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Modular connector

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This article is about modular connectors. For the Registered Jack (RJ) wiring standard, see Registered jack.
Left to right, modular connectors: 8P8C plug, 6P6C plug, 6P4C plug, 4P4C plug, 6P6C jack.
An 8P8C modular plug. This is the common crimp type plug, of the same kind pictured above crimped onto a cable (with moulded sleeve)

Modular connector is the name given to a family of electrical connectors examples of which are pictured. These connectors were originally used in telephone wiring. Even though they are still used for that purpose they are used for a variety of other things as well. A modular connector's advantage over many other kinds include small size and ease of plugging and unplugging. However the plastic retaining spring clip tends to get broken off when cables are pulled from storage for use. If that happens, the plug can easily fall out of the wall jack. Many uses that originally used a bulkier connector have migrated to modular connectors. Probably the most well known applications of modular connectors is for telephone jacks and for Ethernet jacks, which are nearly always modular connectors.

Modular connectors were first used in the Registered Jack system, so Registered Jack specifications describe them precisely. Those are the specifications to which all practical modular connectors are built. However, the Registered Jack specifications name the wiring patterns of the jacks, not the physical connectors of either sex. Instead, these are covered by ISO standard 8877, first used in ISDN systems.

It is important to note that connectors are made for solid or stranded wire, especially when using 8P8C ethernet cable connectors. A stranded wire connector may not reliably contact a solid wire.

Nomenclature

Main article: Registered jack naming confusion

Modular connectors also go by the names "modular phone jack/plug", "RJ connector," and "Western jack/plug."

It is very common, but incorrect, to use a Registered Jack number to refer to the physical connector itself; for instance, the 8P8C modular connector type is often loosely called RJ45 (for a standard that uses this connector), but 8P8C connectors are also used with different wiring, such as for Ethernet over twisted pair — in fact, the RJ45 wiring pattern is almost obsolete.

The term "modular connector" is not terribly descriptive, but arose from its original use in a novel system of cabling designed to make telephone systems more modular. This includes the 4P4C handset connector which is often referred to as an RJ9 or an RJ22—both of these are incorrect, since 4P4C connectors were not used to connect to carrier circuits at all: there is no valid Registered Jack number for the 4P4C[citation needed].

History

Modular connectors were originally invented and patented by Bell Telephone Laboratories (patent filed 6 July 1973; U.S. patent 3,860,316 issued 14 January 1975), and replaced the hard-wired connections on most Western Electric telephones around 1976. At the same time, they began to replace screw terminals and large 3 and 4 pin jacks in buildings.

Gender

Modular connectors have gender: male connectors are called plugs, while female connectors are called jacks or, sometimes, sockets.

The choice of gender is generally based on the location of the connector: plugs are used to terminate loose cables and cords, while jacks are used for fixed locations on surfaces such as walls and panels. (This is in contrast to some other connector systems, where the choice of gender is based on the function of the connector: for example, in power cabling systems, female connectors deliver power, while male connectors receive power.) Cables with a plug on one end and a jack on the other are rare; instead, cables that have the more common arrangement of plugs on both ends are connected using a male-to-male adapter, which has two jacks.

Locking and hook

Modular connectors are designed to lock together. A spring-loaded tab called a "hook" on the plug snaps into a jack so that the plug cannot be pulled out. To remove the plug, the hook must be depressed. The most common way to install a jack in a wall or panel is with the hook side down. This usually makes it easier to operate the hook when removing the plug, because the person grabs the plug with thumb on top and presses the hook with the index finger.

The modular connector, however, suffers from very poor design as the fragile hook easily snags on other cables and breaks. In this case, the connector is still basically functional as it can be slotted back into the jack, but it makes the connection unreliable if any device is moved or cables adjusted. Some higher quality cables have a flexible sleeve called a "boot" over the plug, or a special hook design, to prevent this. These cables are often marketed as "snagless". Boots are seen mainly on 8P8C data cables.

Sizes and contacts

Modular connectors have positions, some or all of which have contacts in them, some or all of which have wires attached; positions with omitted contacts or contacts unattached to wires are unused for the electrical connection, but ensure that the plug fit correctly. For instance, RJ11 wires usually have connectors with 6 positions and 4 contacts, to which are attached 2 wires.

