1.
Wire
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A wire is a single, usually cylindrical, flexible strand or rod of metal. Wires are used to bear mechanical loads or electricity and telecommunications signals, Wire is commonly formed by drawing the metal through a hole in a die or draw plate. Wire gauges come in standard sizes, as expressed in terms of a gauge number. The term wire is used more loosely to refer to a bundle of such strands, as in multistranded wire. Wire comes in solid core, stranded, or braided forms, edge-wound coil springs, such as the Slinky toy, are made of special flattened wire. In some cases, strips cut from metal sheet were made into wire by pulling them through perforations in stone beads and this causes the strips to fold round on themselves to form thin tubes. This strip drawing technique was in use in Egypt by the 2nd Dynasty, from the middle of the 2nd millennium BCE most of the gold wires in jewellery are characterised by seam lines that follow a spiral path along the wire. Such twisted strips can be converted into solid round wires by rolling them between flat surfaces or the wire drawing method. The strip twist wire manufacturing method was superseded by drawing in the ancient Old World sometime between about the 8th and 10th centuries AD, there is some evidence for the use of drawing further East prior to this period. Square and hexagonal wires were made using a swaging technique. In this method a metal rod was struck between grooved metal blocks, or between a punch and a grooved metal anvil. Swaging is of great antiquity, possibly dating to the beginning of the 2nd millennium BCE in Egypt and in the Bronze and Iron Ages in Europe for torcs, twisted square-section wires are a very common filigree decoration in early Etruscan jewelry. In about the middle of the 2nd millennium BCE, a new category of decorative tube was introduced which imitated a line of granules. True beaded wire, produced by mechanically distorting a round-section wire, appeared in the Eastern Mediterranean and Italy in the seventh century BCE, a forerunner to beaded wire may be the notched strips and wires which first occur from around 2000 BCE in Anatolia. Wire was drawn in England from the medieval period, the wire was used to make wool cards and pins, manufactured goods whose import was prohibited by Edward IV in 1463. The first wire mill in Great Britain was established at Tintern in about 1568 by the founders of the Company of Mineral and Battery Works, apart from their second wire mill at nearby Whitebrook, there were no other wire mills before the second half of the 17th century. Despite the existence of mills, the drawing of wire down to fine sizes continued to be done manually. Wire is usually drawn of cylindrical form, but it may be made of any desired section by varying the outline of the holes in the draw-plate through which it is passed in the process of manufacture
2.
Electrical conductor
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In physics and electrical engineering, a conductor is an object or type of material that allows the flow of an electrical current in one or more directions. Materials made of metal are common electrical conductors, Electrical current is generated by the flow of negatively charged electrons, positively charged holes, and positive or negative ions in some cases. In order for current to flow, it is not necessary for one charged particle to travel from the producing the current to that consuming it. Instead, the particle simply needs to nudge its neighbor a finite amount who will nudge its neighbor and on and on until a particle is nudged into the consumer. Essentially what is occurring here is a chain of momentum transfer between mobile charge carriers, the Drude model of conduction describes this process more rigorously. Insulators are non-conducting materials with few mobile charges that support only insignificant electric currents, the resistance of a given conductor depends on the material it is made of, and on its dimensions. For a given material, the resistance is proportional to the cross-sectional area. For example, a copper wire has lower resistance than an otherwise-identical thin copper wire. Also, for a material, the resistance is proportional to the length, for example. The resistance R and conductance G of a conductor of uniform cross section, therefore, the resistivity and conductivity are proportionality constants, and therefore depend only on the material the wire is made of, not the geometry of the wire. Resistivity and conductivity are reciprocals, ρ =1 / σ, resistivity is a measure of the materials ability to oppose electric current. This formula is not exact, It assumes the current density is uniform in the conductor. However, this still provides a good approximation for long thin conductors such as wires. Another situation this formula is not exact for is with alternating current, then, the geometrical cross-section is different from the effective cross-section in which current actually flows, so the resistance is higher than expected. Similarly, if two conductors are each other carrying AC current, their resistances increase due to the proximity effect. Aside from the geometry of the wire, temperature also has a significant effect on the efficacy of conductors, temperature affects conductors in two main ways, the first is that materials may expand under the application of heat. The amount that the material will expand is governed by the expansion coefficient specific to the material. Such an expansion will change the geometry of the conductor and therefore its characteristic resistance, however, this effect is generally small, on the order of 10−6
3.
Electrical connector
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An electrical connector, is an electro-mechanical device used to join electrical terminations and create an electrical circuit. Electrical connectors consist of plugs and jacks, the connection may be temporary, as for portable equipment, require a tool for assembly and removal, or serve as a permanent electrical joint between two wires or devices. An adapter can be used to bring together dissimilar connectors. There are hundreds of types of electrical connectors, connectors may join two lengths of flexible copper wire or cable, or connect a wire or cable to an electrical terminal. In computing, a connector can also be known as a physical interface. Cable glands, known as cable connectors in the US, connect wires to devices rather than electrically and are distinct from quick-disconnects performing the latter. It is usually desirable for a connector to be easy to visually, rapid to assemble, require only simple tooling. In some cases an equipment manufacturer might choose a connector specifically because it is not compatible with those other sources. No single connector has all the properties, the proliferation of types is a reflection of differing requirements. Fretting is a failure mode in electrical connectors that have not been specifically designed to prevent it. Many connectors are keyed, with some mechanical component which prevents mating except with a correctly oriented matching connector, some connector housings are designed with locking mechanisms to prevent inadvertent disconnection or poor environmental sealing. Locking mechanism designs include locking levers of various sorts, screw locking, a terminal is a simple type of electrical connector that connects two or more wires to a single connection point. Wire nuts are another type of single point connector, terminal blocks provide a convenient means of connecting individual electrical wires without a splice or physically joining the ends. They are usually used to connect wiring among various items of equipment within an enclosure or to make connections among individually enclosed items. Since terminal blocks are available for a wide range of wire sizes and terminal quantity. One type of terminal block accepts wires that are prepared only by removing a short length of insulation from the end, another type accepts wires that have ring or spade terminal lugs crimped onto the wires. Printed circuit board mounted terminal blocks allow individual wires to be connected to the circuit board, a general type of connector that simply screws or clamps bare wire to a post, such connectors are frequently used in electronic test equipment and audio. Many, but not all binding posts will also accept a banana connector plug, since stripping the insulation from wires is time-consuming, many connectors intended for rapid assembly use insulation-displacement connectors so that insulation need not be removed from the wire
4.
Patch cable
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A patch cable or patch cord or patch lead is an electrical or optical cable used to connect one electronic or optical device to another for signal routing. Devices of different types are connected with patch cords, patch cords are usually produced in many different colors so as to be easily distinguishable, and are relatively short, perhaps no longer than two metres. However, patch cords typically refer only to short cords used with patch panels, patch cord cable differs from standard structured cabling cable in that patch cable is stranded for flexibility, whereas standard cable is solid copper. Because the patch cord is stranded copper construction the attenuation is higher on patch cords than solid cable so short lengths should be adhered to. Patch cords can be as short as 3 inches, to connect stacked components or route signals through a patch bay, as length increases, the cables are usually thicker and/or made with more shielding, to prevent signal loss and the introduction of unwanted radio frequencies and hum. Patch cords are made of coaxial cables, with the signal carried through a shielded core. Each end of the cable is attached to a connector so that the cord may be plugged in, connector types may vary widely, particularly with adapting cables. A pigtail is similar to a cord and is the informal name given to a cable fitted with a connector at one end. In the context of copper cabling, these cables are sometimes referred to as blunt patch cords, optical fiber pigtails, in contrast to copper pigtails, can be more accurately described as a connector than a cable or cord. A fiber pigtail is a single, short, usually tight-buffered, optical fiber that has an optical connector pre-installed on one end, the end of the fiber pigtail is stripped and fusion spliced to a single fiber of a multi-fiber trunk. Splicing of pigtails to each fiber in the trunk breaks out the cable into its component fibers for connection to the end equipment. A variety of cables are used to carry electrical signals in sound recording studios, microphones are typically connected to mixing boards or PA systems with XLR microphone cables which use three-pin XLR connectors. DJs using record players connect their turntables to mixers or PA systems with stereo RCA connectors, to resolve this problem, DJs can either use adapters or special cables. Heavier-gauge cables are used for carrying amplified signals from amplifiers to speakers, ¼ TRS phone connector cables can carry stereo signals, so they are used for stereo headphones and for some patching purposes. The patch bay is a panel of audio connectors where XLR cables. The cables could get tangled or mixed up, and it would be hard to know, when faced with 20 connectors at the end of the cable run, which cable was associated with which microphone or instrument. The patch bay is numbered, so that the engineer can note which microphone or instrument is plugged into each numbered connection, Cable management Crossover cable White Papers - Cable Anatomy
5.
Electronic test equipment
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Electronic test equipment is used to create signals and capture responses from electronic devices under test. In this way, the operation of the DUT can be proven or faults in the device can be traced. Use of electronic test equipment is essential to any work on electronics systems. ATE often includes many of instruments in real and simulated forms. Generally, more advanced test gear is necessary when developing circuits, designing a test system’s switching configuration requires an understanding of the signals to be switched and the tests to be performed, as well as the switching hardware form factors available. The following items are used for measurement of voltages, currents. Voltmeter Ohmmeter Ammeter, e. g. Galvanometer or Milliameter Multimeter e. g. VOM or DMM RLC Meter e. g and these systems are widely employed for incoming inspection, quality assurance, and production testing of electronic devices and subassemblies. The General Purpose Interface Bus is an IEEE-488 standard parallel interface used for attaching sensors, GPIB is a digital 8-bit parallel communications interface capable of achieving data transfers of more than 8 Mbytes/s. It allows daisy-chaining up to 14 instruments to a system using a 24-pin connector. It is one of the most common I/O interfaces present in instruments and is designed specifically for instrument control applications, the IEEE-488 specifications standardized this bus and defined its electrical, mechanical, and functional specifications, while also defining its basic software communication rules. GPIB works best for applications in industrial settings that require a connection for instrument control. The original GPIB standard was developed in the late 1960s by Hewlett-Packard to connect, the introduction of digital controllers and programmable test equipment created a need for a standard, high-speed interface for communication between instruments and controllers from various vendors. This standard was revised in 1978 and 1990. The IEEE488.2 specification includes the Standard Commands for Programmable Instrumentation, SCPI ensures compatibility and configurability among these instruments. The IEEE-488 bus has long been popular because it is simple to use and takes advantage of a selection of programmable instruments. Large systems, however, have the limitations, Driver fanout capacity limits the system to 14 devices plus a controller. Cable length limits the distance to two meters per device or 20 meters total, whichever is less. This imposes transmission problems on systems spread out in a room or on systems that require remote measurements, primary addresses limit the system to 30 devices with primary addresses
6.
