mobile satellite communications. The “short” DWDM transmission band, which occupies the 1460-1530 nm wavelength range.
S-MAC Serial Multiplexed Analog Component
A proposed standard for television transmission. The signal uses time compression and time domain multiplexing to transmit luminance and color difference signals as a single channel signal.
Safe Working Voltage
Limit of continuous voltage for cable operation. Usually specified at 70% of Corona Extinction Voltage.
That feature of a connector design which permits safety wiring of plug and/or receptacle to prevent the loosening or vibrating free of the plug from the receptacle.
A means of safety wiring a plug and/or receptacle to prevent the loosening or vibrating free of the plug from the receptacle.
The distance measured vertically from the fiber optic cable to the straight line joining two points of support. Unless otherwise stated, the sag referred to is at the mid-point of the span.
A section of line between two dead-end structures. One or more of these sections may be present in a stringing section.
A span selected within a sag section used as a control to determine the proper sag, and therefore tension of the fiber optic cable. At least two and normally three sag spans in a sag section, are required to sag a section properly. This may be increased where span lengths vary greatly and/or the terrain is hilly or mountainous.
The tension at which the fiber optic cable is designed to be installed. Usually at the initial sag.
Surface-mounted or flush-type wall cabinets for housing circuit administration hardware. Satellite cabinets, like satellite telecommunications closets, supplement riser telecommunications closets by providing additional facilities for connecting horizontal cables from information outlets in user work areas. Sometimes referred to as a "satellite location".
Satellite Telecommunications Closet
A walk-in or shallow wall closet that supplements a riser telecommunications closet by providing additional facilities for connecting riser backbone cables to horizontal cables from information outlets. Also referred to as a "satellite location". See also Riser Telecommunications Closet.
Subscriber connector, a push/pull connector style that is recognized as the preferred optical fiber connector standard. It is available in simplex, duplex, hybrid, or hardened styles. The SC (Subscriber Carrier) fiber optic connector is one of three connectors (the other two are ST and SFF) approved by ANSI/TIA/EIA 568-B.3. The SC Connector’s main advantage is polarization since the connectors can be paired and keyed.
Property of glass that causes light to deflect from the fiber and contributes to optical attenuation. The change of direction of light after striking small particles that causes loss in optical fibers.
Connectors with long shell design to insure proper alignment during mating, thus avoiding damaged pins or electrically shorted contacts. (MIL-STD)
A cable core design where an aluminum shield divides the cable core into two electrically separate compartments.
Ratio of the power fed into a coaxial cable to the power transmitted by the cable through the outer conductor.
A screw attached to one half of a two-piece multiple contact connector used to draw and hold both halves together and to separate them. (MIL-STD) Also called Jackscrew
When an optical fiber is slightly scratched and then broken (scribing) to achieve a 90° endface. For splicing, the scribe tool needs to cleave as close as possible without angles, chips, or cracks. These tools are more expensive than hand scribe tools used for connectorization, where the final polish will be performed by machine or hand.
A strand construction having one size of cover wires with the same number of one size of wires in the inner layer and each layer having the same length and direction of lay
A plug that is inserted to fill an unoccupied contact aperture in a connector insert. Its function is to seal, especially in environmental connectors.
A nonconductive material that protects the conductor against abrasion and provides a second electrical barrier. A high resistance dielectric material which is placed over primary insulation to protect it from abrasion.
A cable run. Its maximum length is determined by the topology. A 10BASE2 segment may be up to 605 feet long. A 10BASE-T segment may be up to 328 feet long.
A stranded conductor consisting of three or more stranded conducting elements, each element having approximately the shape of the sector of circle, assembled to give a substantially circular cross-section.
The application of plating material to a limited portion of a connector contact, especially those areas susceptible to wear.
The tendency of leads to center themselves on solder pads due to the surface tension of the liquid solder.
The characteristic of a material whose flame is extinguished after the igniting flame is removed.
Self Normal Jack
A jack that provides a connection between the two rear connectors, except when interrupted by the insertion of a video patch plug into the front panel receptacle.
Self Terminating Jack
A jack that automatically provides a 75 ohm termination on the circuit that is connected to the rear connector, except when a plug is inserted into the receptacle on the front panel.
Self-healing ring (SHR)
A system architecture consisting of two counter-rotating directions for communications between nodes. In normal use, the data traffic is sent in both directions. In the event of a broken fiber in one of the fiber loops, the data will reach the affected remote device via the other fiber ring. In this way, data traffic can still travel to all surviving sections of the ring, even if the path is via a longer fiber route.
Self-Supporting Aerial Cable
A cable consisting of one or more insulated conductors factory-assembled with a messenger which supports the assemblage and which may or may not form a part of the electrical circuit.
Any assemblage of conductors which incorporates a steel rope or steel sheath for added tensile strength, thus enabling it to be suspended between widely spaced supports.
Pertaining to an adhesive that undergoes vulcanization without the application of heat.
A jacket having a sufficiently low resistance so that its outer surface can be kept at substantially ground potential by a grounded conductor placed under the jacket.