Modular connectors come in four sizes: 4-, 6-, 8-, and 10-position, where a position is a location for a contact. Not all of the positions may have contacts: when contacts are omitted, they are typically done so from the outermost two contacts inward, such that the number of contacts is always an even number.

The connectors are typically designated using two numbers that represent the quantity of positions and contacts, with each number followed by a "P" and "C", respectively: for example, "6P2C" for a connector having 6 positions and 2 contacts. Alternate designations omit the "P" and "C" while separating the position and contact quantities with either an "x" ("6x2") or a slash ("6/2").

The dimensions of the connectors are such that a plug can be inserted into a jack that has more positions than the plug, leaving the jack's outermost contacts unterminated. However, not all plugs from all manufacturers have this capability, and some jack manufacturers warn that their jacks are not designed to accept smaller plugs without damage.

8P8C modular plug pin positioning

When all of the positions have contacts, the contacts are numbered sequentially starting from 1. When viewed head-on with the retention mechanism on the bottom, jacks will have contact number 1 on the left and plugs will have it on the right. If the connector has positions that do not have contacts, the remaining contacts are numbered as if all of the positions had contacts: for example, on a 6-position, 2-contact plug, where the outermost four positions do not have contacts, the innermost two contacts are numbered 3 and 4.

Some modular connectors are indexed: their dimensions are intentionally non-standard, preventing connections with connectors of standard dimensions. The means of indexing may be non-standard cross-section dimensions or shapes, retention mechanism dimensions, or retention mechanism quantity.

Pinouts

See also: Registered jack, Ethernet over twisted pair, and RS-232 § Pinouts

Contact assignments, or pinouts, vary by application. While standardized for telephone applications by registered jack standard, and Ethernet over twisted pair by the TIA/EIA-568-B standard, there may be no standardization within an application: for example, there are multiple conventions for use of 8P8C connectors for RS-232.

For this reason, D-sub-to-modular adapters are typically shipped without the D-sub contacts (pins or sockets) terminated, so that the D-sub-to-modular contact pairing can — and must — be performed by the end-user.

4P4C

4P4C modular connector on a handset cable
Wired telephone using 4P4C connectors

The 4P4C connector, an Acronym for 4 Position, 4 Conductor (Sometimes the second "C" is referred to as a Contact, it stands for Conductor. While the "tine" is a contact, the name comes from the bandwidth that the cable will allow. A 4P4C will allow up to 4 Conductors, even though the connector itself has tines commonly referred to as Contacts); it is popularly, but incorrectly, called RJ22, RJ10, or RJ9. It is also commonly referred to as a "Handset Connector" because of the most popular usage for the connector.[1] It is the de facto industry standard for wired telephone handsets. It is used to provide connection from the base of the telephone to the handset.

"RJ" stands for Registered Jack, a family of telephone connection standards. This handset connector is actually not a Registered Jack at all, since it was never intended to connect directly to the telephone service lines: RJ connects a phone to the service lines, while 4P4C connects two parts of a phone. It uses the 4P4C modular connector, which has four pins or electrical connections per connector. While all other RJ connectors are in use, and used in the field, by telephone companies; the 4P4C is unique in that it is for an End User only application, mainly from the phone to the handset.

Wiring

Wiring diagram for handset use of 4P4C/RJ9 plug When used for connecting handsets to the telephone base, the following pinout and wiring diagram is most often (but not always) used. The handset's speaker (usually called the "transducer") continues to function normally with reversed wires, but the electret microphone element used in most modern handsets cannot, as it is polarity dependent. The cable connecting the handset itself can be wired as a simple crossover cable or as a straight through cable, most telephone handset cords are manufactured as crossover cables.[2] Whatever wiring is used, you cannot switch over to the other kind, or the microphone (but not the speaker) will cease to function. In most of the 20th century carbon microphones were used that were not polarity dependent. The "transducers" in most handsets have higher impedances than most small loudspeakers, often hundreds of Ohms instead of the 8 Ohm of a typical speaker. A transducer is encapsulated in an airtight enclosure, so sound waves (air pressure variations) cannot enter the inside of the handset, reaching the microphone.