Multimeter
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A multimeter or a multitester, also known as a VOM, is an electronic measuring instrument that combines several measurement functions in one unit. A typical multimeter can measure voltage, current, and resistance, analog multimeters use a microammeter with a moving pointer to display readings. Digital multimeters have a display, and may also show a graphical bar representing the measured value. Digital multimeters are now far more due to their cost and precision. A multimeter can be a device useful for basic fault finding and field service work. Multimeters are available in a range of features and prices. Cheap multimeters can cost less than US$10, while models with certified calibration can cost more than US$5,000. The first moving-pointer current-detecting device was the galvanometer in 1820 and these were used to measure resistance and voltage by using a Wheatstone bridge, and comparing the unknown quantity to a reference voltage or resistance. While useful in the lab, the devices were very slow and these galvanometers were bulky and delicate. The DArsonval/Weston meter movement uses a coil which carries a pointer. The coil rotates in a permanent magnetic field and is restrained by fine spiral springs which also serve to carry current into the moving coil and it gives proportional measurement rather than just detection, and deflection is independent of the orientation of the meter. Instead of balancing a bridge, values could be read off the instruments scale. The basic moving coil meter is only for direct current measurements. It is easily adapted to read heavier currents by using shunts or to voltage using series resistances known as multipliers. To read alternating currents or voltages, a rectifier is needed, multimeters were invented in the early 1920s as radio receivers and other vacuum tube electronic devices became more common. Macadie invented an instrument which could measure amperes, volts and ohms, the meter comprised a moving coil meter, voltage and precision resistors, and switches and sockets to select the range. The Automatic Coil Winder and Electrical Equipment Company was set up to manufacture the Avometer, although a shareholder of ACWEECO, Mr MacAdie continued to work for the Post Office until his retirement in 1933. His son, Hugh S. MacAdie, joined ACWEECO in 1927, Automatic Coil Winder and Electrical Equipment Company
7.
General Radio
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General Radio Company was a broad-line manufacturer of electronic test equipment. Started in Cambridge, Massachusetts in 1915 by Melville Eastham, the moved to West Concord in the 1950s. There, it became a player in the automatic test equipment business. It also produced lines of electrical component measuring equipment, sound and vibration measurement. Primarily because of its line of ATE equipment, the company was acquired by Teradyne in 2001 and has now been relocated to Teradynes corporate campus in North Reading. In 1991, QuadTech, Inc. was founded as spinoff of GenRads Instrumentation Division, IET Labs, Inc. purchased the GenRad product lines from QuadTech. in West Roxbury, MA
8.
Diameter
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In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle, both definitions are also valid for the diameter of a sphere. In more modern usage, the length of a diameter is called the diameter. In this sense one speaks of the rather than a diameter, because all diameters of a circle or sphere have the same length. Both quantities can be calculated efficiently using rotating calipers, for a curve of constant width such as the Reuleaux triangle, the width and diameter are the same because all such pairs of parallel tangent lines have the same distance. For an ellipse, the terminology is different. A diameter of an ellipse is any chord passing through the midpoint of the ellipse, for example, conjugate diameters have the property that a tangent line to the ellipse at the endpoint of one of them is parallel to the other one. The longest diameter is called the major axis, the word diameter is derived from Greek διάμετρος, diameter of a circle, from διά, across, through and μέτρον, measure. It is often abbreviated DIA, dia, d, or ⌀, the definitions given above are only valid for circles, spheres and convex shapes. However, they are cases of a more general definition that is valid for any kind of n-dimensional convex or non-convex object. The diameter of a subset of a space is the least upper bound of the set of all distances between pairs of points in the subset. So, if A is the subset, the diameter is sup, if the distance function d is viewed here as having codomain R, this implies that the diameter of the empty set equals −∞. Some authors prefer to treat the empty set as a case, assigning it a diameter equal to 0. For any solid object or set of scattered points in n-dimensional Euclidean space, in medical parlance concerning a lesion or in geology concerning a rock, the diameter of an object is the supremum of the set of all distances between pairs of points in the object. In differential geometry, the diameter is an important global Riemannian invariant, the symbol or variable for diameter, ⌀, is similar in size and design to ø, the Latin small letter o with stroke. In Unicode it is defined as U+2300 ⌀ Diameter sign, on an Apple Macintosh, the diameter symbol can be entered via the character palette, where it can be found in the Technical Symbols category. The character will not display correctly, however, since many fonts do not include it. In many situations the letter ø is a substitute, which in Unicode is U+00F8 ø
9.
Spring (device)
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A spring is an elastic object used to store mechanical energy. Springs are usually out of spring steel. There are a number of spring designs, in everyday usage the term often refers to coil springs. When a spring is compressed or stretched from its resting position, the rate or spring constant of a spring is the change in the force it exerts, divided by the change in deflection of the spring. That is, it is the gradient of the force versus deflection curve, an extension or compression springs rate is expressed in units of force divided by distance, for example lbf/in or N/m. A torsion spring is a spring that works by twisting, when it is twisted about its axis by an angle, a torsion springs rate is in units of torque divided by angle, such as N·m/rad or ft·lbf/degree. The inverse of spring rate is compliance, that is, if a spring has a rate of 10 N/mm, the stiffness of springs in parallel is additive, as is the compliance of springs in series. Springs are made from a variety of materials, the most common being spring steel. Small springs can be wound from pre-hardened stock, while larger ones are made from annealed steel, some non-ferrous metals are also used including phosphor bronze and titanium for parts requiring corrosion resistance and beryllium copper for springs carrying electrical current. Simple non-coiled springs were used throughout history, e. g. the bow. In the Bronze Age more sophisticated spring devices were used, as shown by the spread of tweezers in many cultures, coiled springs appeared early in the 15th century, in door locks. The first spring powered-clocks appeared in that century and evolved into the first large watches by the 16th century, in 1676 British physicist Robert Hooke discovered Hookes law which states that the force a spring exerts is proportional to its extension. Compression spring – is designed to operate with a compression load, flat spring – this type is made of a flat spring steel. Machined spring – this type of spring is manufactured by machining bar stock with a lathe and/or milling operation rather than a coiling operation, since it is machined, the spring may incorporate features in addition to the elastic element. Machined springs can be made in the load cases of compression/extension, torsion. Serpentine spring - a zig-zag of thick wire - often used in modern upholstery/furniture, the most common types of spring are, Cantilever spring – a spring which is fixed only at one end. Coil spring or helical spring – a spring is of two types, Tension or extension springs are designed to become longer under load and their turns are normally touching in the unloaded position, and they have a hook, eye or some other means of attachment at each end. Compression springs are designed to become shorter when loaded and their turns are not touching in the unloaded position, and they need no attachment points
10.
Banana
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The banana is an edible fruit – botanically a berry – produced by several kinds of large herbaceous flowering plants in the genus Musa. In some countries, bananas used for cooking may be called plantains, in contrast to dessert bananas. The fruit is variable in size, color and firmness, but is elongated and curved, with soft flesh rich in starch covered with a rind which may be green, yellow, red, purple. The fruits grow in clusters hanging from the top of the plant, almost all modern edible parthenocarpic bananas come from two wild species – Musa acuminata and Musa balbisiana. The scientific names of most cultivated bananas are Musa acuminata, Musa balbisiana, the old scientific name Musa sapientum is no longer used. Musa species are native to tropical Indomalaya and Australia, and are likely to have been first domesticated in Papua New Guinea. They are grown in 135 countries, primarily for their fruit, worldwide, there is no sharp distinction between bananas and plantains. Especially in the Americas and Europe, banana usually refers to soft, sweet, dessert bananas, particularly those of the Cavendish group, by contrast, Musa cultivars with firmer, starchier fruit are called plantains. In other regions, such as Southeast Asia, many kinds of banana are grown and eaten. The term banana is used as the common name for the plants which produce the fruit. This can extend to members of the genus Musa like the scarlet banana, pink banana. It can also refer to members of the genus Ensete, like the snow banana, both genera are classified under the banana family, Musaceae. The banana plant is the largest herbaceous flowering plant, all the above-ground parts of a banana plant grow from a structure usually called a corm. Plants are normally tall and fairly sturdy, and are mistaken for trees. Bananas grow in a variety of soils, as long as the soil is at least 60 cm deep, has good drainage and is not compacted. The leaves of plants are composed of a stalk and a blade. The base of the petiole widens to form a sheath, the tightly packed sheaths make up the pseudostem, the edges of the sheath meet when it is first produced, making it tubular. As new growth occurs in the centre of the pseudostem the edges are forced apart, cultivated banana plants vary in height depending on the variety and growing conditions
11.