A tape of such resistance that when applied between two elements of a cable, the adjacent surfaces of the two elements will maintain substantially the same potential. Such tapes are commonly used for conductor shielding and in conjunction with metallic shielding over the insulation.
A jacket having a sufficiently low resistance so that its outer surface can be kept at substantially ground potential.
A cable consisting of a tin-filled braid outer conductor which will allow repeated flexure without damage. It will not hold a stable shape but is able to be hand bent.
A cable containing a flexible inner-core and a relatively inflexible sheathing material, such as a metallic tube, but which can be bent for coiling or spooling and placing in a duct or cable run.
An insulation cross-section having a partially open space between the conductor and the insulation perimeter.
A material that has a resistance characteristic between that of insulators and conductors. 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.
A state of immune response in which further exposure elicits an immune or allergic response.
A term used to describe an adhesive consisting of two parts, one part being applied to one adherend and the other part to the other adherend and the two brought together to form a joint.
A layer of insulating material 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.
Metric or footage designations located at periodic locations on the outer jacket of cables.
Serial Data Transmission
Data transmission between computer devices using only a single circuit path. Whole bytes of information (8 bits) are sent in sequential pattern. Compares with parallel transmission. Parallel transmission is often used internally within computing devices because of the higher processing speeds which are possible, but for long-distance telecommunication, serial transmission is more economic in terms of line plant.
Serial Digital Video Transmission
Transmission of a video signal by a series of discrete "on-off" or "high-low" pulses.
Normally a DB 9 pin connector located on the mother board of a PC. A technique in which each Bit of information is sent sequentially on a single channel.
A device used in high-speed communications that converts data between serial and parallel data streams. Used to combine and separate multiple video and/or data channels to and from a single channel data stream. See TDM.
A circuit in which the components are arranged end-to-end to form a single path for current.
Deformation of the inside surface of a conductor barrel to provide better gripping of the conductor or on the outside of the connector body to provide better gripping of the connector. (MIL-STD)
Served Wire Armor (SWA)
Spiral wrap of soft galvanized steel wires applied to a cable to afford mechanical protection and increase the cable pulling tension characteristics.
A network device which provides a service to other network devices. Services include file, printer, communications or gateway.
(a) Allowing for “slack” in a splice tray, closure, or vault to accommodate future needs. (b) When a device is terminated to the wire in the communications outlet, a fair amount of “slack” should be left on the wire and wound in the box to accommodate future trimming when devices are changed out.
The maximum voltage or current which a connector is designed to carry continuously. (MIL-STD)
A wrapping applied over the core of a cable or over a wire. Servings may be in the form of filaments, fibers, yarn, tape, etc. Often referred to as a binder.
Layer 5 of the OSI model. Responsible for establishment and control of dialogues between users on different machines. Synchronization for reliable data transfer and token management to control use of the connection are services provided by this layer.
To convert an adhesive into a fixed or hardened state by chemical or physical action, such as condensation, polymerization, oxidation, vulcanization, gelation, hydration, or evaporation of volatile constituents.
The temperature to which an adhesive or an assembly is subjected to set the adhesive. (See also curing temperature and drying temperature.)
The period of time necessary for an adhesive in an assembly to set under specified conditions of temperature or pressure, or both.
An interconnecting device in which the mating parts are exactly alike at their mating surfaces. Also called "Hermaphroditic Connector".
Shear adhesion failure temperature (SAFT)
Refers to the upper temperature limit at which an adhesive is able to support a certain amount of weight. Polymer degradation, incorrect raw material ratios and incorrect blending can affect the SAFT results. This is not a measure of the bond between the adhesive and a substrate, but a measure of the internal strength of the adhesive itself. Generally, as the shear strength of an adhesive system in increased, tack and adhesive performance will decrease.
An adhesive joint, the maximum average stress when a force is applied parallel to the joint. (See bond strength.)
Test to measure resistance to shear stress by bonding the ends of flat bars in an overlapping position.
The combination of a metallic shield and an extruded plastic jacket applied as the outermost covering on a cable. In the absence of a shield, the extruded jacket may be designated as a sheath. The material, usually an extruded plastic or elastomer, applied outermost to a wire or cable to provide mechanical and environmental protection. Very often referred to as a jacket. A common term for the collection of twisted pairs of multipair cables. The outer covering or jacket of a multiconductor cable.
A sheave wheel, complete with arm or frame, should be suspended from structures to permit stringing of fiber optic cables. The sheaves must be lined with urethane or neoprene and have a diameter as required in specifications for each type of fiber optic cable being installed for normal vertical suspension points. For increased deflection angles, large diameter sheaves or multiple sheave assemblies are required.
A pair of wires, twisted together and covered with a conductive material to provide any potentially induced noise a quick path to ground.
The period of time, usually beginning with the date of manufacture, during which a stored adhesive will remain effective or useful. Same as storage life.