Data port

The Macintosh 128K, Macintosh 512K and Macintosh Plus from Apple used 4P4C connectors to connect the keyboard to the main computer housing. The connector provided power to the keyboard on the outer two conductors and received data signals on the inner pair. The cable between the computer and the keyboard was a coiled cord with an appearance very similar to a telephone handset cable.[3] The connector wiring, however, required a polarized straight through pinout. Using a telephone handset cable instead of the supplied cable could short out the +5 volt DC supply and damage the computer or the keyboard.[4]

Some consumer equipment such as DirecTV set top boxes include a 4P4C low-speed data port connector.[2] Such connectors can be adapted for use with a computer's serial port so that control commands can be sent from the computer to the set top box.

6P6C

The 6P2C, 6P4C, and 6P6C modular connectors are probably most well known for their use as RJ11, RJ14, and RJ25 registered jacks respectively.

RJ11 is a physical interface often used for terminating telephone wires. It is probably the most familiar of the registered jacks, being used for single line POTS telephone jacks in most homes across the world.

RJ14 is similar, but for two lines, and RJ25 is for three lines. RJ61 is a similar registered jack for four lines. The telephone line cord and its plug are more often a true RJ11 with only two conductors.

Modular plugs are described as containing a number of potential contact "positions" and the actual number of contacts installed within these positions. RJ11, RJ14, and RJ25 all use the same six-position modular connector, thus are physically identical except for the different number of contacts (two, four and six respectively).

RJ11 wiring

RJ14 6P4C crimp-on style connector
RJ14 6P4C crimp-on style connector
Main article: RJ11

Cables sold as RJ11 often actually use 6P4C RJ14 connectors (six position, four conductor), with four wires running to a central junction box. Two of its six possible contact positions connect tip and ring, and the other two conductors are then unused. 6P2C and 6P6C can also be found in stores.

The conductors other than the two central tip and ring conductors are in practice used for various things such as a ground for selective ringers, low voltage power for a dial light, or for 'anti-tinkle' circuitry to prevent pulse dialing phones from ringing the bell on other extensions. With tone dialing, anti-tinkle measures are not required.

Pinouts

The multi-conductor cables attached to RJ11 connectors usually have colored sheaths.

position RJ25 pin RJ14 pin RJ11 pin Pair T/R ± Cat 5e/6 colors Colors Old colors German
colors[5]
1 1 3 T + Pair 3 Wire 1 Cat 5e/6 white/green Pair 4 Wire 1 white/green Pair 3 wire 1 white Pair 3 wire 1 pink
2 2 1 2 T + Pair 2 Wire 1 Cat 5e/6 white/orange Pair 2 Wire 1 white/orange Pair 2 Wire 1 Old black Pair 2 ext. bell green
3 3 2 1 1 R – Pair 3 Wire 2 Cat 5e/6 blue Pair 1 Wire 2 blue/white Pair 1 Wire 2 Old red Pair 1 wire A white
4 4 3 2 1 T + Pair 1 Wire 1 Cat 5e/6 white/blue Pair 1 Wire 1 white/blue Pair 1 Wire 1 Old green Pair 1 wire B brown
5 5 4 2 R – Pair 3 Wire 1 Cat 5e orange Pair 2 Wire 2 orange/white Pair 2 Wire 2 Old yellow Pair 2 ground yellow
6 6 3 R – Pair 1 Wire 1 Cat 5e green Pair 3 Wire 2 green/white Pair 3 Wire 2 blue Pair 3 wire 2 gray

While the old solid color code was well established for pairs 1 and 2, there are several conflicting conventions for pair 3. The colors shown above were taken from a vendor of "silver satin" flat 8-conductor phone cable that claims to be standard. Other 6 pair solid (old) bellwire cables may substitute white for orange. At least one other vendor of flat 8-conductor cable uses the sequence blue, orange, black, red, green, yellow, brown and white/slate.

Holding the connector in your hand tab side down with the cable opening toward you, the pins are numbered 1-6, left to right.