Screw
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A screw is a type of fastener, sometimes similar to a bolt, typically made of metal, and characterized by a helical ridge, known as a male thread or just thread. A screw is an inclined plane wrapped around a nail, some screw threads are designed to mate with a complementary thread, known as a female thread, often in the form of a nut or an object that has the internal thread formed into it. Other screw threads are designed to cut a groove in a softer material as the screw is inserted. The most common uses of screws are to hold objects together, a screw will usually have a head on one end that contains a specially formed shape that allows it to be turned, or driven, with a tool. Common tools for driving screws include screwdrivers and wrenches, the head is usually larger than the body of the screw, which keeps the screw from being driven deeper than the length of the screw and to provide a bearing surface. The cylindrical portion of the screw from the underside of the head to the tip is known as the shank, the distance between each thread is called the pitch. Another rule is this, curl the fingers of right hand around the screw with your thumb pointing is the direction you want the screw to go. If the screw is right-handed and you turn the screw in the direction of your fingers the screw will move in the direction of your thumb, Screws with left-hand threads are used in exceptional cases. For example, when the screw will be subject to counterclockwise torque, the right side pedal of a bicycle has a left-hand thread. More generally, screw may mean any helical device, such as a clamp, a micrometer, there is no universally accepted distinction between a screw and a bolt. So, as a rule, when buying a packet of screws you would not expect nuts to be included. Part of the confusion over this is due to regional or dialectical differences. An externally threaded fastener which is prevented from being turned during assembly, an externally threaded fastener that has thread form which prohibits assembly with a nut having a straight thread of multiple pitch length is a screw. This distinction is consistent with ASME B18.2.1 and some dictionary definitions for screw, some of these issues are discussed below, ASME standards specify a variety of Machine Screws in diameters ranging up to 0.75 in. These fasteners are used with nuts but also often driven into tapped holes. They might be considered a screw or a bolt based on the Machinerys Handbook distinction, ASME standard B18.2. 1-1996 specifies Hex Cap Screws that range in size from 0. 25–3 in in diameter. These fasteners are very similar to hex bolts and they differ mostly in that they are manufactured to tighter tolerances than the corresponding bolts. Machinerys Handbook refers parenthetically to these fasteners as Finished Hex Bolts, in 1991 responding to an influx of counterfeit fasteners Congress passed PL 101-592 Fastener Quality Act This resulted in the rewriting of specifications by the ASME B18 committee
12.
Solder
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Solder is a fusible metal alloy used to create a permanent bond between metal workpieces. The word solder comes from the Middle English word soudur, via Old French solduree and soulder, from the Latin solidare, meaning to make solid. In fact, solder must be melted in order to adhere to and connect the pieces together, whenever possible, the solder should also be resistant to oxidative and corrosive effects that would degrade the joint over time. Solder that is intended for use in making connections between electronic components also usually has favorable electrical characteristics. Soft solder typically has a melting point range of 90 to 450 °C, and is used in electronics, plumbing. Manual soldering uses an iron or soldering gun. Alloys that melt between 180 and 190 °C are the most commonly used, soldering performed using alloys with a melting point above 450 °C is called hard soldering, silver soldering, or brazing. In specific proportions, some alloys can become eutectic — that is, non-eutectic alloys have markedly different solidus and liquidus temperatures, and within that range they exist as a paste of solid particles in a melt of the lower-melting phase. In electrical work, if the joint is disturbed in the pasty state before it has solidified totally, for electrical and electronics work, solder wire is available in a range of thicknesses for hand-soldering, and with cores containing flux. It is also available as a paste or as a preformed foil shaped to match the workpiece, alloys of lead and tin were commonly used in the past, and are still available, they are particularly convenient for hand-soldering. Lead-free solders have been increasing in use due to regulatory requirements plus the health and they are almost exclusively used today in consumer electronics. Plumbers often use bars of solder, much thicker than the used for electrical applications. Jewelers often use solder in thin sheets, which cut into snippets. In the US, manufacturers may receive tax benefits by reducing the use of lead-based solder, lead-free solders in commercial use may contain tin, copper, silver, bismuth, indium, zinc, antimony, and traces of other metals. Most lead-free replacements for conventional 60/40 and 63/37 Sn-Pb solder have melting points from 5 to 20 °C higher and it may be desirable to use minor modification of the solder pots used in wave-soldering, to reduce maintenance cost due to increased tin-scavenging of high-tin solder. Lead-free solder may be desirable for critical applications, such as aerospace and medical projects. Tin-Silver-Copper solders are used by two-thirds of Japanese manufacturers for reflow and wave soldering, tin-based solders readily dissolve gold, forming brittle intermetallics, for Sn-Pb alloys the critical concentration of gold to embrittle the joint is about 4%. Indium-rich solders are more suitable for soldering thicker gold layer as the rate of gold in indium is much slower
13.
Insulator (electricity)
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An electrical insulator is a material whose internal electric charges do not flow freely, very little electric current will flow through it under the influence of an electric field. This contrasts with other materials, semiconductors and conductors, which conduct electric current more easily, the property that distinguishes an insulator is its resistivity, insulators have higher resistivity than semiconductors or conductors. A perfect insulator does not exist, because even insulators contain small numbers of mobile charges which can carry current, in addition, all insulators become electrically conductive when a sufficiently large voltage is applied that the electric field tears electrons away from the atoms. This is known as the voltage of an insulator. Some materials such as glass, paper and Teflon, which have high resistivity, are good electrical insulators. Examples include rubber-like polymers and most plastics which can be thermoset or thermoplastic in nature, insulators are used in electrical equipment to support and separate electrical conductors without allowing current through themselves. An insulating material used in bulk to wrap electrical cables or other equipment is called insulation, the term insulator is also used more specifically to refer to insulating supports used to attach electric power distribution or transmission lines to utility poles and transmission towers. They support the weight of the suspended wires without allowing the current to flow through the tower to ground, electrical insulation is the absence of electrical conduction. Electronic band theory says that a charge flows if states are available into which electrons can be excited and this allows electrons to gain energy and thereby move through a conductor such as a metal. If no such states are available, the material is an insulator, most insulators have a large band gap. This occurs because the valence band containing the highest energy electrons is full, there is always some voltage that gives electrons enough energy to be excited into this band. Once this voltage is exceeded the material ceases being an insulator, however, it is usually accompanied by physical or chemical changes that permanently degrade the materials insulating properties. Materials that lack electron conduction are insulators if they lack other mobile charges as well, for example, if a liquid or gas contains ions, then the ions can be made to flow as an electric current, and the material is a conductor. Electrolytes and plasmas contain ions and act as conductors whether or not electron flow is involved, when subjected to a high enough voltage, insulators suffer from the phenomenon of electrical breakdown. These freed electrons and ions are in turn accelerated and strike other atoms, creating more charge carriers, rapidly the insulator becomes filled with mobile charge carriers, and its resistance drops to a low level. In a solid, the voltage is proportional to the band gap energy. The air in a region around a conductor can break down and ionise without a catastrophic increase in current. Even a vacuum can suffer a sort of breakdown, but in case the breakdown or vacuum arc involves charges ejected from the surface of metal electrodes rather than produced by the vacuum itself
14.
Color-coded
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A color code or colour code is a system for displaying information by using different colors. The earliest examples of color codes in use are for long distance communication by use of flags, the United Kingdom adopted a color code scheme for such communication wherein red signified danger and white signified safety, with other colors having similar assignments of meaning. The use of codes has been extended to abstractions, such as the Homeland Security Advisory System color code in the United States. Similarly, hospital emergency codes often incorporate colors, although they may also include numbers, color codes do present some potential problems. On forms and signage, the use of color can distract from black and white text
15.
Binding post
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A binding post is a connector commonly used on electronic test equipment to terminate a single wire or test lead. They are also found on loudspeakers and audio amplifiers as well as electrical equipment. A binding post contains a central threaded metal rod and a cap that screws down on that rod. The cap is commonly insulated with plastic and color-coded, red commonly means an active or positive terminal, black indicates an inactive or negative terminal, bare wire inserted through the same hole and clamped, or Wrapped around the metal post and clamped. A lug terminal, with a 1/4-inch inner diameter, inserted around the metal post, the binding post was a commercial invention of the General Radio Corporation. Even so-called isolated binding posts are not sufficiently isolated to protect users from coming into contact with their metal parts carrying voltage. As such they are not suitable to be used for carrying dangerous voltages, on several types of equipment it has been becoming common to no longer use the traditional binding posts, but safety banana jacks. The universal property of binding posts is lost here, since safety banana jacks can only be used with traditional and safety banana plugs. But this also impaired safety as two wires or pin connectors could be inserted from opposite sides of two binding posts and the tips of the wires or probes might inadvertently short together, holes are now normally aligned in such a fashion that such shorts cannot occur. In order to permit the use of double banana plugs, the distance between the positive and negative plugs should be 3/4 inch, fahnestock clip — an earlier device, now largely supplanted by binding posts Banana connector About. com glossary definition
16.
BNC connector
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The BNC connector is a miniature quick connect/disconnect radio frequency connector used for coaxial cable. It features two bayonet lugs on the connector, mating is fully achieved with a quarter turn of the coupling nut. BNC connectors are used with coaxial cable in radio, television, and other radio-frequency electronic equipment, test instruments. The BNC was commonly used for computer networks, including ARCnet, the IBM PC Network. BNC connectors are made to match the impedance of cable at either 50 ohms or 75 ohms. They are usually applied for frequencies below 4 GHz and voltages below 500 volts, similar connectors using the bayonet connection principle exist, and a threaded connector is also available. The BNC was originally designed for use and has gained wide acceptance in video. The BNC uses a slotted outer conductor and some plastic dielectric on each gender connector and this dielectric causes increasing losses at higher frequencies. Above 4 GHz, the slots may radiate signals, so the connector is usable, both 50 ohm and 75 ohm versions are available. The BNC connector is used for signal connections such as, analog, the BNC connector is used for composite video on commercial video devices. Consumer electronics devices with RCA connector jacks can be used with BNC-only commercial video equipment by inserting an adapter, BNC connectors were commonly used on 10base2 thin Ethernet network cables and network cards. BNC connections can also be found in recording studios, digital recording equipment uses the connection for synchronization of various components via the transmission of word clock timing signals. Typically the male connector is fitted to a cable, and the female to a panel on equipment, cable connectors are often designed to be fitted by crimping using a special power or manual tool. Wire strippers which strip outer jacket, shield braid, and inner dielectric to the lengths in one operation are used. The connector was named the BNC after its bayonet mount locking mechanism and its inventors, Paul Neill, Neill worked at Bell Labs and also invented the N connector, Concelman worked at Amphenol and also invented the C connector. A backronym has been applied to it, British Naval Connector. Another common incorrectly attributed origin is Berkeley Nucleonics Corporation, the basis for the development of the BNC connector was largely the work of Octavio M. Salati, a graduate of the Moore School of Electrical Engineering of the University of Pennsylvania. In 1945, while working at Hazeltine Electronics Corporation, he filed a patent for a connector for coaxial cables that would minimize wave reflection/loss, the patent was granted in 1951
17.
