Registered jacks are the physical connectors that were introduced in 1986 by Bell Systems under the request of the US Federal Communication Commission. They are telephonic lines that have a different serial number to be able to differentiate them from one another and for making them unique for each user.
Only the delivery of these is taken care of by the telephone services while the customers are required to maintain them. They were used as a protective replacement for the protective couplet provided by the companies. There are many types of registered jacks depending on their functions. Two of them are RJ11 and RJ14.
RJ-11 vs RJ-14
The main difference between RJ11 and RJ14 is that the negative and positive wires of RJ11 connect to pin 3 and pin 4 respectively whereas the negative and positive wires of RJ14 connect to pin 2 and pin 5 respectively. The only similarity they have in connection is that they both have two terminals.
RJ11 or registered jack 11 which is also commonly known as phone connector or modem port. They were used by the US Commission for connecting telephones to modems and are not also used for connecting them to the internet connection. They also have different types like RJ11s and RJ11w.
RJ14 or registered jack 14 is also known as two-wire connectors as they have two telephonic lines that can connect to two phones. They are 6P4C connectors with six pins and four contacts. They are commonly used in leased connections in the US. They are also used in US-manufactured modems.
Comparison Table Between RJ11 and RJ14
| Parameters of Comparison | RJ11 | RJ14 |
| Pins and contacts | Six pins and two contacts | Six pins and four contacts |
| Connectors | 6P2C or 6P4C | 6P4C |
| Alignment of wires | The negative wire goes to pin 3 and the positive wire goes to pin 4 | The negative wire goes to pin 2 and the positive wire goes to pin 5 |
| Number of wires | Two wires | Four wires |
| Accommodation | Accommodates one phone | Can accommodate two phones |
What is RJ11?
RJ11 is a registered jack that is commonly used for connecting phones to the modem or internet. They are 6P2C connectors but if the outer connectors are left unconnected then they can also be used as 6P4C connectors like in the case of RJ14.
They are the most popular and common type of registered jacks. They used in houses and offices where the old telephone wire connections are still in use. These jacks also have different types and are often indicated with suffixes like letters.
The suffix to RJ11 like RJ11s, RJ11c or RJ11w often indicates that there is an additional function to the originally registered jack. The suffix w in RJ11w indicates that these are the jacks that can be used if the telephone wire is to hang from the wall. The suffix c in RJ11c is for the jack that is used for desktop connections.
The two-wire type RJ11 that have 6P4C connectors are used for telephone handset services whereas the three-wire type RJ11 that have 6P6C is used for the wall hanging telephone services.
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What is RJ14?
RJ14 is also a registered jack that was found from the RJ11 but is more advanced than that series of a registered jack.
They are commonly used for connecting modems that are US generated or for lease connections.
These are designed such that they can accommodate more telephone lines so they are 6P4C connectors with six pins and four contacts.
Like all circuits to be complete, there are positive and negative terminals for RJ14 as well. The negative wire is connected to pin 2 and the positive wire is connected to pin 5 to complete the circuit.
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Main Differences Between RJ11 and RJ14
- The main difference between the two is the number of pins and contacts they have. RJ11 has six pins and two contacts whereas RJ14 has six pins and four contacts.
- Since they have six pins and four contacts, RJ14 is 6P4C connector. If the outer contacts of an RJ11 are left unconnected, they can act as 6P4C connectors but otherwise, they are 6P2C connector.
- Every circuit needs to have negative and positive wires. In the case of RJ11, the central wires act as the terminal wires with the negative wire going to pin 3 and the positive wire going to pin 4. But in the case of RJ14, the positive wire connects to pin 2 and the negative wire connects to pin 5.
- RJ14 has two wires whereas the RJ14 has four wires.
- These registered jacks accommodate phones depending on the number of telephonic lines and the wires that can be connected. So, RJ11 can accommodate only one phone whereas an RJ14 can accommodate two phones.
Conclusion
RJ that is short for ‘Registered Jacks’ that defines a series of telephonic connectors for common usage. They were first introduced by the US Federal Communication Commissions who had ordered Bell Systems to get this in order. These RJs were published such that each had different serial numbers.
RJ11 or registered jack 11 is also commonly called modem port and phone connectors. They are 4 or 6 contacts connectors for modems of computers in the US. It is generally used for connecting the internet to the phone or to connect the phone to a PC.
RJ14 or registered jack 14 is another type of connector with six pins and four contacts. Since they have two telephone lines, they can connect up to two phones. This is also why they are commonly called as two-wire connectors. They are often found to be used in leased connection in the US.
Though they are both registered jacks found for the same purpose of connecting phones and they do have telephonic lines, they are still different. RJ11 has six pins and two connectors whereas the RJ14 has six pins and four connectors. If the connections are made in a specific way then the RJ11 can be used as a 6P4C like RJ14.
References
- https://www.tandfonline.com/doi/abs/10.1080/14623943.2015.1064379
- https://core.ac.uk/download/pdf/159180559.pdf
Last update on 2022-04-01 / Amazon Affiliate links / Images from Amazon Product Advertising API