Powered version of RJ11

In the powered version, Pins 2 and 5 (black and yellow) may carry low voltage AC or DC power. While the phone line itself (tip and ring) supplies enough power for most telephone terminals, old telephone terminals with incandescent lights in them (such as the classic Western Electric Princess and Trimline telephones) need more power than the phone line can supply. Typically, the power on Pins 2 and 5 comes from a transformer plugged into a wall near one jack, supplying power to all of the jacks in the house. Trimline and Princess phone dial lights are rated at 6.3 volts and the transformer output is typically around 5 volts, providing a long service life for the incandescent lamps.

Compatibility with Structured Cabling

With the rise of Ethernet local area networks operating over Cat5e and Cat6 unshielded twisted pair cable, structured cabling networks adhering to TIA/EIA-568-B are widely used for both computer networking and analog telephony. The 8P8C ("RJ45") jack used by TIA/EIA-568-B physically accepts the 6-position connector used by RJ11, RJ14 and RJ25, but only RJ11 and RJ14 have full electrical compatibility. TIA/EIA-568-B "splits" the third pair of RJ25 across two separate cable pairs, rendering it unusable. This was necessary to preserve the electrical properties of those pairs for Ethernet, which operates at much higher frequencies than analog telephony.

Both the third and fourth pairs of RJ61 are similarly split. Because of this incompatibility, and because they were never very common to begin with, the TIA/EIA-568-B conventions are displacing RJ25 and RJ61 for telephones with more than two lines.

8P8C

This article is about the generic 8P8C modular connector. For the RJ45 connector used in telephone installations, see RJ45. For the Registered Jack (RJ) wiring standard, see Registered jack.
An 8P8C modular plug before being crimped onto a cable
Connector and cable

The 8P8C (8 Position 8 Contact, also backronymed as 8 position 8 conductor; often called RJ45[6]) is a modular connector commonly used to terminate twisted pair and multiconductor flat cable. These connectors are commonly used for Ethernet over twisted pair, Registered jacks and other telephone applications, RS-232 serial using the EIA/TIA 561 and Yost standards, and other applications involving unshielded twisted pair, shielded twisted pair, and multiconductor flat cable.

An 8P8C modular connector has two paired components: the male plug and the female jack, each with eight equally-spaced conducting channels. On the plug, these conductors are flat contacts positioned parallel with the connector body. Inside the jack, the conductors are suspended diagonally toward the insertion interface. When an 8P8C plug is mated with an 8P8C jack, the conductors meet and create an electrical connection. Spring tension in the jack's conductors ensure a good interface with the plug and allow for slight travel during insertion and removal.

Although commonly referred to as an RJ45[7] in the context of Ethernet and category 5 cables,[8][9] it is technically incorrect to refer to a generic 8P8C connector as an RJ45.[10] The registered jack (RJ) standard specifies a different mechanical interface and wiring scheme for a true RJ45 than TIA/EIA-568-B which is often used for modular connectors used in Ethernet and telephone applications. 8P8C modular plugs and jacks look very similar to the plugs and jacks used for FCC's registered jack RJ45 variants, although the true RJ45 is not compatible with 8P8C modular connectors.

"RJ45" naming confusion

See also: Registered jack naming confusion

RJ45 was originally a telephone-only standard. It is one of the many registered jacks, like RJ11, another telephone standard. As a registered jack, telephone RJ45 specifies the physical male and female connectors as well as the pin assignments of the wires in a telephone cable. The original RJ45 uses a special[11][12] keyed 8P2C modular connector, with Pins 5 and 4 wired for tip and ring of a single telephone line and Pins 7 and 8 connected to a programming resistor. It is meant to be used with a high speed modem, and is obsolete today.

Telephone installers who wired telephone RJ45 jacks were familiar with the pin assignment which was part of the RJ45 standard. However, near-identical physical connectors for computer networking became ubiquitous, and informally inherited the name RJ45 due to the overwhelming similarity. While telephone RJ45 uses a "keyed" variety of the 8P body, meaning it may have an extra tab that a computer RJ45 connector is unable to mate with, the visual difference from an Ethernet 8P is subtle.

The only other difference is the presence of extra conductors in the cable, which cannot be seen without very close inspection. True telephone RJ45 connectors are a special variant of 8P2C, meaning only the middle 2 positions have conductors in them, while pins 7 and 8 are shorting a programming resistor. Computer RJ45 is 8P8C, with all eight conductors present.