Shell Electrical Connector
The outside case of a connector into which the dielectric material and contacts are assembled. (MIL-STD)
1) A conducting housing or screen that substantially reduces the effect of electric or magnetic fields on one side thereof, upon devices or circuits on the other side. Cable shields may be solid, braided, or taped (longitudinally or spirally). 2) In cables, a metallic layer placed around a conductor or group of conductors to prevent electrostatic or electromagnetic interference between the enclosed wires and external fields.
In cables, a metallic layer placed around a conductor or group of conductors to prevent electrostatic interference between the enclosed wires and external fields. Also see Insulation Shield.
An intermediate device that allows the termination of the cable shield to the connector shell.
The physical area of a cable that is covered by the shield ing material and is expressed in percent.
A set of two shields in which one shield is adjacent to and surrounds another shield. Dual shields provide higher shield effectiveness over a broader range of frequencies. They typically consist of a foil shield, surrounded by either a spiral strand or braid shield.
The relative ability of a shield to screen out undesirable interference. Frequently confused with the term Shield Coverage.
Shield Electrical Connector
An item especially designed to be placed around that portion of a connector which contains facilities for attaching wires or cables. It is used for shielding against electrical interference or mechanical injury and usually has provisions for passage of the wire. (MIL-STD)
Cable that is protected from electromagnetic and radio-frequency interference by a metal sheathing. The shield may be composed of braided strands of copper (or other metal).
A cable or group of wires enclosed within a conductive shield to minimize the interference effects of internal or external circuits.
A contact which carries alternating current and is shielded from unwanted signals (RFI and EMI). Generally, these contacts are not impedance matched.
A transmission line whose elements confine propagated radio waves to an essentially finite space inside a tabular conducting surface called the sheath preventing the line from radiating radio waves .
A room made free from EMI by applying shielding to floor, walls and ceiling surfaces and by suppressing any interference entering through the power lines
Shielded Twisted Pair Cable (STP)
An electrically conducting cable comprising one or more elements each of which is individually shielded. There may be an overall shield in which case the cable is referred to as a shielded twisted pair cable with an overall shield.
Strands or tapes of conductive material, which can be formed into a braid, or spiral wrap, or longitudinal cover, around insulated conductors or cable to reduce signal interference. Typical shielding materials are copper, tin or silver plated copper and aluminum.
The relative capability of a shield to screen out undesirable electric and magnetic fields and plane waves. The measurement is the ratio of the signal received without the shield to the signal received inside the shield.
A physical barrier, that is usually electrically conductive, that reduces the interaction of electric of magnetic fields upon devices , circuits, or portions of circuits.
A material used to maintain shielding effectiveness across a seam or gap in an electronic enclosure. It may be made from a variety of materials including fabric-wrapped foam, wire mesh, stamped metal and elastomer compounds.
1) An abrupt impact applied to a stationary object. 2) An abrupt or non-periodic change in position, characterized by suddenness, and by the development of substantial internal forces
A test to determine the ability of a cable to withstand a violent physical concussion such as might occur during handling or use.
An unintended connection between 2 or more parts. This failure indicates insufficient insulation between metal conductors which were not intended to be connected.
A condition that exists when two conductors are connected ahead of where they normally should be in a circuit. This causes reduced resistance and sometimes the undesirable side effects.
A connector device designed to mate with a receptacle connector to perform protective, environmental and/or electrical shorting functions. Also called Dummy Connector Plug
An expression of how much the inside diameter of shrink tubing will reduce in size when recovered. The inverse of the expansion ratio.
That temperature which effects complete recovery of a shrinkable product from the expanded state.
Tubing which has been extruded, cross-linked, and mechanically expanded which when reheated will return to its original diameter.
The ratio between the expanded diameter and recovered diameter of shrinkable products.
The portion of a barrel similar to an insulation grip except that it is not compressed around the conductor insulation. (MIL-STD). Also called Insulation Support.
An atom or a group of atoms (in addition monomers) bonded to one of two double-bonded carbon atoms (Example: "Cl" in CH2=CHCl)
Side Wall Bearing Pressure (SWBP)
A term used in reference to the pressure on a cable which is being pulled around a curved surface under tension. If excessive, SWBP can damage cable components and reduce the life of the cable.
1) An electrical impulse of a predetermined voltage, current, polarity and pulse width. Used to convey information, either digital, analog, audio or video. 2) A current used to convey information, either digital, analog, audio or video.
A cable designed to carry current of usually less than one ampere per conductor to operate signal circuit devices.
Signal To Noise Ratio (SNR)
The ratio of the signal magnitude to the noise magnitude and is usually expressed in dB. The higher the SNR of a system, the better is its performance.
Signal-to-noise ratio (SNR)
The ratio of the power of the signal versus the power of the background noise, usually measured in decibels. Describes the quality of an electronic transmission system.
Signaling System 7 (SS7)
An out-of-band signaling system that provides basic routing information, call setup and other cell termination functions. Signaling is removed from the voice channel and put on a separate data network.
Silica Glass (Fiber Optic)
Glass made mostly from silica (silicon dioxide, SiO2) used to make fibers.