Coaxial cable
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Coaxial cable, or coax, is a type of cable that has an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield. Many coaxial cables also have an outer sheath or jacket. The term coaxial comes from the conductor and the outer shield sharing a geometric axis. Coaxial cable was invented by English engineer and mathematician Oliver Heaviside, Coaxial cable is used as a transmission line for radio frequency signals. Its applications include feedlines connecting radio transmitters and receivers with their antennas, computer network connections, digital audio and this allows coaxial cable runs to be installed next to metal objects such as gutters without the power losses that occur in other types of transmission lines. Coaxial cable also provides protection of the signal from external electromagnetic interference, the cable is protected by an outer insulating jacket. Normally, the shield is kept at ground potential and a signal carrying voltage is applied to the center conductor, the advantage of coaxial design is that electric and magnetic fields are restricted to the dielectric with little leakage outside the shield. Conversely, electric and magnetic fields outside the cable are largely kept from interfering with signals inside the cable, larger diameter cables and cables with multiple shields have less leakage. Common applications of coaxial cable include video and CATV distribution, RF and microwave transmission, the characteristic impedance of the cable is determined by the dielectric constant of the inner insulator and the radii of the inner and outer conductors. A controlled cable characteristic impedance is important because the source and load impedance should be matched to ensure maximum power transfer, other important properties of coaxial cable include attenuation as a function of frequency, voltage handling capability, and shield quality. Coaxial cable design choices affect physical size, frequency performance, attenuation, power handling capabilities, flexibility, strength, the inner conductor might be solid or stranded, stranded is more flexible. To get better performance, the inner conductor may be silver-plated. Copper-plated steel wire is used as an inner conductor for cable used in the cable TV industry. The insulator surrounding the conductor may be solid plastic, a foam plastic. The properties of control some electrical properties of the cable. A common choice is a solid polyethylene insulator, used in lower-loss cables, solid Teflon is also used as an insulator. Some coaxial lines use air and have spacers to keep the conductor from touching the shield. Many conventional coaxial cables use braided copper wire forming the shield and this allows the cable to be flexible, but it also means there are gaps in the shield layer, and the inner dimension of the shield varies slightly because the braid cannot be flat
18.
Plugboard
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A plugboard, or control panel, is an array of jacks, or sockets, into which patch cords can be inserted to complete an electrical circuit. Control panels were used to direct the operation of unit record equipment. Plugboards were used on some machines, and some early computers. The earliest machines were hard wired for specific applications, Control panels were introduced in 1906 for the Hollerith Type 1 Tabulator. Removable control panels were introduced with the Hollerith type 3-S tabulator in the 1920s, applications then could be wired on separate control panels, and inserted into tabulators as needed. Removable control panels came to be used in all unit record machines where the use for different applications required rewiring. IBM removable control panels ranged in size from 6 1/4 by 10 3/4 to roughly one to two feet on a side and had an array of hubs. For example, in a card duplicator application a card column reading hub might be connected to a punch magnet entry hub and it was a relatively simple matter to copy some fields, perhaps to different columns, and ignore other columns by suitable wiring. Tabulator control panels could require dozens of patch cords for some applications, Tabulator functions were implemented with both mechanical and electrical components. Control panels simplified the changing of electrical connections for different applications, for most machines with control panels, from collators, interpreters, to the IBM407, IBM manuals describe the control panel as directing or automatic operation was obtained by. The control panels of calculators, such as the IBM602 and IBM604, unit record equipment was typically configured for a specific task using a removable control panel. Perhaps the closest modern analog is the gate array, where a fixed number of logic components are made available. Wiring a unit record control panel required knowledge of the machines components, the components of most unit record machines were synchronized to a rotating shaft. One rotation represented a single cycle, during which punched cards would advance from one station to the next, a line might be printed. The cycles were divided into points according to when the rows on a card would appear under a read or punch station. On most machines, cards were fed face down, 9-edge first, thus the first point in a card cycle would 9-time, the second 8 time and so on to 0-time. The times from 9 to 0 were known as digits and these would be followed by 11 time and 12 time, also known as zones. In a read station, a set of 80 spring wire brushes pressed against the card, each brush was connected to an individual hub on the control panel, from which it could be wired to another hub, as needed
19.
Split pin
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A split pin, also known in the United States as a cotter pin or cotter key, is a metal fastener with two tines that are bent during installation, similar to a staple or rivet. Typically made of wire with a half-circular cross section, split pins come in multiple sizes and types. The British definition of cotter pin is equivalent to U. S. term cotter, there are signs that manufacturers and stockists are increasingly listing both names together to avoid confusion, this led to the term split cotter sometimes being used for a split pin. A new split pin has its flat inner surfaces touching for most of its length so that it appears to be a split cylinder, once inserted, the two ends of the pin are bent apart, locking it in place. When they are removed they are supposed to be discarded and replaced, split pins are typically made of soft metal, making them easy to install and remove, but also making it inadvisable to use them to resist strong shear forces. Common materials include steel, brass, bronze, stainless steel. As shown above, there are different types of ends available on split pins, the most common is the extended prong with a square cut, but extended prongs are available with all of the other types of ends. The extended prong type is popular because it makes it easier to separate the tines, to ease insertion into a hole the longer tine may be slightly curved to overlap the tip of the shorter tine or it is beveled. The length, L, of the pin is defined as the distance from the end of the shortest tine to the point of the eyelet that contacts the hole. Hammer lock split pins are installed by striking the head with a hammer to secure the pin. This forces the shorter tine forward, spreading the pin, standard Humped Clinch The diameter of split pins are standardized. American split pins start at 1⁄32 in and end at 3⁄4 in, split pins are frequently used to secure other fasteners, e. g. clevis pins, as well as being used in combination with hardboard discs as a traditional joining technique for teddy bears. A common application of this is used to secure a castellated nut. Split pins may be used in applications as low-tech shear pins. Coiled spring pins Linchpin R-clip Bibliography
20.
Screw thread
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A screw thread, often shortened to thread, is a helical structure used to convert between rotational and linear movement or force. A screw thread is a ridge wrapped around a cylinder or cone in the form of a helix, with the former being called a straight thread, a screw thread is the essential feature of the screw as a simple machine and also as a fastener. The mechanical advantage of a screw depends on its lead. This characteristic is essential to the vast majority of its uses, the tightening of a fasteners screw thread is comparable to driving a wedge into a gap until it sticks fast through friction and slight elastic deformation. Screw threads have several applications, Fastening, Fasteners such as screws, machine screws, nuts. Connecting threaded pipes and hoses to each other and to caps, gear reduction via worm drives Moving objects linearly by converting rotary motion to linear motion, as in the leadscrew of a jack. Measuring by correlating linear motion to rotary motion, as in a micrometer, both moving objects linearly and simultaneously measuring the movement, combining the two aforementioned functions, as in a leadscrew of a lathe. In all of these applications, the thread has two main functions, It converts rotary motion into linear motion. It prevents linear motion without the corresponding rotation, every matched pair of threads, external and internal, can be described as male and female. For example, a screw has male threads, while its matching hole has female threads, the helix of a thread can twist in two possible directions, which is known as handedness. This is known as a thread, because it follows the right hand grip rule. Threads oriented in the direction are known as left-handed. By common convention, right-handedness is the default handedness for screw threads, therefore, most threaded parts and fasteners have right-handed threads. Left-handed thread applications include, Where the rotation of a shaft would cause a conventional right-handed nut to loosen rather than to tighten due to fretting induced precession, examples include, The left hand pedal on a bicycle. The left-hand grinding wheel on a bench grinder, the lug nuts on the left side of some automobiles. The securing nut on some circular saw blades - the large torque at startup should tend to tighten the nut. The spindle on brushcutter and line trimmer heads, so that the torque tends to tighten rather than loosen the connection In combination with right-hand threads in turnbuckles, in such a case, the coupling will have one right-handed and one left-handed thread. In some instances, for example early ballpoint pens, to provide a method of disassembly
21.
Hameg
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HAMEG Instruments GmbH is a German enterprise specialized in the development and production of laboratory instruments. The company is located in Mainhausen near Frankfurt, Germany and owned by Rohde & Schwarz, the business was established in 1957 by Karl Hartmann in Frankfurt/Main under the name HAMEG KG. The company name is derived from Hartmann-Messgeräte, the first product was a 5 MHz one channel oscilloscope. In 2005, the founder retired and the business was acquired by the electronics company Rohde & Schwarz with headquarters in Munich. During that time, the name was changed to HAMEG Instruments GmbH, HAMEG maintained subsidiaries in Chemnitz and Münchenbernsdorf as well as a distribution subsidiary in France. At the end of 2010, HAMEG abandoned the manufacturing locations Mainhausen and Münchenbernsdorf, in the wake of this transition, approximately 80 jobs were cut at HAMEG. Other company divisions such as development, product management, sales, customer service, at the end of 2011, Rohde & Schwarz announced that the company would offer the entire HAMEG product portfolio through its own European distribution network. Only a few later, in February 2012, HAMEG launched a new product logo. This was the first time that the HAMEG affiliation with Rohde & Schwarz became visible on HAMEG products thanks to the name label. As of March 2013, HAMEG products have made available virtually all over the world through the Rohde & Schwarz distribution network. In June 2014 Rohde & Schwarz announced that in the all new products from HAMEG will be marketed under the name Rohde & Schwarz. The company primarily serves the entry-level segment of the market and is used at electronics laboratories, production supervision as well as at schools. For a very time, HAMEG was convinced of the benefits of analog technology in the context of the oscilloscope market. In 2004, when HAMEG introduced a new series of so-called CombiScopes, in 2007, HAMEG produced the HM2008 oscilloscope which includes an analog and a digital element as well as mixed-signal functions. In late 2008, HAMEG introduced the first purely digital oscilloscope with TFT monitor at the electronica electronics trade fair in Munich, as all subsequently introduced instruments, these oscilloscopes include mixed-signal functions and the option to decode serial buses such as I2C, SPI, CAN and LIN. For instruments with TFT monitors, HAMEG skipped the generation of the classical. By 2012, HAMEG had developed a range of 11 MSO instruments. In autumn of 2012, HAMEG announced intentions to discontinue production of analog oscilloscopes
22.
