Phone cabling has come a long way from when the telephone was first introduced. What used to be cloth-covered wires that ran from your house to a building staffed with operators that physically connected your calls on a switchboard to the tone-coded dialling we have today, the actual wiring used has gone through a number of changes.
The Evolution of Phone Cabling
Phone cabling started out as a single pair of very brittle wires that ran between your house, if you were lucky enough to have a phone, and a central station, where the operator made the physical connection between your phone and the phone of who you were calling, by inserting a ¼ inch plug into a socket that was connected to the phone cabling going to your house. The next step in phone cabling evolution was the wire bundle. This was usually either three or four pairs of wires loosely twisted together inside the house, connected to a Network Interface Device that connected you to the wiring to the central office. This loose bundle of wires looped throughout the house and connected to screw terminals. Next came Category 3, 4, 5 and now 6 cables. This type of phone cabling consists of an external insulator containing eight conductors combined into four separate colour-coded tip and ring pairs.
Types of Phone Cabling Terminations
There are two main types of phone cabling connectors in use these days. These are the RJ-11 (four wire) and the RJ-45 (eight wire) plugs. Most people are familiar with the RJ-11 plug and jack that normally have two copper connectors. The RJ-45 is the same type of connector that you use to connect your computer to the router for internet service. Phone connectors have evolved from hard-wiring the phone to the phone cabling to a variety of connectors. The most common type of second-generation connector is connected to the phone cabling by screw terminals and to the phones with a jumper cable with RJ-45’s at both ends. If the phone cabling was a single loop in the house, you would remove some insulator from a pair of wires and wrap the bare portion around the screw terminals and tighten the terminals, allowing the conductors to complete their loop without breaking the wire. This allowed multiple phones on the same line. Nowadays, most phone jacks have all four pairs of the phone cabling routed to them and each phone jack has its own cable. The pairs that are used determine the phone number. The terminations on this type of jack are what are known as insulation displacement connectors, where the wire is inserted into the connector using a punch down tool, and two metal blades puncture the insulation and make contact with the conductor.
Points That Make-up a Professional Phone Cabling Installation
Almost anybody can run phone cabling from point A to point B and make connections. Lots of small details can mean the difference between a quality phone cabling installation job and a sloppy one. From the end-user’s standpoint, the jacks have to be inconspicuous yet easily accessible. Jacks and faceplate colours have to match and not detract from the décor of the room. Phone cabling needs to be properly supported and, when run in accessible areas, properly protected from damage. This may mean supporting the cabling in hooks in an attic or basement, or routing the cables in the corners out of the way. Connections have to be properly made and polarity must be the same at both ends. When there are two jacks servicing two different phone numbers, or lines, they should be differentiated somehow, usually by colour. Extension numbers or phone numbers should be noted on the jacks or faceplates.
What the Future Holds
The next two types of phone cabling coming to the house are going to filter-tipped and Category 7 twisted pair. With fibre optic phone cabling, you’re going to get TV, phone and internet, all high speed, in either a pair of fibre optic single-mode cable or a single multi-mode fibre optic cable, from a single company, instead of as many as three. The new type of phone cabling that will be used inside the house is going to be Category 7 twisted pair. These will continue to be connected via jacks, with jumper cables to make the physical connection to the phones, however, as your home phones are upgraded to video capability, they may use two pairs instead of one.
There may be people that remember party lines and having to talk to an operator to call your friend three houses down. As the equipment that runs the phones in your house has improved, the phone cabling to and in your house has also improved to keep up and deliver new services and capabilities.