A semiconductor that used absorbed photon energy to stimulate carriers from one energy level to a higher one. The change in charge across the junction is monitored as a current in the external photodiode circuit. Silicon photodetectors are commonly used in multimode systems operating at 850 nm.
1) A material made from silicone and oxygen. It can be in thermosetting elastomer or liquid form. The thermosetting elastomer form is noted for high heat resistance; 2) A thermosetting Elastomer with excellent heat-resistant. Polymeric materials in which the four recurring chemical groups contain silicon and oxygen atoms at links in the main chain.
A pressure-sensitive adhesive capable of functioning effectively at extreme temperatures.
A silicone liquid treatment applied to insulated conductors to allow for easy jacket stripping.
General Electric trademark for a material made from silicone and oxygen. Can be in thermosetting elastomer or liquid form. The thermosetting elastomer form is noted for high heat resistance.
A highly conductive metal with atomic number 47. When applied as terminal plating, it provides a hard-oxide soft-base finish that requires only moderate pressure for a metal-to-metal contact. Silver plating is normally used on metals that are relatively good conductors such as copper and brass.
Flat, untwisted cable used typically as a telephone extension cord. It should never be used in a Local Area Network.
Simple/signalling network management protocol (SNMP)
Network management architecture initially designed for the Internet but easily applied or extended to any network type.
Transmission in only one direction. Generally a communications system or device capable of transmission in one direction only.
A tight buffered breakout cable with only one fiber. Single-longitudinal mode (SLM) laser A laser, usually distributed feedback (DFB) type, where the spectral width is the width at the 20 dB down points dividedby 6.07.
Simulation results have shown that 40 Gigabit Ethernet may be possible at 50 meters (164 ft) and 100 Gigabit Ethernet at 15 meters (49 ft). In 2007
researchers at Pennsylvania State University predicted that either 32 nm or 22 nm circuits would allow for 100 Gigabit Ethernet at 100 meters(328 ft).
One covalent bond (one shared pair of electrons between two atoms), represented by "-" (Examples: C-C, C-O)
Single Mode Fiber
A fiber wave guide in which only one mode will propagate. The fiber has a very small core diameter of approximately 8mm. It permits signal transmission at extremely high bandwidths and is generally used with laser diodes.
A plastic-coated fiber surrounded by an extruded layer of plastic encased in a synthetic strengthening material, and enclosed in a plastic sheath.
A chain that comprises units always joined to each other through one single atom on only one of the units. (IUPAC)
Optical fiber with a small core diameter in which only single mode is capable of propagation. 8.3 micron is the common standard core size.
A method of introducing a light pulse into a single light ray (mode) into an optical fiber. Singlemode is typically used for long-haul applications of 2 to 50 kilometers using relatively expensive laser light sources usually operating at a 1310 or 1550 nanometer wavelength.
Fusion of a spirally applied tape wrap jacket by the use of high heat to a homogeneous continuum. Usually employed for fluorocarbon, non-extrudable materials.
Varying in proportion to the sine of angle or time function. Ordinary alternating current is sinusoidal.
Application of a material (sealer, size) to the surface of an adherend, prior to that of the adhesive, in order to reduce the absorbency of the adherend.
Widely separated braid of fiber copper, or steel, used to hold core together, for reinforcing jacket or for shielding.
Filled tape coated on one or both sides with a thin film of uncured rubber or synthetic compound to produce a coating suitable for vulcanization.
1) The phenomenon in which the depth of penetration of electric currents into a conductor decreases as the frequency increases. 2) The tendency of alternating current, as its frequency increases, to travel only on the surface of a conductor.
A braided, knifed, or woven tube used over wires or components as insulation tubing. Also called Sleeving.
Short lengths of rigid metal pipe, approximately 4 in. (10.1 cm) in diameter, located in riser telecommunications closet, that allows cables to pass from floor to floor when closets are vertically aligned. Sleeves also provide for easy pulling of cable.
Wire ropes made into forms, with or without fittings, for handling loads and so made as to permit the attachment of an operating rope
A very flexible sling composed of several individual wire ropes braided into a single sling
Openings in the floor of riser telecommunications closets that allow cables to pass thorough from floor to floor when closets are vertically aligned. A slot accommodates more cables than an individual sleeve.
A slotted tongue for sliding onto the screw or stud so that neither screw nor unit needs removing. (MIL-STD)
SMA (Subminiature A)
50 ohm - subminiature coaxial connector with screw type coupling mechanism. Frequency range DC-18 GHz.
Small form factor (SFF)
A connector that offers higher density electronic equipment, enclosures, and distribution panels, lower connector costs, easier termination, and better optical performance.
Smoke Density Rating
Test methodologies of various organizations designed to simulate smoke density generated during flame and burning and the results of a material when tested under a specific methodology. Several tests are typically used: NBS Smoke Density per ASTM E662, OSU per FAR 25, NBS Smoke Density per ISO 5659, IF index per NFF 16 or Smoke Density per NFX 10. Smoke density is designing to evaluate the visibility for escape from a burning area.