Short circuit
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A short circuit is an electrical circuit that allows a current to travel along an unintended path with no or a very low electrical impedance. The electrical opposite of a circuit is an open circuit. It is common to misuse short circuit to describe any electrical malfunction, a short circuit is an abnormal connection between two nodes of an electric circuit intended to be at different voltages. This results in an electric current limited only by the Thévenin equivalent resistance of the rest of the network and potentially causes circuit damage, overheating. Although usually the result of a fault, there are cases where short circuits are caused intentionally, for example, in circuit analysis, a short circuit is a connection between two nodes that forces them to be at the same voltage. In an ideal circuit, this means there is no resistance. In real circuits, the result is a connection with almost no resistance, in such a case, the current is limited by the rest of the circuit. A common type of short circuit occurs when the positive and negative terminals of a battery are connected with a low-resistance conductor, with low resistance in the connection, a high current exists, causing the cell to deliver a large amount of energy in a short time. Overloaded wires can also overheat, sometimes causing damage to the wires insulation, in mains circuits, short circuits may occur between two phases, between a phase and neutral or between a phase and earth. Such short circuits are likely to result in a high current. However, it is possible for circuits to arise between neutral and earth conductors, and between two conductors of the same phase. Such short circuits can be dangerous, particularly as they may not immediately result in a current and are therefore less likely to be detected. Possible effects include unexpected energisation of a circuit presumed to be isolated, to help reduce the negative effects of short circuits, power distribution transformers are deliberately designed to have a certain amount of leakage reactance. The leakage reactance helps limit both the magnitude and rate of rise of the fault current, a short circuit may lead to formation of an electric arc. The arc, a channel of hot ionized plasma, is highly conductive, surface erosion is a typical sign of electric arc damage. Even short arcs can remove significant amount of materials from the electrodes, a short circuit fault current can, within milliseconds, be thousands of times larger than the normal operating current of the system. Damage from short circuits can be reduced or prevented by employing fuses, circuit breakers, or other overload protection, overload protection must be chosen according to the current rating of the circuit. Circuits for large home appliances require protective devices set or rated for higher currents than lighting circuits, wire gauges specified in building and electrical codes are chosen to ensure safe operation in conjunction with the overload protection
23.
Test probe
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A test probe is a physical device used to connect test equipment to a device under test. Test probes range from simple, robust devices to complex probes that are sophisticated, expensive. Specific types include test prods, oscilloscope probes and current probes, a test probe is often supplied as a test lead, which includes the probe, cable and terminating connector. Voltage probes are used to measure voltages present on the DUT, to achieve high accuracy, the test instrument and its probe must not significantly affect the voltage being measured. This is accomplished by ensuring that the combination of instrument and probe exhibit a high impedance that will not load the DUT. For AC measurements, the component of impedance may be more important than the resistive. The handle allows a person to hold and guide the probe without influencing the measurement or being exposed to dangerous voltages that might cause electric shock, within the probe body, the wire is connected to a rigid, pointed metal tip that contacts the DUT. Some probes allow an alligator clip to be attached to the tip, test leads are usually made with finely stranded wire to keep them flexible, of wire gauges sufficient to conduct a few amperes of electric current. The insulation is chosen to be flexible and have a breakdown voltage higher than the voltmeters maximum input voltage. The many fine strands and the thick insulation make the wire thicker than ordinary hookup wire, two probes are used together to measure voltage, current, and two-terminal components such as resistors and capacitors. When making DC measurements it is necessary to know which probe is positive, depending upon the accuracy required, they can be used with signal frequencies ranging from DC to a few kilohertz. When sensitive measurements must be made shields, guards, and techniques such as four-terminal Kelvin sensing are used, tweezer probes are a pair of simple probes fixed to a tweezer mechanism, operated with one hand, for measuring voltages or other electronic circuit parameters between closely spaced pins. Spring probes are spring-loaded pins used in electrical test fixtures to contact test points, component leads, oscilloscopes display the instantaneous waveform of varying electrical quantities, unlike other instruments which give numerical values of relatively stable quantities. Scope probes fall into two categories, passive and active. Passive scope probes contain no active parts, such as transistors. Because of the high frequencies often involved, oscilloscopes do not normally use simple wires to connect to the DUT, flying leads are likely to pick up interference, so they are not suitable for low-level signals. Furthermore, the inductance of flying leads make them unsuitable for high frequency signals, instead, a specific scope probe is used, which uses a coaxial cable to transmit the signal from the tip of the probe to the oscilloscope. Although coaxial cable has lower inductance than flying leads, it has higher capacitance, consequently, a one-meter high-impedance direct coaxial probe may load the circuit with a capacitance of about 110 pF and a resistance of 1 megohm
24.
Audio and video interfaces and connectors
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Audio connectors and video connectors are electrical connectors - plugs and sockets - for carrying audio signal and video signal. Audio interfaces and video interfaces define physical parameters and interpretation of signals, for digital audio and digital video, this can be thought of as defining the physical layer, data link layer, and most or all of the application layer. For analog audio and analog video these functions are all represented in a single signal specification like NTSC or the direct speaker-driving signal of analog audio. Physical characteristics of the electrical or optical equipment includes the types and numbers of wires required, voltages, frequencies, optical intensity, any data link layer details define how application data is encapsulated. In some cases, the layer is left open, for example. This means that in cases not all components with physically compatible connectors will actually work together. Analog A/V connectors often use shielded cables to inhibit radio frequency interference, for efficiency and simplicity, the same codec or signal convention is used by the storage medium. For example, VHS tapes can store a magnetic representation of an NTSC signal, and the specification for Bluray discs incorporates PCM, MPEG-2, and DTS. Some playback devices can re-encode audio or video so that the used for storage does not have to be the same as the format transmitted over the A/V interface. Some connectors can carry both audio and video simultaneously, HDMI combines DVI-compliant uncompressed video data with compressed or uncompressed audio. Note that there are no differences in the signals transmitted over optical or coaxial S/PDIF connectors—both carry exactly the same information, selection of one over the other rests mainly on the availability of appropriate connectors on the chosen equipment and the preference and convenience of the user. Connections longer than 6 meters or so, or those requiring tight bends, should use coaxial cable, high-Definition Multimedia Interface is a compact audio/video standard for transmitting uncompressed digital data. There are three HDMI connector types, Type A and Type B were defined by the HDMI1.0 specification. Type C was defined by the HDMI1.3 specification, Type A is electrically compatible with single link DVI-D. Type B is electrically compatible with dual link DVI-D but has not yet used in any products. IEEE1394 FireWire is a data transfer protocol commonly used for digital cameras. In the United States, cable TV converter set top boxes by law also have the connection for transferring content directly to a TV or computer for viewing,1394 can also use coaxial cable as a medium for longer runs. Unlike Point-to-Point connections listed above, IEEE1394 is able to host several signals on the wire, with the data delivered
25.
DIN connector
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A DIN connector is an electrical connector that was originally standardized in the early 1970s by the Deutsches Institut für Normung, the German national standards organization. Some of these connectors have also used in analog video applications, for power connections. The original DIN standards for these connectors are no longer in print and have been replaced with the equivalent international standard IEC 60130-9, while DIN connectors appear superficially similar to the newer professional XLR connectors, they are not compatible. All male connectors of this family of connectors feature a 13.2 mm diameter metal shield with a notch that limits the orientation in which plug, the pins are 1.45 mm in diameter and equally spaced in a 7.0 mm diameter circle. The skirt is keyed to ensure that the plug is inserted with the correct orientation, the basic design also ensures that the shielding is connected between socket and plug prior to any signal path connection being made. There are seven common patterns, with any number of pins from three to eight, three different five-pin connectors exist, known as 180°, 240°, and 270° after the angle of the arc swept between the first and last pin. There are also two variations of the six-pin, seven-pin and eight-pin connectors, one where the pins form 360°. 3-pin and 180° 5-pin connectors will also fit the 270° 7-pin, in addition to these connectors, there are also connectors with 10,12 and 14 pins. Screw-locking versions of this connector have also used in instrumentation, process control. In North America this variant is called a small Tuchel connector after one of the major manufacturers. Tuchel is now a division of Amphenol, the pin and socket inserts are nearly identical to those used in non-locking connectors, and in some cases locking and non-locking connectors can be mated. Additional configurations up to 24 pins are also offered in the shell size. In addition to this, the pin of such a connector are inverted with respect to DIN standards. Some manufacturers offered panel-mounted jacks with potential-free auxiliary contacts that would open if a plug were inserted, a polarised two-pin unshielded connector, designed for connecting a loudspeaker to a power amplifier, is known as the DIN41529 loudspeaker connector. It exists as a female version, and line-mounted male and female versions. The male version has a central pin, and circular pin mounted off-centre. The circular pin is connected to the line while the spade is connected to the negative line. The panel-mounting female version is available with or without an auxiliary contact that disconnects the internal speaker of the if a external speaker connector is inserted
26.