Understandably, because telephone RJ45 8P connectors never saw wide usage and computer 8P connectors are quite well known today, RJ45 is used almost exclusively to refer to Ethernet-type computer connectors. Electronics catalogs not specialized to the telephone industry advertise 8P8C modular connectors as "RJ45". Virtually all electronic equipment that uses an 8P8C connector (or possibly any 8P connector at all) will document it as an "RJ45" connector. In common usage, RJ45 also refers to the pin assignments for the attached cable, which are actually defined in the wiring standard TIA/EIA-568-B.

Standardization

The shape and dimensions of an 8P8C modular connector are specified for U.S. telephone applications by the Administrative Council for Terminal Attachment (ACTA) in national standard ANSI/TIA-1096-A. This standard does not use the short term 8P8C and covers more than just 8P8C modular connectors, but the 8P8C modular connector type is the eight position connector type described therein, with eight conductors installed.

For data communication applications (LAN, structured cabling), International Standard IEC 60603 specifies in parts 7-1, 7-2, 7-4, 7-5, and 7-7 not only the same physical dimensions, but also high-frequency performance requirements for shielded and unshielded versions of this connector for frequencies up to 100, 250 and 600 MHz, respectively.

Wiring

T568A wiring
T568B wiring

Connectors are frequently terminated using the T568A or T568B pin/pair assignments that are defined in TIA/EIA-568-B. A cable that is wired as T568A at one end and T568B at the other (Tx and Rx pairs reversed) is a "crossover" cable. Before the widespread acceptance of auto-MDI/MDIX capabilities a crossover cable was needed to interconnect similar network equipment (such as hubs to hubs). Crossover cables are still used today to connect two computers together without a switch or hub. A cable wired the same at both ends is called a "patch" or "straight-through" cable, because no pin/pair assignments are swapped.

Types

Two types of 8P8C plugs and installation tools (used for crimping the plug onto a cable) are commonly available: Western Electric/Stewart Stamping (WE/SS) and Tyco/AMP. While both types look remarkably similar, the tooling used to install the two different plug types is mutually exclusive and cannot be interchanged between the two types. WE/SS compatible plugs are available from a large number of manufacturers, whereas Tyco/AMP plugs are produced exclusively by Tyco Electronics. Both types of modular plugs will plug into the same standard 8P8C modular jack.

WE/SS and Tyco/AMP 8P8C plugs have different spacing for the cable strain relief.[13][14] As a result, using a WE/SS 8P8C crimp dieset on a Tyco/AMP 8P8C plug will crush the top of the connector, and vice versa. While the WE/SS compatible plug is produced by a larger number of manufacturers than the Tyco/AMP plug, it is still important to know what style is being used to avoid damaging the plug during crimping.

Both types of 8P8C plugs are available in shielded and unshielded varieties, depending on the attenuation tolerance needed. Shielded plugs are more expensive and require shielded cable, but have a lower attenuation and can reduce signal noise.

Termination

Termination of a cable with an 8P8C plug involves using a hand crimper or crimp machine containing an 8P8C die-set or an A67T[citation needed] standard die-set. An 8P8C crimp die-set usually looks similar to an 8P8C jack, except for the eight teeth lining the top portion of the die. When the tool is operated, the die compresses around the 8P8C plug. As the die compresses, these teeth force the plug contacts down into the conductors of the cable being terminated, permanently attaching the plug to the cable. The crimper may also permanently deform part of the plug body in such a way that it grips the outer sheath of the cable. This helps to keep the plug securely fastened to the end of the cable, by providing strain relief.

Applications

8P8C are commonly used in computer networking and telephone applications, where the plug on each end is an 8P8C modular plug wired according to a TIA/EIA standard. Most network communications today are carried over Category 5e or Category 6 cable with an 8P8C modular plug crimped on each end.

The 8P8C modular connector is also used for RS-232 serial interfaces according to the EIA/TIA-561 standard.[15] This application is commonly used as a console interface on network equipment such as switches and routers. Other applications include other networking services such as ISDN and T1.