SMPTE Recommended Practice
Advisory operating information issued by the SMPTE, as differentiated from a Standard.
Used to describe the easy removal or assembly of one part to another. A connector containing socket (female) contacts into which a plug connector having male contacts is inserted.
The principle of the angle of incidence when light passes through materials with differing refractive indices.
A connector containing socket contacts into which a plug connector having male contacts is inserted.
Socket Contact Sleeve
A sleeve that holds the contact spring in the correct position within the socket contact.
For plug-in devices, for use on panel boards, printed circuit boards and microelectronic components. (MIL-STD)
The process of changing a measurement from inch-pound units to equivalent metric units within acceptable measurement tolerances without changing the physical configuration of the items.
Soft Cure, AL-32xx Series
ÅngströmLink® materials with a consistency approximating Jell-O (Shore 00 ~ 30). Used for bulk encapsulation where the low modulus provides stress relief from mismatches in thermal coefficients of expansion. Good adhesion to a variety of substrates and a range of refractive indices to couple the light between the two materials of the joint.
The temperature at which an adhesive goes from a solid to a molten form, measured in Fahrenheit or Celsius.
A metal or metal alloy, usually having a low melting point, used to join other metals having higher melting points than the solder.
A contact or terminal with a cup, hollow cylinder, eyelet or hood to accept a wire for a conventional soldered termination.
A tubular end of a terminal in which a conductor is inserted prior to being soldered. It is also the hollow cylinder at the rear of a solder contact where a wire is inserted and soldered in place.
A solder type contact provided with a hole at its end through which a wire can be inserted prior to being soldered. (MIL-STD)
The end of a terminal or contact in which the conductor is inserted prior to being soldered. (MIL-STD) Also called Solder Cup
A heat-shrinkable tubing device containing a predetermined amount of solder and flux used for environmental resistant solder connections and shield termination.
An electrical/mechanical connection device that is used to terminate a discrete wire or wire3s by soldering. (See also "Solder Terminal, Bifurcated," "Cup Solder Terminal", "Hock Solder Terminal", "Perforated (Pierced) Solder Terminal, and "Turret Solder Terminal")
Solder Terminal , Hook
A solder terminal with a curved feature around which one or more wires are wrapped prior to soldering.
Solder Terminal, Bifurcated
A solder terminal with a slot or slit opening through which one or more wires are placed prior to soldering.
Solder Terminal, Cup
A cylindrical solder terminal with a hollow opening into which one or more wirews are placed prior to soldering.
Solder Terminal, Hook
A solder terminal with a curved feature around which one or more wires are wrapped prior to soldering.
Solder Terminal, Turret
A round post-type stud (stand-off) solder terminal with a groove or grooves around which one or more wires are wrapped prior to soldering.
Solder Type Connector
A connector in which the contact between the conductor and the connector is made by a soldered joint.
A process of joining metallic surfaces with solder without the melting of the base metals. Soldering is an economical, versatile and fast termination method. A soldered connection has metallic continuity and, therefore, excellent long term reliability.
Tool with an internal heating element used to heat surfaces being soldered to the point where the solder becomes molten.
Shrinkable tubing with a solder preform used for high-test reliability soldering connections or shield grounding.
The joining of two metals by pressure means without the use of solder, braze or nay method requiring heat. (MIL-STD)
A contact with a back portion that is a hollow cylinder which allows it to accept a wire. After a bared wire is inserted, a crimping tool is applied to crimp the contact metal firmly against the wire. Usually called a crimp contact.
A technique of connecting stripped solid wire to a terminal post containing a series of sharp edges by winding the wire around the terminal. (MIL-STD)
An adhesive having a volatile organic liquid as a vehicle. Discussion—This term excludes water-based adhesives.
The ability of a material to retain physical and electrical properties after being immersed in specific solvents.
A dry adhesive on an adherend that is rendered tacky just prior to use by application of a solvent.
A light emitter, either an LED or laser diode, in a fiber optic link; a device that when properly driven will produce information carrying optical signals.
A bridge uses source routing when the route to be followed is carried within each frame by the source stations. The source station acquires and maintains information by a search process, allowing parallel bridges to exist and to share traffic between the same two rings.
All rubber, parallel-jacketed, two-conductor light duty cord for pendant or portable use in damp locations. 300 V
Same as SP-1, but heavier construction, with or without third conductor for grounding purposes. 300 V.
Denotes applications peculiar to spacecraft and systems designed for operation near or beyond the upper reaches of the earth's atmosphere. (MIL-STD). Another name for a binary "0" in data communications.
Spade Tongue Terminal
Slotted tongue terminal designed to slip around a screw or stud without removing the nut. (MIL-STD
1) In flat conductors, the distance between the reference edge of the first and the last conductor; 2) In round conductors, the distance between centers of the first and last conductors ; (3) In aerial cable, the distance between poles or support clamp
A test designed to locate pinholes in an insulated wire by application of an electrical potential across the material for a very short period of time while the wire is drawn through an electrode field.
