Help me wire my telephone line.

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Waper
New Member
Posts: 3
Joined: Sat Jul 15, 2006 7:40 pm
Location: Alexandria, Egypt

Help me wire my telephone line.

Post by Waper »

Hello,

I'm confused about how to wire my telephone line, I read a lot about this subject but information from some sources doesn't match with information from other sources, so I wonder which is right. Please advice. Thank you in advance.

Okay, starting from the NID/Demarc there comes two wires:

Red=Ring= -ve
Green=Tip= +ve

The confusion is about how to wire the telephone jack at house, some sources claims the following:

If you're looking at a telephone female jack, the pin assignment is as following

-----------------------
|...|...|...|...|...|...|...|
|...1...2...3...4...5...6...|
|...T...T...R...T...R..R...|
|...+...+...-...+...-...-...|
|____..................____|
........|................|
........|__..........__|
...........|.........|
...........|______|

Pin 1/6 = Line 3
Pin 2/5 = Line 2
Pin 3/4 = Line 1

Only pins 3 and 4 will be used since we have a single line only. So from this I gather that I should wire the Ring from NID to pin 3 and the Tip from NID to pin 4!

All phone jacks I purchased confirm this, but my xDSL splitter and all xDSL filters are in contradiction with the above information and states the following:

-----------------------
|...|...|...|...|...|...|...|
|...1...2...3...4...5...6...|
|...R...R...T...R...T...T...|
|...-...-...+...-...+...+...|
|____..................____|
........|................|
........|__.........__|
...........|.........|
...........|______|

Pin 1/6 = Line 3
Pin 2/5 = Line 2
Pin 3/4 = Line 1

So according to the above diagram pin 3 becomes Tip and pin 4 is the Ring!

Another issue is the male telephone plug, I think the colors should match with the female jack? But if I plug the xDSL filter the green connects to red and the red connects to green!

Which is right and which is wrong? Why the contradiction? Is this about using a straight cable from jack to phone versus using a rollover cable thus the crossed-over pins or what? :)

Please help, thank you.
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Far-N-Wide
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Posts: 1160
Joined: Wed Jan 26, 2000 12:00 am
Location: His Tavern of Solitude

Post by Far-N-Wide »

Polarity can be rolled. Your equipment will sense the inverted levels and internally correct polarities. As long as the pairs are consistent with the data paths, IE: 3 & 4 on the jack connect to 3 & 4 on the plug, your good. Same for 2 & 5 jack to plug. 1 & 6 are not used (that I know of) in standard 4 wire DSL applications.

There is a chart on this link... http://en.wikipedia.org/wiki/RJ-11 ,that lists U.S. wire color standards. It may better explain what I tried to. I was looking for the chart... not the verbage.

Cheers
USAFRETIRED
Waper
New Member
Posts: 3
Joined: Sat Jul 15, 2006 7:40 pm
Location: Alexandria, Egypt

Post by Waper »

Thank you Far-N-Wide :)

I already knew it doesn't matter which pair goes where as long as it is kept the same with the rest of the house installation, much like in electricity, most people don't care which is live wire and which is neutral.

Although it will work and you may never feel any difference, you will still have a non-standard installation which doesn't comply with NEC codes (for electricity) and with USOC (for telephone). Problems may arise in the future when you want to do an upgrade or maintain your installation. When I pick up a wire at the far end of my house after 20 years I would like to know what is it for without having to retest everything. There is also the possibility or certain devices which are polarity sensitive (0.01%).

Well, I know it's a matter of opinion. Anyway, thanks for pointing out the link to Wikipedia, the chart there is the same as the first one I posted, this is how I always knew it to be, I just got confused when I looked at my DSL splitter and noticed that they have reversed polarity, and to make things more confusing I looked at my DSL filters --they come from a different manufacturer-- and noticed that the colors are reversed at the plug. This made me wonder so I posted here and wished someone would tell me why that splitter and those filters don't follow the regular code.

Yesterday I sent an email to the DSL splitter manufacturer technical support asking them about the reason why their jacks aren't standard and I'm still waiting for a reply.

Thank you again Far-N-Wide :)

Best regards.
jim1133
Member
Posts: 25
Joined: Tue Jan 30, 2001 12:00 am
Location: Lexington, MA

Post by jim1133 »

I had DSL years ago (2000-2002) and don't think polarity makes any difference. I was surprised to learn that DSL worked on just a half a pair. My line was one side open in the outside cable. The phone didn't work, but DSL still ran like always. Don't recall whether it was the ring or the tip side which was open.

You could experiment by opening off one side of the inside wire at the splitter.
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