San Diego Repair Finders

My phones are not working. I called the telephone company, and they claim that  the problem is inside my house. How can I find out what the problem is?

Lets go over the basics of telephone wiring. Once you understand the basics, troubleshooting becomes a breeze. It may be time consuming, but a breeze. And at $40 or more for a half hour's service from the telephone repair guy, the wind will be at your back!!

The really basic basics of telephone wiring...

Though you may have hundreds of feet of phone wire and countless connections, telephone wiring is really simple and logical. Take a walk around your house, and we'll figure it out together.

The telephone company, bless their souls, provides you with service through four wires or more wires leading to the outside of your house (there is actually more to it than that, but you don't need to know more to work on your own stuff). These wires connect to a box called a network interface, usually located outside your home for ease of access by the telephone company. It's also referred to as a protector (just the sound of it makes you tingle, eh?) The name "protector" is apt... it protects your house telephone wiring from unusual electrical surges from lightning strikes, power lines that may touch outside telephone cables, etc. Not a foolproof system, but very effective 99.9% of the time. The protector can often be found near your electrical service (meter), because the phone company and the electric company use the same criteria for choosing an access point to your home.

The network interface acts as your main junction box- the place where all telephone cables leading into your house originate. Usually, part of it is off limits to you. It may be sealed with a lock, or screwed shut. This is where the phone company makes its connections. The wiring colors will not correspond with the color coding of your interior telephone wires.

The customer-accessible side uses the standard color coding that you will run into again and again in all telephone work. Most common telephone cables have four wires inside... red, green, black and yellow.  In the trade they are referred to as "pairs".  The red-green pair is used for basic one line service, and the black-yellow pair is used to provide a second line.

If you look at the blowup of the network interface to the left, you will see that there is a "block" with six colored screws.  There are three pairs together... yellow-black, red-green and a second yellow-black.  You will also notice that there are wires connected to the red and green terminals.  In this connector, there is only one live telephone line... line 1.  Though the connector can carry up to three lines, for ease of customer use they usually only install one line per connector.  If you had three lines, you would have one connector serving one line, and the second connector serving two lines.  This network interface box has two such connectors, so this home could conceivably have up to six telephone lines installed. 

The actual connection to your wiring is made through the telephone jack in the connector by means of the removable plug attached to the black wire.  Disconnecting this plug disables the telephone lines attached to the connector.  This plug makes troubleshooting a little easier, since you can plug a tester into the jack to see if the telephone company's lines are okay (more later on troubleshooting).

Some older homes do not have easily accessible interfaces...

In older homes, the protector outside your home is a sealed box that does not allow customer access.  It contains a special fuse to stop lightning from reaching your inside wiring.  Essentially, it is a starting point for a standard 4-wire cable to enter the house, and you have no easy access to its innards!

Why was the phone company protective of its protector?  Part of the reason for this is that, years ago, the phone company did it all... they owned all the phones, the wires, and the jacks, and it was illegal for you to mess with the wiring. So they had no incentive to make direct access to the inside of the protector available to you. Hooking your phone cables directly to the protector is advantageous because the telephone signal is the strongest there, and I recommend it when and if possible. In fact, if you have an older style protector, many phone companies will replace it with a modern connector, such as pictured above, at no charge. Especially if you are having phone problems or Internet connection problems!! Just cry and beg like I did!

A second important reason why homeowners were denied access is because of the fear that they would connect wires to the unprotected side of the box, leaving their wiring systems vulnerable to lightning surges and the possibly disastrous consequences!

So if you have an old-style sealed protector, your access to the telephone company is via a run of cable (usually 4 wire, or two pair) that enters your house and is connected to a junction block or entrance bridge. Junction blocks are rectangular plates that use screws to connect each of the four service wires (from the phone co.) together with your inside wires. A junction block has four terminals that hold the wires together with screws.  The wires from the telephone company and your inside wires share a common screw based on the wire color... all reds to one terminal, blacks to another, etc.  This system was great when people maybe had two phones (if they were filthy rich), but get a little crowded with three or four pair running off them to multiple telephone jacks.

Historically, junction blocks originated when homes had just one  telephone line and one telephone.  A single wire entered the home and went to a single jack.  As years went by and people began wanting more convenient telephones, additional wires were run off the junction block to service other phones.  After about two connections, the blocks were jammed with wires and difficult to work with.  Enter the entrance bridge... a vast improvement.  Instead of having the telephone wires run to a junction block in the living area, the entrance bridge was installed in a basement or utility room.  Entrance bridges perform the same function as junction blocks, but the incoming telephone company wires do not directly touch your home's cable wires. Instead, they use various methods of securing the wires onto an insulated metal frame which provides the connection.  As you can see in the graphic, the telephone company's wires (entering the graphic from the bottom) each attach to a block with two screw terminals.  Up to two telephone lines with two separate cables (upstairs and downstairs, for example) could be attached without the necessity of wire-sharing on a terminal.

As you can see, entrance bridges can hold more wire connections than junction blocks, and since each connection is separate are your preferred choice for new or replacement installations.  You will have both a better electrical connection, less chance of wires inadvertently touching and less confusing wiring!

To summarize, two wires provide all your phone service if you have one line, four wires if you have two lines. And all of your wall phones, cordless phones, computer modems, answering machines, fax machines and even your remote home security system lead back to the phone company via these little wires.

If you don't want to risk making anything worse, contact our phone repair specialists in San Diego today at Repairfinders.com!