Specialized Mobile Radio (SMR)
A private, mobile dispatch radio service that is usually used by businesses, such as taxi services.
The ratio of the weight of any volume of substance to a weight of an equal volume of some substance taken as a standard, usually water for liquids and hydrogen for gases.
The quantity of heat needed to raise the temperature of a mass of material as compared with the same amount of water.
Specific Inductive Capacity (SIC)
1)The ratio of the capacitance using the material in question as the dielectric, to the capacitance resulting when the material is replaced by air. 2)That property of a dielectric which determines the electrostatic energy stored per unit volume for a unit potential gradient. The ratio of the capacitance using the material in question as the dielectric, to the capacitance resulting when the material is replaced by air. The dielectric constant is the most important design parameter for coaxial cables and determines dimensions, losses and propagation characteristics. Also called Dielectric Constant
A document prepared specifically to support acquisition which clearly and accurately describes essential technical requirements for purchased material.
The difference between wavelengths at which the radiant intensity of illumination is half its peak intensity.
A full width half maximum (FWHM) measurement of a LED or laser light source to determine its optical width.
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 set test
A series of tests run to determine how fast a given glue can build strength under ideal conditions.
Spheres, SIOP (Fiber Optic Center)
ÅngströmSphere™ silica spheres are manufactured using our own proprietary technologies which allow the essential properties of amorphous silica to be combined with unique control of duplication, both in form and particle size.
a chain that comprises constitutional units, joined so as to form an uninterrupted sequence of rings through single common atoms between adjacent rings. (IUPAC)
An interconnection method for joining the ends of two optical fibers in a permanent or semi-permanent fashion. Maybe thermally fused or mechanically applied.
Splice (fusion or mechanical)
A device that provides for a connection between two fibers, typically intended to be permanent.
A cable and fiber management product that environmentally protects and houses optical splices. Available as in-line or butt style, the closure is usually in a dome or clamshell configuration. Splice closures can also hold connectors and optical splitters. Telcordia GR-771 specifies mechanical requirements and environmental specifications and tests.
A tray or other device used for the permanent storage of mechanical or fusion optical splices.
A rack or wall-mounted panel that allows cables to be organized and spliced. The panel holds splice trays, secures the cable, grounds any metallic members, and organizes and stores buffer tubes, fibers, and splices.
A device which is placed over the fusion splice to provide mechanical strength and protection to allow easy handling of the splice for organization in a splice tray or other storage. Two types are the heat shrink protector and the butterfly.
Interweaving of two ends of ropes so as to make a continuous or endless length without appreciably increasing the diameter. Also making a loop or eye in the end of a rope by tucking the ends of the strands
A situation that occurs when a twisted pair is misconnected so that it becomes _ of two separate pairs. The noise immunity of the twists is lost and an impedance mismatch is created. This wiring error will not show up as an error on a Wiremap, but will be indicated by very high NEXT. (also see also REVERSED PAIR and TRANSPOSED PAIR).
A fiber device that optically splits signals. The splitters used in a PON outside plant network are optical splitters that distribute optical signals from the OLT into the ONTs. Splitters used in FTTx installations are specified by the ITU G.671 standard as wavelength independent couplers (WIC), which provide the same attenuation regardless of wavelength or direction.
A revolvable flanged device made of wood or metal, used for winding flexible metal wire or cable.
The quantity of adhesive per unit joint area. Single spread refers to application of adhesive to only one substrate of a joint. Double spread refers to application of adhesive to both substrates of a joint.
Originally developed by the military because it offered secure communications, spread-spectrum radio transmissions essentially "spread" a radio signal over a very-wide frequency band in order to make it difficult to intercept and jam.
Spring Finger Action
Design of a contact as used in a printed circuit connector or a socket contact, permitting easy, stress-free spring action to provide contact pressure and/or retention.
A face glued construction that is approximately squared in cross section that will be turned on a lathe.
Type of connector used on fiber optic cable utilizing a spring loaded twist and lock coupling similar to the BNC connectors used with coaxial cabling.
The difference between the percentage power factor at 80 volts/mil and at 40 volts/mil measured on wire immersed in water at 750C for a specified time.
An adhesive additive which prevents or minimizes change in properties, e.g.., by adherend absorption, demulsification, or rapid chemical reaction.
A cable sheath consisting of a corrugated steel (ST) shield applied over a corrugated aluminum (AL) shield and an outer polyethylene (PETH) jacket.
Contacts made by stamping and bending sheet metal rather than by the machining of metal stock. Also called Sheet Metal Contacts
A document that establishes engineering and technical requirements for items, equipment, processes, procedures, practices and methods that have been adopted as standard. Standards may also establish requirements for selection, application and design criteria for material.
Specifications, standards, handbooks, QPL's and such other engineering records, drawings, purchase descriptions, etc., as are or may be utilized for comparable purposes
The amount of time a fully-charged wireless phone can be left on before its battery runs down.
