How does telephone cable work

When you compare that to the state of the world just years ago, when it might have taken several weeks to get a one-way written message to someone, you realize just how amazing the telephone is!

Surprisingly, a telephone is one of the simplest devices you have in your house. It is so simple because the telephone connection to your house has not changed in nearly a century. If you have an antique phone from the s, you could connect it to the wall jack in your house and it would work fine! In this article, we will look at the telephone device that you have in your house as well as the telephone network it connects to so you can make and receive calls.

See the next page to get started. That's it! You can dial this simple phone by rapidly tapping the hook switch -- all telephone switches still recognize " pulse dialing. The only problem with the phone shown above is that when you talk, you will hear your voice through the speaker. Most people find that annoying, so any "real" phone contains a device called a duplex coil or something functionally equivalent to block the sound of your own voice from reaching your ear. A modern telephone also includes a bell so it can ring and a touch-tone keypad and frequency generator.

A "real" phone looks like this. Still, it's pretty simple. In a modern phone there is an electronic microphone, amplifier and circuit to replace the carbon granules and loading coil. The mechanical bell is often replaced by a speaker and a circuit to generate a pleasant ringing tone. The telephone network starts in your house. A pair of copper wires runs from a box at the road to a box often called an entrance bridge at your house.

From there, the pair of wires is connected to each phone jack in your house usually using red and green wires. If your house has two phone lines, then two separate pairs of copper wires run from the road to your house. The second pair is usually colored yellow and black inside your house. See What do the little boxes that the phone company has around our neighborhood do?

Along the road runs a thick cable packed with or more copper pairs. Depending on where you are located, this thick cable will run directly to the phone company's switch in your area or it will run to a box about the size of a refrigerator that acts as a digital concentrator. The concentrator digitizes your voice at a sample rate of 8, samples per second and 8-bit resolution see How Analog and Digital Recording Works for information on digitizing sounds. It then combines your voice with dozens of others and sends them all down a single wire usually a coax cable or a fiber-optic cable to the phone company office.

Either way, your line connects into a line card at the switch so you can hear the dial tone when you pick up your phone. If you are calling someone connected to the same office, then the switch simply creates a loop between your phone and the phone of the person you called.

If it's a long-distance call, then your voice is digitized and combined with millions of other voices on the long-distance network. Your voice normally travels over a fiber-optic line to the office of the receiving party, but it may also be transmitted by satellite or by microwave towers. See How does a long-distance call work? Return to Telephone Troubleshooting articles. In a typical home, the telephone cables connecting your phones within you home contain four wires They are used in pairs for each phone line you have.

Repairmen in fact refer to the wires in terms of "pairs", so technically a standard four wire telephone line has two pairs. LINE 1 uses the red-green pair. Line 2 uses the yellow-black pair. IF you need to run more lines than just two, you may just want to use a 6-stand or higher. There are two types of common modular plugs; the RJ and RJ The most common is the RJ, which uses only two of the telephone wires in a four or more strand wire.

This is the same kind of plug that you use to plug your telephone into the wall: a 1-line plug. The first step to a small telephone wire job is to figure out what the phone company has left you to work with. What kind of network interface do you have? Most new installations consist of a network interface box.

This has modular test jacks where you can plug a phone in to see if the phone line is live and a terminal strip from which you run your internal telephone wire. From the network interface, you want to plan how you want the wiring in your location to be. The star or homerun method is the most common method of telephone wiring.

The other type of wiring is called the series or loop method. In this method 1-line telephone wire links all of the extensions in a series. The cable connection in the home or business transmits the phone signal. Cable broadband services contain adequate bandwidth to allow customers to talk on the telephone while using the Internet connection or watching cable TV. There should be no loss in performance if the system is installed correctly.

Existing cable customers adding VoIP services may find discounts available from their cable company. New cable customers will often find package discounts for bundling television, Internet and phone services that are installed and activated at the same time.