In floodwired[16] environments the center (blue) pair is often used to carry telephony signals. Where so wired, the physical layout of the 8P8C modular jack allows for the insertion of an RJ11 plug in the center of the jack, provided the RJ11 plug is wired in true compliance with the U.S. telephony standards (RJ11) using the center pair. The formal approach to connect telephony equipment is the insertion of a type-approved converter.

The remaining (brown) pair is increasingly used for Power over Ethernet (PoE). Legacy equipment may use just this pair; this conflicts with other equipment as manufacturers used to short circuit unused pairs to reduce signal crosstalk.[citation needed] Some routers/bridges/switches can be powered by the unused 4 lines — blues (+) and browns (−) — to carry current to the unit. There is now a standardized scheme for Power over Ethernet.

Different manufacturers of 8P8C modular jacks arrange for the pins of the 8P8C modular connector jack to be linked to wire connectors (often IDC type terminals) that are in a different physical arrangement from that of other manufacturers: Thus, for example, if a technician is in the habit of connecting the white/orange wire to the "bottom right hand" IDC terminal, which links it to 8P8C modular connector pin 1, in jacks made by other manufacturers this terminal may instead connect to 8P8C modular connector pin 2 (or any other pin).

10P10C

The pin arrangement for a 10P10C socket

The 10P10C modular connector is a type of electrical connector.

Terminology

The 10P10C connector is commonly referred to as an RJ50 connector, although this is not a standard registered jack in the Universal Service Order Codes. The 10P10C is a telephone-style connector featuring 10 pins and 10 connection wires.

Common Uses

The most common uses of the 10P10C connector are in proprietary data transfer systems,[17] such as the Digi International Digiboard serial connections.[18] It is also used to implement the RS-232 and RS-485 connector standards. It is also used in APC uninterruptible power supplies. In this case, it is a keyed 10P10C plug with a protrusion on the pin 1 side near the back.

This connector is also used by some vendors for expansion modules of their multi-port RS-232C serial boards. For example, Cyclades used the pin #1 as a "RI" (Ring Indicator) signal, which is rarely used, allowing an RJ45 connector to be plugged to their RJ50 socket for most applications. The Cisco Systems STS-10X terminal server featured this connector. FordNet, a five-pair communications networking medium also used the 10P10C between terminals.

See also

Wikimedia Commons has media related to Modular connectors.

