View Full Version : Testing or finding a phone wire

02-03-2006, 08:30 AM
Every room in our new house is wired for phone, but none of its connected.

At 5 of the outlet boxes (placed in the normal areas) there is a separate phone wire that is active.

Of course, one of the rooms where I need a phone line has the wire that isn't hooked up.

I know where all this wire bottoms out(in the basement) and I am smart enough to hook it up at the box along with the live phone lines.

My question is, its a ALOT of phone wire.

How can I test the wire to see which line I need without having to hook each one a get a dial tone.

I have a thingy that lights up when there is any power, so I will know when its right, but how do I get power to go through the line to make it work? Hook a battery?? Do I have to just experiment and hook em all up at one a time and find out?

I am talking about at least 11 outlet boxes that are wired that are not connect.

And all the wire is the same color. (except that ones that are duped and live)

How to do it?

[This message has been edited by cuemaker (edited 02-03-2006).]

02-03-2006, 09:00 AM
Q-maker each cable tan colored has two pair of leads... should be green, white, yellow, black and red if I remember correctly. If you only have one incomming phone line look at your junction box only two pair will be hooked up. If at the wall just open a working jack and copy the hook up there... at that end all lead will be terminated. Pairs should be yellow/white and red/black least that's how mine are paired for both incoming phone lines.

Hope this helps

02-03-2006, 09:00 AM
I find it, with a triplett fox and hound. You hook a rf emitter to the cable, then take the reciever and find the emitting cable, then confirm with telephone *homemade, or meter by shorting it and clearing it on the other end.

They have gotten much cheaper since I paid $300 for my set of tracers. I think About $50. But if you don't do a lot of electrical work, they are not worth that. The newer ones you can search out circuits while they are hot with voltage, not this one.

You can hook a 9volt battery to one end, and search out the voltage on the other ends.

02-03-2006, 09:12 AM
I'm not sure I understand your layout, but...

There are a couple of options. There's a test setup called a "fox and hound" sold by places like Contact East (no affiliation). You clip one side on to a pair of wires and it injects a signal. The "hound" part is a little thing with a pointer on it, and it helps find the pair of wires with the signal. I've seen it used by guys trying to find one pair of wires in the middle of a 3" diameter bundle of similar wires, and it seems to work. Now, I don't know offhand what a set costs, but a cheaper option would be....

Take a resistor of about 10K ohms and short it across the line in the room where you want phone. Measure the other end with an ohmmeter until you find the pair with roughly 10K ohms across it. If you get a phone, it'll be either 600 or 150 ohms, (on or off-hook, IIRC) and if it's not connected, you'll get more than 10K. There shouldn't be anything else connected that'll give you about 10K ohms, so that should do it.

The idea of a battery is a good one, too. Measure across the wires in the room with a voltmeter to make sure it's not "live". (A live phone line will measure around 50Vdc if it's not "ringing", or being "called") Wrap the pair around the terminals of a good 9v battery and go back to the junction box and find the 9v.

02-03-2006, 09:29 AM
Have you tried contacting the NSA? They have ways of finding phone connections.

Frank T
02-03-2006, 09:36 AM
Take a look in McMaster-Carr (on line) page 1718.

The standard "tone generator" is what you need.

Besides phone wires, I use it for all wire tracing.

They sell these at Home Depot and Electric Supply Houses.

Good Luck

02-03-2006, 12:22 PM
Yeah, the NSA has it covered!!!

Actually, I realize my post was horribly confusing. Thank you for trying to read through it.

Here is the simple question. phone wire in room. Phone wires (all of em) end in basement, not attached.

Need to find in mess of phone wires in basement the one that go to room so I can hook it up.

So the 9volt will send enough juice to trigger my little prob thing that lights up when there is electricity?

02-03-2006, 12:56 PM
Just touch each pair of wires to your tounge. You'll find it. Try not to taste an actual live phone wire though. http://bbs.homeshopmachinist.net//biggrin.gif

02-03-2006, 01:02 PM
would this work?
go to the socket you want to use and connect 2 wires with a paperclip or wire accross the pins. go to the other end in the basement and check for continuity with a multimeter set to "buzz"

02-03-2006, 01:23 PM
Ok, this is the thing, all these wires are not hooked up to anything.

It seems like that prewired everything. Then ran more wires, (this time to only a few rooms) and hooked up this 2nd set of wire that are live.

The ones I want to hook up just prewired. Thats it

Its only this 2nd set lines (which DO NOT go to the room I need it to) that are connect to the phone.

02-03-2006, 01:29 PM
Evan: the ringing voltage will make you pee your pants.

I can't imagine explaining the blister on your tongue.

mike thomas
02-03-2006, 01:47 PM
There are several ways to do this. One, wire the jack, plug in the phone and take it off hook. Check the wires on the other end for a short.
Two, put the VOM on the wire you want to hook up. Short the wires in the basement one at a time until some one upstairs shout that they see the short on the VOM.
Three, set the phone and jack up as in one, go battery to ground with the VOM and watch the voltage with the VOM as you touch the wires to heat up. When the voltage drops about 50%, that is the one with the phone off hook.
Four, short the wire upstairs and touch the wires to the heat up one at a time until someone on another phone tells you the line went dead.
There are about another 50 ways to do this, but one of these should suffice.
If the jack is not a home run, but daisy chained through other outlets, tie common colors together in each outlet box.

3 Phase Lightbulb
02-03-2006, 02:01 PM
Here is another method:

-Plug in a phone jack pig-tail into the phone jack. Place both pig-tail leads in a coffee mug filled half-way with Full Throttle.

-Go downstairs with a volt meter. Set the meter for ">1KV" and measure each unconnected pair of wires until you find the pair that has approx 1500v.


02-03-2006, 03:02 PM
Ya know, that full throttle stuff didnt do a darn thing for me.

I will give it a 2nd try

3 Phase Lightbulb
02-03-2006, 03:08 PM
<font face="Verdana, Arial" size="2">Originally posted by cuemaker:
Ya know, that full throttle stuff didnt do a darn thing for me.

I will give it a 2nd try</font>

Full throttle is only fuel...

What kind of engine are you putting it into? http://bbs.homeshopmachinist.net//wink.gif

02-03-2006, 03:17 PM
Run a new set to the location you want to hook up at. if you have that much extra wire installed you should pull everything youare not using out to keep it simple.

Been there, probally broke it doing that

02-03-2006, 04:23 PM
True, jet fuel to slug is nothing more than annoyance.

As for running new wire, Its from the 2nd floor to the basement. I really doubt that i would get it pulled through.

Although if the line would move, I could pull it from the room and then see the result in the basement

02-03-2006, 05:23 PM
<font face="Verdana, Arial" size="2">Originally posted by bolmas:
would this work?
go to the socket you want to use and connect 2 wires with a paperclip or wire accross the pins. go to the other end in the basement and check for continuity with a multimeter set to "buzz"</font>

This could work unless you stumble across a wire that the installer stapled a little too aggressively. It will also show as a short - this happened to me in my previous abode. That's why I suggest something other than dead-short or open, or what might look like a telephone.

For that many wires, and considering the likelihood that this will come up again, maybe the fox-and-hound are the best solution for cue.


02-05-2006, 04:20 AM
If you have a tone generator and inductive amplifier, thats the easy way.

You can also use an audible continuity tester to buzz out the wires.
Connect the continuity tester to a pair of wires in the room you want to connect.
Go to the basement and short out the same color pair on each cable until you hear the tester.
If you don't have an audible continuity tester, a simple battery and light bulb, and a helper to yell when it lights up will do the job.