Left to right, modular connectors: < ul > < li > eight-contact 8P8C plug ( used for RJ45, RJ49, RJ61 and others )</ li > < li > six-contact 6P6C plug used for RJ25 </ li > < li > four-contact 6P4C plug used for RJ14 ( often also used instead of 6P2C for RJ11 )</ li > < li > four-contact 4P4C handset plug ( also popularly, though incorrectly, called " RJ9 ", " RJ10 ", or " RJ22 ")</ li > </ ul > RJ11, RJ14, and RJ25 can be plugged into the same six-pin 6P6C jack, pictured.

The standard designs for these connectors and their wiring are named RJ11, RJ14, RJ21, RJ45, RJ48, etc.

The six-position plug and jack commonly used for telephone line connections may be used for RJ11, RJ14 or even RJ25, all of which are names of interface standards that use this physical connector.

The RJ11 standard dictates a 2-wire connection, while RJ14 uses a 4-wire configuration, and RJ25 uses all six wires.

6P4C crimp-on style connector commonly used for RJ11 and RJ14

Essentially all one, two, and three line analog telephones made today ( 2009 ) are meant to plug into RJ11, RJ14, or RJ25 jacks, respectively.

Cables sold as RJ11 often use 6P4C RJ14 connectors ( six position, four conductor ), with four wires running to a central junction box.

* Registered jack ( RJ11, RJ14, RJ45, etc.

No adapter is needed in the U. S. as the 6P2C and 6P4C plugs most commomly used with RJ11 and RJ14 telephone connections are physically and electrically compatible with the larger 8P8C socket.

The Trimline was also one of the first phones to use the predecessor of the now-ubiquitous RJ11 modular phone plug and jack.

As of 2004, new telephone installations in South Africa use RJ11 plugs ( which are sometimes referred to in South Africa as Venus plugs ), but Protea plugs are still often encountered in older installations.

The GX4000 supports the use of a lightgun through its dedicated RJ11 lightgun connector.

For example, RJ11 uses a 6 position 2 conductor ( 6P2C ) modular plug and jack, while RJ21 uses a 50-pin miniature ribbon connector.

In such systems, RJ11 ( 6P2C or 6P4C modular plugs, commonly used for telephones ) are popular.

The standard for telephone plugs varies from country to country, though the RJ11 " modular connector " has become by far the most common.

For example, telephone cables in the UK typically have a BS 6312 ( UK standard ) plug at the wall end and a 6P4C or 6P2C modular connector at the telephone end: this latter may be wired as per the RJ11 standard ( with pins 3 and 4 ), or it may be wired with pins 2 and 5, as a straight through cable from the BT plug ( which uses pins 2 and 5 for the line, unlike RJ11, which uses pins 3 and 4 ).

The design is only used in Sweden and older installations in Iceland ( RJ11 and a data / voice standard using an 8P8C modular connector are used in more recent buildings ).

The LC, as with a number of other Macs of the day, featured built-in networking via " PhoneNet " that used standard RJ11 phone cabling and connector boxes.

A connection standard, such as " RJ11 ", specifies not only the physical connector, but how it is wired ( the " pinout ").

Audio output, 2x Digital controller connectors, Analog controller port ( IBM standard ), Lightgun connector ( RJ11 ), Audio and RGB Video output ( 8-pin DIN ), Power supply socket from external PSU, Power supply socket from monitor.

Today the standard electrical connector for interconnection in the US, and much of the world, is the registered jack family of standards, especially RJ11.

Telephone jacks are also British Standard BS 6312, as opposed to the RJ11 versions found in other parts of Europe and the world.

The terms phone plug and phone jack are sometimes used to refer to TRS connectors, but are also sometimes used colloquially to refer to RJ11 and older telephone plugs and the corresponding jacks that connect wired telephones to wall outlets ( the similar terms phono plug and phono jack ( or in the UK, phono socket ) refer to RCA connectors common in consumer HiFi and Audio Visual equipment ).

The connectors could be supplied with more pins, but if more pins are actually wired, the interface is no longer an RJ11.

The telephone line cord and its plug are more often a true RJ11 with only two conductors.

Thus cables are not in general compatible between different phones, as the phone base may have a socket with pins 2 and 5 ( requiring a straight through cable ), or have an RJ11 socket ( requiring a crossover cable ).

In that case, the jacks in the house are RJ11.

In addition to the standard Swedish plugs and sockets, RJ11 connectors are quite common, especially in offices.

The Cat's array of I / O interfaces encompassed one Centronics parallel port, one RS-232C serial port ( DB-25 ), and two RJ11 telephone jacks for the modem loop.

* 6P2C for RJ11 single telephone line

In modern makes it does nothing electrical, and capacitor compartment was reused for additional RJ11 socket.

* An RJ11 jack for the ADSL connection ;

* An RJ11 jack for phone equipment ( two jacks on versions 1 & 2 but only one active );

* Registered jack, a set of standards for telecommunications cabling termination ( including RJ11, RJ15, and RJ45 )

Generally this requires some hand-crimping of a cable using three RJ11 jacks, connecting a single jack to two, one with two wires for the phone and the other with the other two for networking.

These access devices can range from small Analog Telephone Adaptors ( ATA ) which provide just one RJ11 telephone jack to an Integrated Access Device ( IAD ) or PBX which may provide several hundred telephone connections.

Many come equipped with a regular RJ11 Phone Jack for making PSTN calls, using an ordinary telephone handset, and many terminals have an ISDN connection to do ISDN phone calls.

* Two or more traditional analog ( RJ11 ) access lines to a voice-over-IP ( VoIP ) network.

This distinction is exemplified by a telephone system with a connected modem, where the RJ11 connection and associated modulated signaling scheme is not considered a bus, and is analogous to an Ethernet connection.

In many households, telephones were hard-wired to wall terminals before connectors like RJ11 and BS 6312 became standardised.

RJ11 uses a 6P2C.

The most familiar registered jack is probably the RJ11.

It is often 6P4C, which is often RJ11, but may be proprietary or hardwired.

Image: WT-4 & RJ11 telephone socket. png | WT-4 and RJ11 telephone socket ( double system )