RJ is the connector used in telephone wiring. RJ is short for ‘Registered Connector’ and is a physical connector interface used in telephone cable terminals. There are many design standards for registered connectors and these include RJ11, RJ14, RJ45, etc.
An RJ11 connector has a total of six connector positions, but of the many positions only two or four are used. The RJ connector comes in two forms: one which is the flat satin form and the other which is the unshielded twisted pair form. It is the most common of the registered connectors and is used primarily in homes and offices in North America. Since an RJ11 connector uses two of the six positions, it can be connected with a variety of 6P2C modular connector. However, you should be aware that these connectors are rarely used.
In addition to being used in telephone cable terminals, RJ11 connectors are also used in selective ringing, anti-jingle circuits, and selective ringing. In the powered version of the RJ11 connectors, the low voltage is carried by pins 2 and 5. The power to these pins comes from a transformer that is plugged into the wall. Four-wire cables with 6P4C plugs are used to insert telephone terminals into the RJ11 jacks.
Very often, a comparison is made between RJ11 and RJ45 connector. RJ11 is used to connect telephone systems, but RJ45 is used to connect systems on a network. The RJ45 connector is larger and can accommodate more cables than the RJ11.
RJ11 is the most common type of register today and is used to terminate telephone lines. These are typically used with single line POTS (Old Standard Telephone Service) headphone jacks. When using an RJ11 conductor, be sure to follow all instructions so that your connection to any device is successful.