Mini-DIN connector
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The mini-DIN connectors are a family of multi-pin electrical connectors used in a variety of applications. Mini-DIN is similar to the larger, older DIN connector, both are standards of the Deutsches Institut für Normung, the German standards body. Mini-DIN connectors are 9.5 mm in diameter and come in seven patterns, each pattern is keyed in such a way that a plug with one pattern cannot be mated with any socket of another pattern. The pin numbering for the plugs shown above is done left to right, pin 1 will be on the lower left, and the highest pin number will be on the upper right. Some notable examples of standard mini-DIN connectors include, Mini-DIN-3 connectors were used in implementations of Apple LocalTalk. Mini-DIN-4 connectors are used for S-video, and were used for Apple Desktop Bus, mini-DIN-6 connectors were used for IBM PC compatible PS/2 keyboard and mouse ports and for Acorn Archimedes keyboards. Mini-DIN-8 connectors were used for Sun Microsystems keyboard and mouse ports, as well as for serial printer, modem, Mini-DIN-9 connectors were used for Acorn Archimedes Quadrature Mice and Microsoft InPort Bus Mice. Mini-DIN-7 and Mini-DIN-9 connectors have used for a variety of audio. Also, iRobot Roomba Vacuum cleaning robots use a Mini-DIN-7 to expose an interface for custom sensing, mini-DIN-6 and Mini-DIN-8 connectors are frequently used in ham radio applications to interface with computers for data packet communications and radio programming. Several non-standard sockets are designed to mate with standard mini-DIN plugs and these connectors provide extra conductors, and are used to save space by combining functions in one connector that would otherwise require two standard connectors. Other non-standard connectors mate only with their matching connectors, and are mini-DIN connectors only in the sense of sharing the 9.5 mm plug body. These mini-DIN style plugs are not approved by the Deutsches Institut für Normung, the German standards body, and many applications could be considered proprietary
27.
Phone connector (audio)
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A phone connector, also known as phone jack, audio jack, headphone jack or jack plug, is a common family of electrical connector typically used for analog signals, primarily audio. It is cylindrical in shape, typically two, three, four and, recently, five contacts. Three-contact versions are known as TRS connectors, where T stands for tip, R stands for ring, similarly, two-, four- and five- contact versions are called TS, TRRS and TRRRS connectors respectively. The phone connector was invented for use in telephone switchboards in the 19th century and is widely used. In its original configuration, the diameter of the sleeve conductor is 1⁄4 inch. The mini connector has a diameter of 3.5 mm, specific models are termed stereo plug, mini-stereo, mini jack, headphone jack and microphone jack, or are referred to by size, i. e.3. 5mm or 6. 35mm. In the UK, the terms jack plug and jack socket are commonly used for the male and female phone connectors. In the US, an electrical connector is called a jack. Phone plugs and jacks are not to be confused with the similar terms phono plug and phono jack which refer to RCA connectors common in consumer hi-fi, the 3.5 mm connector is, however, sometimes—but counter to the connector manufacturers nomenclature—referred to as mini phono. Modern phone connectors are available in three standard sizes, the original 1⁄4 in version dates from 1878, when it was used for manual telephone exchanges, making it the oldest electrical connector standard still in use. The 3.5 mm or miniature and 2.5 mm or sub-miniature sizes were originally designed as two-conductor connectors for earpieces on transistor radios since the 1950s, the standard still used today. The 3.5 mm connector, which is the most commonly used in application today, was popularized by the Sony EFM-117J radio which was released in 1964. It became very popular with its application on the Walkman in 1979, the 3.5 mm and 2.5 mm sizes are sometimes referred to as 1⁄8 in and 3⁄32 in respectively in the United States, though those dimensions are only approximations. All three sizes are now available in two-conductor and three-conductor versions. Four- and five-conductor versions of the 3.5 mm plug are used for certain applications, a four-conductor version is often used in compact camcorders and portable media players, and sometimes also in laptop computers and smartphones, providing stereo sound plus a video signal. Proprietary interfaces using both four- and five-conductor versions exist, where the conductors are used to supply power for accessories. The four-conductor 3.5 mm plug is used as a connector on handheld amateur radio transceivers from Yaesu. It is also used in some amps like the LH Labs Geek Out V2+ for a balanced output, the most common arrangement remains to have the male plug on the cable and the female socket mounted in a piece of equipment, the original intention of the design
28.
RCA connector
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An RCA connector, sometimes called a phono connector or Cinch connector, is a type of electrical connector commonly used to carry audio and video signals. The connectors are sometimes casually referred to as A/V jacks. The name RCA derives from the Radio Corporation of America, which introduced the design by the early 1940s for internal connection of the pickup to the chassis in home radio-phonograph consoles. It was originally a low-cost, simple design, intended only for mating, refinement came with later designs, although they remained compatible. However, quarter-inch phone connectors are common in professional audio. The connections plug is called an RCA plug or phono plug, the name phono plug is sometimes confused with a phone plug which may refer to a quarter-inch phone plug – Tip/Sleeve or Tip/Ring/Sleeve connector – or to a 4P4C connector used for a telephone. In the most normal use, cables have a plug on each end, consisting of a central male connector. The ring is often segmented for flexibility, devices mount the socket, consisting of a central hole with a ring of metal around it. The ring is smaller in diameter and longer than the ring on the plug. The jack has an area between the outer and inner rings which is filled with an insulator, typically plastic. Its use as a connector for video signals is extremely common. RCA connectors and cable are commonly used to carry S/PDIF-formatted digital audio. Connections are made by pushing the cables plug into the jack on the device. Continuous noise can occur if the plug partially falls out of the jack, breaking ground connection, some variants of the plug, especially cheaper versions, also give very poor grip and contact between the ground sheaths due to their lack of flexibility. They are often color-coded, yellow for composite video, red for the audio channel. This trio of jacks can be found on the back of almost all audio, one or more sets are often found on TV sets to facilitate connection of camcorders, other portable video sources and video game consoles. Varying cable quality means that a cheap line-level audio cable might not successfully transfer component video, cables should meet the S/PDIF specification as defined by the international standard IEC 60958-3 for assured performance. The male plug has a pin which is 3.175 mm in diameter
29.
Speaker terminal
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A speaker terminal is a type of electrical connector often used for connecting audio equipment to speakers or amplifiers. The terminals are used in pairs with each of the cables two wires being connected to one terminal in the pair. Since speaker cables are polarized, the terminals are most often color-coded so that the wire connects to the red. The terminal consists of a spring-loaded metallic pincher which opens when the level is pressed, and this terminal may be used with a variety of wire gauges as well as with either solid core or stranded wires. DIY projects sometimes reuse speaker terminals for other applications using bare wire leads, speaker wire Banana connector Binding post
30.
Speakon connector
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The Speakon is a type of cable connector, originally manufactured by Neutrik, mostly used in professional audio systems for connecting loudspeakers to amplifiers. The name Speakon is a registered trademark, other manufacturers make compatible products, often under the name speaker twist connector. Speakon connectors are rated for 40 A RMS continuous current, higher than 1/4-inch TS phone connectors, two-pole twist lock, compared to standard phone plugs, Speakon connectors also have the following advantages, No possible confusion with low-current XLR microphone cables or 1/4 instrument cables. They lock into their sockets with a motion, making them significantly less prone to disconnection than standard phone plugs. They are shielded from human touch, preventing electrical shock from a high-powered amplifier, the contacts do not short out during connection or disconnection. This can be a benefit when working with sound equipment that is in operation, the chassis receptacles are airtight, so do not provide an air leak path from speaker enclosures. A Speakon connector is designed with a system that may be designed for soldered or screw-type connections. Line connectors mate with panel connectors and typically a cable will have identical connectors at both ends, if it is needed to join cables, a coupler can be used. With 1/4 speaker jacks and XLR connections, it is possible for users to erroneously use low-current shielded microphone or instrument cables in a high-current speaker application, Speakon cables are intended solely for use in high current audio applications. Speakon connectors arrange their contacts in two rings, with the inner contacts named +1, +2, etc. and the outer contacts connectors. The phase convention is that positive voltage on the + contact causes air to be pushed away from the speaker, Speakon connectors are made in two, four and eight-pole configurations. The two-pole line connector will mate with the four-pole panel connector, connecting to +1 and −1, the eight-pole connector is physically larger to accommodate the extra poles. The four-pole connector is the most common at least from the availability of ready-made leads, similarly, the eight-pole connector could be used for tri-amping, or quad-amping. The combiner and splitter Y-leads are the same, two connectors on one end, connected to the ±1 and ±2 pins, respectively. Some amplifiers and mixer-amplifiers are configured to do this without the need for a combiner, also available are 2-pole combo receptacles that can also accept 4-pole cables and 1/4″ phone plugs
31.
XLR connector
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The XLR connector is a style of electrical connector, primarily found on professional audio, video, and stage lighting equipment. The connectors are circular in design and have between 3 and 7 pins and they are most commonly associated with balanced audio interconnection, including AES3 digital audio, but are also used for lighting control, low-voltage power supplies, and other applications. XLR connectors are available from a number of manufacturers and are covered by a standard for dimensions. They are superficially similar to the older and smaller DIN connector range, a smaller version, the Mini XLR Connector, is used on smaller equipment. The XLR connector was invented by James H, there was also an XLP series which used a hard plastic insulation, but was otherwise the same. ITT Cannon originally manufactured XLR connectors in two locations Kanagawa, Japan and Melbourne, Australia, the Australian operation was sold to Alcatel Components in 1992 and then acquired by Amphenol in 1998. ITT Cannon continues to manufacture XLR connectors in Japan, the Switchcraft corporation later started manufacturing compatible connectors, followed by Neutrik. These improvements have made Neutrik the most popular brand of XLR connector, unbranded XLRs are also made by East Asian manufacturers. Originally these were copies of the Cannon or Switchcraft designs, XLR connectors are available in male and female versions in both cable and chassis mounting designs, a total of four styles. This is slightly unusual as many other connector designs omit one of the styles, the female XLR connectors are designed to first connect pin 1, before the other pins make contact, when a male XLR connector is inserted. With the ground connection established before the lines are connected. As of 2016, XLR connectors are available with up to 10 pins, XLR connectors from different manufacturers will intermate, with the exception of Switchcraft six-pin models, which use a non-standard arrangement for the pins. Three-pin XLR connectors are by far the most common style, and are a standard for balanced audio signals. The great majority of microphones use the XLR connector. In previous years, they were used for connections, for instance by Trace Elliot in its bass enclosures. The XLR could accept 14 AWG wire with a capacity of 15 amps, suitable for most loudspeakers. The Speakon connector accepts larger wire and carries current, and it provides a better shield for the contacts. Three-pin XLR connectors are used to interconnect powered speakers with line-level signals and this use is commonly seen in PA system applications and seems to be growing more common
32.