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 along a transmission line is a result of reflected energy from an impedance mismatch
Standing Wave Ratio
A measure of the mismatch between the load the line. It is equal to 1 when the line impedance is perfectly matched to the load. (In which case the maximum and minimum are the same, as current and voltage do not vary along the line). The perfect match would be a 1 to 1 ratio.
Standing Wave Ratio (SWR)
In a transmission line, waveguide, or analogous system, a figure of merit used to express the efficiency of the system in transmitting power.
Shaped similar to a stapler, its blade is made from a material sharp enough to nick the fiber optic and, by pressing down on a flexible tongue, cleaving the fiber optic. Most often used in a cleave and crimp style connector, and for acceptance testing.
A physical point to point network topology. A topology for communications networks that involves transmission of data through a central location to other users.
An optical splitter in which many fibers have their signals mixed at a single optical element. The mixed signals are then transmitted back through all the fibers. The name comes from the geometrical arrangement; all fibers come together at a single point.
A macromolecule containing a constitutional unit from which more than two chains (arms) emanate. A star macromolecule with n linear chains (arms) attached to the central unit is termed an n-star, e.g., five-star. (IUPAC)
A cable element which comprises four insulated conductors twisted together. Two diametrically facing conductors from a transmission pair.
A topology in which each telecommunications outlet/connector is directly cabled to the distribution device.
In asynchronous communications, a start bit and stop bit delimits each character to indicate to the receiver the character’s location.
Used to denote the environmental conditions of an installed cable rather than the conditions existing during cable installation.
A conductor composed of single solid wires twisted together, either singly or in groups.
Signal distortion due to the electrical field radiated by a voltage source which has coupled into the signal-bearing circuit.
PVC jacketed wire specially designed for use in ducts or stapled to surfaces for direct connection to subscriber's phone.
A copolymer consisting of macromolecules in which the sequential distribution of the monomeric units obeys known statistical laws. An example for a statistical copolymer is one consisting of macromolecules in which the sequential distribution of monomeric units follows Markovian statistics. (IUPAC)
A component of a cable used to anchor the cable ends at their points of termination and to keep any pull of the cable f rom being transferred to the electrical connections.
Steady state modal distribution
Equilibrium modal distribution (EMD) in multimode fiber, achieved some distance from the source, where the relative power in the modes becomes stable with increasing distance.
A material usually specified for applications requiring unusually high mechanical strength. Steel is used as a base metal and protected by a suitable plating.
Step Index Fiber (Fiber Optic)
A multimode fiber consisting of a core of uniform refractive index surrounded by cladding of a slightly lower refractive index. Accepts light rays over wider angle, but has smaller bandwidth than single mode fiber. See also Graded Index Fiber and Single Mode Fiber.
A type of fiber where the refractive index of the core is uniformly higher than that of the surrounding cladding.
A block macromolecule composed of stereoregular, and possibly in addition non-stereoregular, blocks. (IUPAC)
A regular macromolecule comprising only one species of stereorepeating unit. (IUPAC)
A configurational repeating unit having defined configuration at all sites of stereoisomerism in the main chain of a regular macromolecule (or oligomer molecule or block). (IUPAC)
A device attached to a crimping tool to properly locate a terminal, splice or contact in the tool prior to crimping. See locator. (MIL-STD)
The period of time during which a packaged adhesive can be stored under specified temperature conditions and remain suitable for use.
Straight-Tip (ST) Connector
A fiber optic connector used to join single fibers together at interconnects or to connect them to fiber optic cross connects.
The disconnection of conductors from their termination points due to excessive axial stress.
A device for determining the amount of strain (change in dimensions) when a stress is applied.
A technique involving devices or methods of termination or installation which reduce mechanical stresses from being transmitted to the conductor termination.
Strain Relief Clamp
A mechanical clamp attached to the cable side of the connector to support the cable or wire bundle, provide strain relief and absorb vibration and shock otherwise transmitted by the cable to the contact/wire connection. (MIL-STD) Also called Cable Clamp
Strand Conductor Shield
A layer of semiconducting material or tape applied directly over the stranded conductor of cables rated 2,000 volts and higher. This reduces the possibility of high stress points occurring between the conductor and insulation.
A distance of advance of one strand of a spirally stranded conductor, in one turn, measured axially.
A strong woven-copper-wire cable used to support cable in aerial distribution systems. The cable is lashed to the stranded cable during installation.
A wire or cable constructed of several small strands of conductor instead of one larger solid piece. This configuration provides for more flexibility in certain applications. Patch cords are made out of stranded conductors and the NEXT values are degraded up to 20% to allow for them in a link.
Part of a fiber optic cable composed of aramid yarn, steel strands, or fiberglass filaments that increase the tensile strength of the cable.
The property of an adhesive that results in the formation of filaments or threads when adhesive transfer surfaces are separated. (See also legging and webbing.) (Compare teeth.) Discussion—Transfer surfaces may be rolls, picker plates, stencils, etc.
The force required to remove a small section of insulating material from the conductor it covers.