References

  1. ^ BICSI (October 7, 2002). "Background Information". Telecommunications Cabling Installation (2nd ed.). McGraw-Hill Professional. p. 88. ISBN 0-07-140979-3. 4-position and 4-contact connectors are used primarily for telephone handset cords.
  2. ^ a b GBPVR Wiki. Direc TV Channel Control. "Each end of a handset cord is wired opposite the other..."
  3. ^ My Old Computers. Apple Macintosh Plus
  4. ^ Syrinx. Mac Plus Keyboard Cable. "...the cable is the same as the telephone cable that connects handsets to the phone, unfortunately [...] this type of cable and pretty much any type of pre manufactured cable [...] is wired wrong for the Mac Plus. Under no circumstances should you use this cable as you will damage your keyboard and/or your Mac!"
  5. ^ This different color scheme is in use in Germany and some neighboring countries, and may be encountered with equipment manufactured in or for these countries. However, with German domestic telephone equipment, 6P4C plugs and sockets are typically only used to connect the telephone cable to the phone base unit. To connect the telephone cable to the phone jack at the other end, the mechanically different TAE socket and connector is used. A standard German phone cable thus has a TAE plug at the phone jack end and an RJ11- or RJ14-wired 6P4C plug at the phone end, with the wires color-coded as shown. The third wire pair (pink/gray) and fully RJ25-wired 6P6C plugs and sockets are very rare in domestic telephone equipment. Usually just four wires as per RJ14 are present.
  6. ^ Trulove, James (December 19, 2005). "Designing LAN Wiring Systems". LAN wiring (3rd ed.). McGraw-Hill Professional. p. 23. ISBN 0-07-145975-8. The 8-pin modular jack is sometimes referred to as an "RJ-45," because the connector/jack components are the same. However, RJ-45 actually applies to a special purpose jack configuration that is not used in LAN or standard telephone wiring.
  7. ^ Trulove, James (December 19, 2005). "Work Area Outlets". LAN wiring (3rd ed.). McGraw-Hill Professional. p. 132. ISBN 0-07-145975-8. Modular jacks are often referred to as "RJ-45" jacks. This is not really the correct moniker, although it is in very common use.
  8. ^ Oliviero, Andrew; Woodward, Bill (July 20, 2009). "Connectors". Cabling: The Complete Guide to Copper and Fiber-Optic Networking (4th ed.). Sybex. p. 294. ISBN 0-470-47707-5. The RJ (registered jack) prefix is one of the most widely (and incorrectly) used prefixes in the computer industry; nearly everyone, including people working for cabling companies, is guilty of referring to an eight-position modular jack (sometimes called an 8P8C) as an RJ-45.
  9. ^ Semenov, Andrey B.; Strizhakov, Stanislav K.; Suncheley, Igor R. (October 3, 2002). "Electrical Cable Connectors". Structured cable systems (1st ed.). Springer. p. 129. ISBN 3-540-43000-8. The traditional 8-contact connector, which is called Western Plug, 8PMJ (8-position modular jack), 8P8C (8 position 8 conductor), or somewhat incorrectly RJ-45, is used widely in SCS practice.
  10. ^ Trulove, James (December 19, 2005). "User Cords and Connectors". LAN wiring (3rd ed.). McGraw-Hill Professional. p. 219. ISBN 0-07-145975-8. This 8-pin modular plug is probably the most subject to name abuse, because it resembles the specialized RJ-45 connector. However, the RJ-45 wiring pattern (which includes an interface programming resistor) is so radically different from that of T568A and B that it really should not be called by that name at all.
  11. ^ , Ontario, CA: HVS http://www.hvs.on.ca/modular_jack_wiring.htm {{citation}}: Missing or empty |title= (help); Unknown parameter |tile= ignored (|title= suggested) (help)
  12. ^ Modular wiring reference, Siemon
  13. ^ "Stewart Connector 937-SP-3088 - Eight conductor/eight position line cord module" (PDF). Glen Rock, Pennsylvania: Bel Stewart Connector. 2006-02-01. Retrieved 2009-09-10.
  14. ^ "Tyco/AMP 5-554739-2 - Modular plug assembly, 8 position, flat oval cable" (PDF). Harrisburg, Pennsylvania: Tyco Electronics Corporation. 2008-03-31. Retrieved 2009-09-10.
  15. ^ http://www.zytrax.com/tech/layer_1/cables/tech_rs232.htm#rj45
  16. ^ floodwire is a chiefly British term for installing communications cables in a massive fashion in anticipation of their eventual use.
  17. ^ 10 pin RJ50 (10P10C) male connector diagram and applications
  18. ^ Digi PortServer TS 10P10C (RJ50) Modular RS-232 pinout
  • ANSI/TIA-968-A: Telephone terminal equipment – Technical requirements for connection of terminal equipment to the telephone network
  • IEC 60603-7-1: Connectors for electronic equipment — Part 7-1: Detail specification for 8-way, shielded free and fixed connectors with common mating features, with assessed quality
  • IEC 60603-7-2: Connectors for electronic equipment — Part 7-2: Detail specification for 8-way, unshielded, free and fixed connectors, for data transmissions with frequencies up to 100 MHz
  • IEC 60603-7-4: Connectors for electronic equipment — Part 7-4: Detail specification for 8-way, unshielded, free and fixed connectors, for data transmissions with frequencies up to 250 MHz
  • IEC 60603-7-5: Connectors for electronic equipment — Part 7-5: Detail specification for 8-way, shielded, free and fixed connectors, for data transmissions with frequencies up to 250 MHz
  • IEC 60603-7-7: Connectors for electronic equipment — Part 7-7: Detail specification for 8-way, shielded, free and fixed connectors, for data transmissions with frequencies up to 600 MHz
  • ISO/IEC 8877, EN 28877: Information Technology - Telecommunications and Information Exchange between Systems - Interface Connector and Contact Assignments for ISDN Basic Access Interface Located at Reference Points S and T

Further reading

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