S/PDIF
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S/PDIF is a type of digital audio interconnect used in consumer audio equipment to output audio over reasonably short distances. The signal is transmitted over either a cable with RCA connectors or a fibre optic cable with TOSLINK connectors. S/PDIF interconnects components in home theatres and other digital high-fidelity systems, S/PDIF is based on the AES3 interconnect standard. S/PDIF is a link layer protocol as well a set of physical layer specifications for carrying digital audio signals between devices and components over either optical or electrical cable. The name stands for Sony/Philips Digital Interconnect Format but is known as Sony/Philips Digital Interface. Sony and Philips were the designers of S/PDIF. S/PDIF is standardized in IEC60958 as IEC60958 type II, a common use for the S/PDIF interface is to carry compressed digital audio for surround sound as defined by the standard IEC61937. This mode is used to connect the output of a DVD player or computer, via optical or coax, another common use is to carry two channels of uncompressed digital audio from a CD player to an amplifying receiver. S/PDIF was developed at the time as the main standard, AES3. The RCA connectors are typically colour-coded orange to differentiate from other RCA connector uses such as composite video, the cable was also changed from 110 Ω balanced twisted pair to 75 Ω coaxial cable, using RCA jacks. Signals transmitted over consumer-grade TOSLINK connections are identical in content to those transmitted over coaxial connectors, though TOSLINK S/PDIF commonly exhibits higher jitter. S/PDIF is used to digital signals of a number of formats, the most common being the 48 kHz sample rate format. In order to both systems, as well as others that might be needed, the format has no defined data rate. Instead, the data is sent using biphase mark code, which has one or two transitions for every bit, allowing the original word clock to be extracted from the signal itself. S/PDIF is meant to be used for transmitting 20-bit audio data streams plus other related information, to transmit sources with less than 20 bits of sample accuracy, the superfluous bits will be set to zero. S/PDIF can also transport 24-bit samples by way of four bits, however, not all equipment supports this. With one exception, S/PDIF protocol is identical to AES3, the channel status bit differs in S/PDIF. There is one channel status bit in each subframe, making 384 bits in each audio block, the meaning of the channel status bits is completely different between AES3 and S/PDIF
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TOSLINK
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TOSLINK is a standardized optical fiber connector system. 1/7.1 surround sound such as Dolby Digital Plus or DTS-HD High Resolution Audio. Unlike HDMI, TOSLINK does not have the bandwidth to carry the lossless versions of Dolby TrueHD, DTS-HD Master Audio, although TOSLINK supports several different media formats and physical standards, digital audio connections using the rectangular EIAJ/JEITA RC-5720 connector are by far the most common. The optical signal is a red light with a wavelength of 650 nm. Depending on the type of modulated signal being carried, other optical wavelengths may be present, a less common format is a coaxial cable ending in RCA jacks, which is found on some receivers. Toshiba originally created TOSLINK to connect their CD players to the receivers they manufactured, the software layer is based on the Sony Philips Digital Interconnect Format, while the hardware layer utilizes a fiber optic transmission system, rather than the electrical hardware layer of S/PDIF. TOSLINK was soon adopted by manufacturers of most CD players and it can often be found on video source to connect the digital audio stream to Dolby Digital/DTS decoders. The name is a trademark of Toshiba, created from TOShiba-LINK. Variations of the name, such as TOSlink, TosLink, and Tos-link, are also seen, ADAT Lightpipe or simply ADAT Optical uses an optical transmission system similar to TOSLINK, and is used in the professional music/audio industry. While the ADAT Lightpipe format uses the same JIS F05 connectors as TOSLINK, due to their high attenuation of light, the effective range of plastic optical cables is limited to 5–10 m. They can temporarily fail or be damaged if tightly bent. Although less commonly available and more expensive than plastic optical cables, glass or silica optical fibers have lower losses. Optical cables are not susceptible to problems such as ground loops. TOSLINK cables are limited to 5 meters in length, with a technical maximum of 10 meters. However, it is common for interfaces on newer consumer electronics to easily run over 30 meters on even low-cost TOSLINK cables. TOSLINK transmitters operate at a nominal wavelength of 650 nm. Mini-TOSLINK is an optical fiber connector smaller than the standard square TOSLINK connector commonly used in larger consumer audio equipment. The plug is almost the size and shape as the ubiquitous 3.5 mm stereo minijack. Adapters are available to connect a full-size TOSLINK plug to a mini-TOSLINK socket
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Component video
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Component video is a video signal that has been split into two or more component channels. In popular use, it refers to a type of component analog video information that is transmitted or stored as three separate signals. Component video can be contrasted with composite video in all the video information is combined into a single line level signal that is used in analog television. Like composite, component-video cables do not carry audio and are paired with audio cables. When used without any qualifications the term component video usually refers to analog YPBPR component video with sync on luma. Reproducing a video signal on a device is a straightforward process complicated by the multitude of signal sources. DVD, VHS, computers and video game consoles all store, process and transmit video signals using different methods, one way of maintaining signal clarity is by separating the components of a video signal so that they do not interfere with each other. A signal separated in this way is called component video, S-Video, RGB and YPBPR signals comprise two or more separate signals, and thus are all component-video signals. In the past, for most consumer-level applications, analog component video was used, however, component video is capable of carrying various signals, such as 480i, 480p, 576i, 576p, 720p, 1080i, 1080p, 2160p and beyond. Many new high definition TVs support the use of component video up to their native resolution, most modern computers offer this signal via a VGA port. Many televisions, especially in Europe, utilize RGB via the SCART connector, all arcade games, other than early vector and black-and-white games, use RGB monitors. In addition to the red, green and blue color signals, sync on luma, where the Y signal from S-Video is used alongside the RGB signal only for the purposes of sync. Composite sync is common in the European SCART connection scheme, RGBS requires four wires – red, green, blue and sync. If separate cables are used, the cable is usually colored yellow or white. Separate sync is most common with VGA, used worldwide for analog computer monitors and this is sometimes known as RGBHV, as the horizontal and vertical synchronization pulses are sent in separate channels. If separate cables are used, the lines are usually yellow and white, yellow and black, or gray. Sync on Green is less common, and while some VGA monitors support it, sony is a big proponent of SoG, and most of their monitors use it. Like devices that use video or S-video, SoG devices require additional circuitry to remove the sync signal from the green line
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YPbPr
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YPBPR is a color space used in video electronics, in particular in reference to component video cables. YPBPR is the version of the YCBCR color space, the two are numerically equivalent, but YPBPR is designed for use in analog systems whereas YCBCR is intended for digital video. YPBPR cables are commonly referred to as Yipper cables. YPBPR is commonly called component video by manufacturers, but this is imprecise, as there are other types of component video. Some video cards come with video-in video-out ports for connecting to component video devices, YPBPR is converted from the RGB video signal, which is split into three components, Y, PB, and PR. Y carries luma and synchronization information, Y =0.2126 R +0.7152 G +0.0722 B. Before the advent of television, the Y axis on an oscilloscope display of a video waveform represented the intensity of the scan line. With color, Y still represents intensity but it is a composite of the component colors, PB carries the difference between blue and luma. PR carries the difference between red and luma, to send a green signal as a fourth component is redundant, as it can be derived using the blue, red and luma information. When color signals were first added to the NTSC-encoded black and white video standard, P for phase information or phase shift has carried through to represent color information even in the case where there is no longer a phase shift used to represent hue. Thus, the Y PB PR nomenclature derives from engineering metrics developed for the NTSC color standard, the same cables can be used for YPBPR and composite video. Signals that use YPBPR offer enough separation that no color multiplexing is needed and it is possible for their multiplexed counterparts to interfere with each other. Among consumer analog interfaces, only YPBPR and analog RGB component video are capable of carrying non-interlaced video and resolutions higher than 480i or 576i, Color FAQ, Charles Poynton Color formats for image and video processing - Color conversion between RGB, YUV, YCbCr and YPbPr
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Composite video
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Composite video is an analog video transmission that carries standard definition video typically at 480i or 576i resolution. Video information is encoded on one channel, unlike the higher-quality S-video, Composite video is usually in standard formats such as NTSC, PAL, and SECAM and is often designated by the CVBS initialism, for color, video, blanking and sync, or simply as video. A composite video signal combines on one wire the video information required to recreate a picture, as well as line. The color video signal is a combination of the luminance of the picture, and a modulated subcarrier carries the chrominance or color information. Details of the process vary between the NTSC, PAL and SECAM systems. The burst signal is inverted in phase from the reference subcarrier, Composite video can easily be directed to any broadcast channel simply by modulating the proper RF carrier wave with it. On playback, these devices often give the user the option to output the signal or to modulate it onto a VHF or UHF frequency compatible with a TV tuner. In home applications, the video signal is typically connected using an RCA connector. It is often accompanied with red and white connectors for right, BNC connectors and higher quality coaxial cable are often used in professional television studios and post-production applications. BNC connectors were used for composite video connections on early home VCRs. The BNC connector, in turn post dated the PL-259 connector which featured on first generation VCRs. In Europe, SCART connections are used instead of RCA jacks, so where available, RGB is used instead of composite video with computers, video game consoles. Video cables are 75 ohm impedance, low in capacitance, typical values run from 52 pF/m for an HDPE-foamed dielectric precision video cable to 69 pF/m for a solid PE dielectric cable. Some devices that connect to a TV, such as VCRs, older video game consoles and home computers of the 1980s and this may then be converted to RF with an external box known as an RF modulator that generates the proper carrier. Sometimes this modulator was built into the product and sometimes it was a unit powered by the computer or with an independent power supply. In the United States, using an external RF modulator frees the manufacturer from obtaining FCC approval for each variation of a device, Video game consoles on the other hand were less of an issue with FCC approval because the circuitry was inexpensive enough to allow for channel 3/4 outputs. Modern day devices with analog outputs have typically omitted channel 3 and 4 outputs in favor of composite and S-video outputs as composite, in addition, many TV sets sold these days no longer have analog television tuners and cannot accept channel 3/4. The process of modulating RF with the video signal, and then demodulating the original signal again in the TV