A type of transmission line configuration which consists of a single narrow conductor parallel and equidistant to two parallel ground planes.
A bonding agent used for transferring required loads between substrates exposed to service environments typical for the structure involved.
Structural Return Loss
Backward reflected energies from uneven parts of the cable structure causing impedance variations are termed structural return loss.
Flexible cabling scheme which allows rapid reconfiguration for office moves through patching.
A short cable (usually 25 ft [7.6 m] or less) that extends from a cable terminal, protector, or block and is used to make connections to such devices.
Subminiature type A (SMA) connector
A nonkeyed, noncontacting, multimode threaded connector borrowed from the coax industry. Types include 905, 906, or optimate.
Subscriber Identify Module
The "SIM card" is an integrated-circuit chip housed in a plastic card which enables a cellular subscriber to use any (usually Global System for Mobile Communications) handset. The card identifies and bills the caller, no matter whose phone is being used.
Subscriber line interface circuit (SLIC)
The line card that provides the interface between local loop and telco switching equipment.
A material upon the surface of which an adhesive-containing substance is spread for any purpose, such as bonding or coating. A broader term than adhered.
Condition of bond failure in which the substrate falls apart. The cohesive strength of the adhesive and the adhesive forces between the adhesive and substrate exceed the internal strength of the material being bonded.
Super physical contact (SPC)
The spherical endface polish of a ferrule and fiber that is performed on a polishing machine. Typically 50 dB return loss. Superseded by the UPC polish.
The racks, clamps, cabinets, brackets, trays, tools, and other equipment that provide the physical means to attach the transmission media and connecting hardware to walls or ceilings.
Surface Emitter LED
A LED that emits light perpendicular to the semiconductor chip. Most LEDs used in datacommunications are surface emitters.
Surface Mount Device (SMD)
An active or passive device designed to be soldered to the surface of the printed circuit board.
Surface Mount Technology (SMT)
The process of assembling printed circuit boards with components soldered to the surface rather than to plated through-holes.
The electrical connection of components to the surface of a conductive pattern without utilizing component holes in a circuit board.
A surface primer is a coating that changes the character of a surface so that an adhesive or coating will adhere to it more effectively.
The resistance of a material between two opposite sides of a unit square of its surface. It is usually expressed in ohms.
Surface-emitting LED (SLED)
A diode that emits light perpendicular to the semiconductor chip. Most LEDs used in data communications are surface emitting.
A ceiling that creates an area or space between the ceiling material and the structure above the material. Synonym: Drop Ceiling, Suspended Ceiling.
A method to determine the frequency response of a cable by generating an RF voltage whose frequencies varied at a rapid constant rate over a given range.
A device for re-routing signals from one optical fiber into others. Types include MEMs, matrix, bypass, optical cross connect, and electrical network switches.
A cable used within and between the central office main frames and the switchboard.
Switched multimegabit data service (SMDS)
A high-speed public packet switched data service that provides up to 155 Mb/s connectivity for LANs.
Switched video on demand (SVOD)
Television service provided over an established network but not continuously broadcast, therefore requiring less bandwidth than conventional broadcast systems. Signal transmission is initiated when a subscriber selects a channel, which triggers a request back to the service provider.
A function carried out by a switching hub, alleviating traffic by making virtual connections between transmitting and receiving nodes.
The method by which the bit patterns appearing on digital line systems may be properly "clocked" and interpreted�allowing the beginning of particular patterns and frame formats to be correctly identified.
Signals that are sourced from the same timing reference and hence are identical in frequency.
Synchronous Data Transfer
Data transfer employing a strictly regular pattern, rather than using start and stop bits to distinguish character patterns from idle line operation.
Synchronous digital hierarchy (SDH)
A worldwide, high-speed synchronous protocol standard transmitting at up to 10 Gb/s. Known as SONET in North America.
Synchronous optical network (SONET)
ANSI-standard physical interface defined by its optical line rates known as optical carrier (OC) signals, frame format and OAM&P protocol. Adopted by the ITU as SDH.
Synchronous transfer mode (STM)
A transport and switching method that depends on information occurring in regular and fixed patterns with respect to a reference such as a frame pattern.
A transmission method in which data characters are synchronized by timing signals generated at sending and receiving stations (as opposed to start/stop communications). Both stations operate continuously at the same frequency and are maintained in a desired phase relationship. Several codes may be used as long as they utilize the required line control characters. Also called �bi-sync� or �binary synchronous.�
Synchronous transport signaling (STS)
The transmission speed of a SONET transmission medium, e.g., OC-48.
A macromolecule comprising alternating enantiomeric configurational base units. Note in a syndiotactic macromolecule, the configurational repeating unit consists of two configurational base units that are enantiomeric. (IUPAC)
The equipment on a premises that provides functions common to terminal devices such as telephones, data terminals, integrated workstations terminals, and personal computers. Typically, the system-common equipment is the private branch exchange (PBX) switch, data packet switch, or central host computer. Often called common equipment.