I have six (6) phone lines running from my rooms into the basement. They are not terminated as this is a new build. I need to determine which line corresponds to which room.

Is there a way to do this without purchasing a line tester?

  • 2
    I've never tried it but a 9 volt battery and a voltage detector. Maybe there will be enough juice to make it thru with the voltage drop. – lqlarry May 30 '12 at 4:45
  • They're still putting phone lines in houses? :) – DA01 May 30 '12 at 4:55
  • @DA01 not really, but I requested them (at no extra cost). I have some DIY automation stuff I expect to keep me busy for the next few years. – Alfero Chingono May 30 '12 at 20:31
  • @lqlarry - Thanks, the 9V battery really did the trick. It's amazing how simple old-fashioned solutions can save the day. You should've made yours an answer. – Alfero Chingono May 30 '12 at 20:33
  • Didn't know if it would do it so I didn't put it as an answer. I'm glad it worked and I hope I remember that the next time I'm stuck. – lqlarry May 31 '12 at 0:32

The simplest route would be to use a circuit tester on the various lines in your basement, and have a friend temporarily short the lines in each of the rooms.

An audible circuit tester makes this very easy. It can be a standalone circuit checker, or as part of a multimeter's functionality. It raises a voltage across a circuit, and if that circuit is complete current flows, sounding a buzzer.

If you have a multimeter, look for a speaker icon to see if yours can do this.

As @lqlarry said, you could do this with a 9V battery but that shouldn't be needed - the voltage drop should be negligible.

  • This answer could be a bit better if you explain a bit more, and instead of saying "circuit tester", explain how you're using a multimeter to check resistance. – gregmac May 30 '12 at 14:07
  • updated @gregmac. Betterer? – Rory Alsop May 30 '12 at 14:23
  • I took @lqlarry's idea and bought a 9V battery and a voltage tester. Total cost approximately $14. – Alfero Chingono May 30 '12 at 20:35

Well I think you know already that the typical way to find these is with a tone generator kit (line tester), however, the simpliest way is to simply plug a phone in to the end of the drop, and then connect the drops to the feed (patch panel/NID/etc) one by one until you hear a dial tone on the phone. When you hear the dial tone, you know what line you've connected. The step by step process works like this:

  1. Terminate the end where you will plug a phone in (install a jack).
  2. Plug a phone into the jack you just installed; verify there is no dial tone
  3. Head downstairs (or where ever all your wires are located). Pick any cable and connect the red/green pair to the live service (probably the red/green pair too)
  4. Go back to the phone - check for dial tone. If you have a dial tone, you know what cable it is. Now repeat for other phones.
  5. If you didn't hear a dial tone, disconnect the cable and try another, and repeat the process until you find which one it is.
  • Sorry, but you used a few big words there. If I plug a phone on one end, does the phone generate enough juice to test with a circuit tester? – Alfero Chingono May 30 '12 at 19:46
  • No, the idea is that you have a phone plugged into a dead line - no dial tone. Now hookup the wires one by one until you get a dialtone - now you know what wire it is. Will require lots of running around in the house, however – Steven May 30 '12 at 20:22
  • I've added more details to the post to hopefuly help! – Steven May 30 '12 at 20:27
  • Got it. However, I am not connecting the lines to the PSTN. I just need to connect two (2) of the six (6) lines to an ATA adapter. Didn't want to spent all that much to get all the lines terminated. – Alfero Chingono May 30 '12 at 20:38

I used a 9 volt battery and a multi-meter tester. Fist, I Hooked the solid blue wire to the positive post on the battery and then I attached the whitestripe/ blue wire to the negative post. Then I went down the basement where all the wires go into the phone box ( I had 10 wires hanging down there and none of them had been hooked up). I started testing the solid blue wire and whitestripe/ blue wires from each of the cat5 wires hanging down there in the basement with a multi tester. Suddenly the meter pegged and when it did this I knew that I had the wire that was attached to the 9 volt battery up stairs. This could be done alone as long as you can figure out how to attach the small little wires to the top of the 9 volt bettery. I was lucky to have a snap on plastic protector from one of my 9 volt batteries handy and used this to snap those little wires to the top of the battery. Not sure what the correct setting on the multi-meter tester was. Just google this part. When I googled it I someone said to to set the multi-meter to the DC setting and moving the selector to at least the 40 volt range. This seemed to work well for me. Good luck

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