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D-Terminal
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A D-Terminal or D-tanshi is a type of analog video connector found on Japanese consumer electronics, typically HDTV, DVD, Blu-ray, D-VHS and HD DVD devices. It was developed by the EIAJ in its standard, RC-5237, in appearance it is a small flat trapezic connector, the same connector as the AAUI connector used by Apple Computer for some time to connect to ethernet. Some items sold outside Japan use the connector as well, notable examples are Canons XH-A1 DVC high-definition camcorder and Panasonics AG-HVX200 DVCPro HD camcorder. A D-Terminal connector carries a component video signal, for example, a D4 connector can be used with a D4, D3, D2, or D1 signal, but not with a D5 signal. It is possible to use a breakout cable to connect a D-Terminal connector to a standard 3 RCA jack or BNC component connection. With the aforementioned diagrams, consumers should take careful consideration regarding the input and output terminals, purchased products such as the PlayStation Portable are equipped with the interface. However, since the release of System Software Ver.5.00, since 2010, the PSPs I/O system has adopted the progressive I/O interface. Furthermore, the PSP-3000 marks the possibility of interlace I/O, d-subminiature Q&A - No. 31999/10 What Is a D-Terminal. - A new terminal standard for connecting digital satellite tuners with TV sets
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DB13W3
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When used for video signals on the computer side, the pins are female but the coaxial connectors in the large positions are male. The 13W3 connector can be converted into a standard VGA connector using cables and this allows modern multisync monitors, which are common on todays computers, to be used with these workstations as long as they are sync-on-green compatible. Likewise, as many newer Sun monitors support multisync, similar cables can be used to them to modern computers. Even though 13W3 is a standard connector the sync signals are maintained on different pins based on the display, Sun Microsystems, Intergraph, IBM RISC and SGI have a different set of pins used for the monitor sense IDs and the sync signals. Sun and SGI even have two different pin configurations, with and without Display Data Channel support, the Sun DDC connector was used at least on the UPA graphics adapters and for the corresponding monitors. This can make matching the cable to the monitor virtually impossible. Many monitors with 13W3 connectors do not support separate sync as supplied on most PC systems, other converters exist to allow connecting newer monitors with VGA connectors to the older systems and workstations. The most popular of these is a cable that allows you to set the signals with a series of DIP switches built into the cables. The DB13W3 connector is used by some 3Com SuperStack Ethernet switches to carry DC power. List of display interfaces 13w3 connector applications and pinouts Example of an Apple Inc. card which uses a 13w3 connector
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VESA Digital Flat Panel
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The VESA Digital Flat Panel interface standard specifies a video connector and signaling for flat-panel displays. It features 20 pins and uses the PanelLink protocol, unlike DVI, DFP never achieved widespread implementation. The connector was used by such as the Compaq Presario FP400, FP500, FP700, Fp720,5204. It was offered on graphics cards such as the Xpert LCD, DFP was superseded by DVI because of a low maximum resolution of 1280 ×1024, whereas DVI supports much higher resolutions. DFP monitors can generally be used with a DVI graphics card with a passive adaptor, DFP diagram and description of pin layout DFP is mentioned in ATIs description of the Xpert LCD
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DMS-59
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DMS-59 is generally used for computer video cards. It provides two Digital Visual Interface or Video Graphics Array outputs in a single connector, an adapter cable is needed for conversion from DMS-59 to DVI or VGA, and different types of adapter cables exist. The connector is four pins high and 15 pins wide, with a single pin missing from the row, in a D-shaped shell. The advantage of DMS-59 is its ability to support two high resolution displays, such as two DVI Single Link digital channels or two VGA analog channels, in a single DVI-size connector. The compact size lets a half-height card support two high resolution displays, and a card up to four high resolution displays. The DMS-59 connector is used by AMD, Nvidia and Matrox for video cards sold in Lenovo Thinkcentres, Viglen Genies and Omninos, Dell, HP, and Sun computers. Some confusion has been caused by the fact that vendors label cards with DMS-59 as supports DVI, such cards, when equipped with only a VGA connector adapter cable, cannot be connected to a monitor with only a DVI-D input. A DMS-59 to DVI adapter cable needs to be used with such monitors, the DMS-59 connector is derived from the Molex low-force helix connector, which could be found in some earlier graphics cards. These ports are similar to DMS-59, but have all 60 pins present, a connector plug with all 60 pins does not fit into a properly keyed DMS-59 socket. Molex DMS-59 family description Description of DMS-59
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Low-force helix
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A low-force helix is a 60-pin electrical connector with signals for two digital and analog connectors. Each of the pins, visible in the photograph, is twisted approximately 45 degrees between the tip and the white plastic frame which holds all the pins. The LFH connector is used with workstations, because it can connect a single computer graphics source to up to four different monitors. The standard interface is a 60-pin LFH connector with two breakout VGA or DVI cables and this system provides users with flexibility for a variety of display configurations, though forsakes standard DVI or VGA connectors. This renders the LFH connector unusable without an adapter and its also used in HDCI used in Polycom HDX video conferencing systems. Using the LFH interface requires a card with multi-monitor capabilities. Currently, NVIDIA, Matrox and BFG Technologies manufacture such cards, another application of LFH capabilities is manufactured by Matrox. The Matrox card outputs via two LFH cables to a monitor, delivering 9.2 million pixels of resolution. The LFH connector is present as a network interface on Cisco routers. DMS-59 Molex Molex DMS-59 Product Page
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Digital Visual Interface
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Digital Visual Interface is a video display interface developed by the Digital Display Working Group. The digital interface is used to connect a source, such as a video display controller, to a display device. It was developed with the intention of creating a standard for the transfer of digital video content. The interface is designed to transmit uncompressed digital video and can be configured to support multiple modes such as DVI-A, featuring support for analog connections, the DVI specification is compatible with the VGA interface. This compatibility, along with other advantages, led to its widespread acceptance over competing digital display standards Plug and Display, although DVI is predominantly associated with computers, it is sometimes used in other consumer electronics such as television sets and DVD players. DVIs digital video format is based on panelLink, a serial format developed by Silicon Image that utilizes a high-speed serial link called transition minimized differential signaling. Like modern analog VGA connectors, the DVI connector includes pins for the data channel. A newer version of DDC called DDC2 allows the graphics adapter to read the monitors extended display identification data, if a display supports both analog and digital signals in one DVI-I input, each input method can host a distinct EDID. Since the DDC can only support one EDID, there can be a problem if both the digital and analog inputs in the DVI-I port detect activity and it is up to the display to choose which EDID to send. When a source and display are connected, the source first queries the displays capabilities by reading the monitor EDID block over an I²C link, the EDID block contains the displays identification, color characteristics, and table of supported video modes. The table can designate a preferred mode or native resolution, for backward compatibility with displays using analog VGA signals, some of the contacts in the DVI connector carry the analog VGA signals. To ensure a level of interoperability, DVI compliant devices are required to support one baseline video mode. Digitally encoded video pixel data is transported using multiple TMDS links, at the electrical level, these links are highly resistant to electrical noise and other forms of analog distortion. A single link DVI connection consists of four TMDS links, each link transmits data from the source to the device over one twisted wire pair. Three of the links represent the RGB components – red, green, the fourth link carries the pixel clock. The binary data is encoded using 8b10b encoding, DVI does not use packetization, but rather transmits the pixel data as if it were a rasterized analog video signal. As such, the frame is drawn during each vertical refresh period. The full active area of each frame is transmitted without compression
43.
Mini-DVI
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The Mini-DVI connector is used on certain Apple computers as a digital alternative to the Mini-VGA connector. Its size is between the full-sized DVI and the tiny Micro-DVI and it is found on the 12-inch PowerBook G4, Intel-based iMac, the MacBook Intel-based laptop, the Intel-based Xserve, the 2009 Mac mini, and some late model eMacs. In October 2008, Apple announced the company was phasing Mini-DVI out in favor of Mini DisplayPort, Mini-DVI connectors on Apple hardware are capable of carrying DVI, VGA, or TV signals through the use of adapters, detected with EDID via DDC. This connector is used in place of a DVI connector in order to save physical space on devices. Mini-DVI does not support dual-link connections and hence cannot support resolutions higher than 1920×1200 @60 Hz, the physical connector is similar to Mini-VGA, but is differentiated by having four rows of pins arranged in two vertically stacked slots rather than the two rows of pins in the Mini-VGA. Connecting to a DVI-I connector requires a Mini-DVI to DVI-D cable plus a DVI-D to DVI-I adapter, Apples Mini-DVI to DVI-D cable does not carry the analog signal coming from the mini-DVI port on the Apple computer. This means that it is not possible to use this cable with an inexpensive DVI-to-VGA adapter for VGA output and this could be avoided if Apple provided a mini-DVI to DVI-I cable. The purpose of DVI-I is to ensure universal compatibility, the Apple mini-DVI to DVI-D cables package shows a DVI-I figure instead of DVI-D and does not specify that it comes with only DVI-D. As Mini-DVI is pin-compatible with DVI, it supports both DVI and VGA through adapters, DVI Micro-DVI Mini DisplayPort 12-inch PowerBook G4 Developer Note, External Display Port Hdmi-to-dvi cables connection
