telephone wiring problem

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First some background. Several months ago the phones in our house went out. I figured out that it was a wiring problem inside the house. I called the phone guy to fix it. He said that our phone jacks are in series on two four-conductor cables. He said that there was a short. At one of the phones (it must have been between two of the phones), he switched to the other pair of conductors. He said that if we had this problem again that we would lose the use of one of the jacks, I think it was at the end of the line.
Recently our phones went out again, and rather than another expensive call to the phone company, I decided to try to fix it myself, thinking that it might be a similar problem. I disconnected the wires to one of the jacks he had worked on, and most of the jacks started working again. Only three jacks don't work - the one where I made the disconnection and two more on that end of the house. One of those two is apparently the end of the line, since only one cable is leading to it (the other two jacks have two cables).
I need to get one or two of the jacks on that end of the house working again, if I can. The problem is that I can't tell which cable is in or out. And if there is a pair of live conductors on the in cable. The only equipment is a volt/ohm meter. Is there a voltage across working conductors? If so, what should the voltage be and is it AC or DC?
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Jud McCranie wrote:

You should see a dc voltage across a live pair. Anywhere from 15 to 50 volts.
Jeff
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Jeffry Wisnia
(W1BSV + Brass Rat \'57 EE)
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On Wed, 15 Nov 2006 21:57:13 -0500, Jeff Wisnia

I can measure 50VDC on my phoneline, plus about 75VAC when the phone rings.

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On Wed, 15 Nov 2006 21:57:13 -0500, Jeff Wisnia

Thanks, that enabled me to fix it. Most of the pairs didn't give any reliable reading but then I found a pair with about 6 volts. I wondered if that could be it. I kept checking until I found one with 53 volts, and used that, got it back. Thanks!
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Jud McCranie wrote:

little gold-plated connectors in the jacks are corroded. My whole house went dead a few years ago, and I found that the installer(s) put the wall jacks in with the gold connectors on the down side of the jacks. One of the jacks which was on an outside wall had accumulated enough condensation on a hot, muggy summer day to short the connection with a few drops of condensate and eventually, it corroded the contacts. If they had installed the jacks with the contacts up and the release tab down, it probably never would have happened. My point is, check every jack internally to see if there is any corrosion or moisture causing your problem
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Good advice.

This is a common cause for trouble but usually takes YEARS to accumulated enough crud to affect service. The offending outlet is usually on an exterior wall, below grade. I have found such bad jacks behind aquariums, live plants and under windows. (potential moisture source)

Awesome! After all these years, yours is the first GOOD reason I've ever heard for installing phone jacks properly! I had never considered your reason.
On the other hand, I have replaced countless corroded jacks, properly installed, that I suspect inverse orientation would have had little effect.

More good advice.
The OP's home is wired in a "loop" configuration. That is, a SINGLE run of cable is LOOPED through each outlet (in-then-out). Of course, at the end is what appears to be a SINGLE cable - the "dead" end.
Obviously (to many, I suspect), if the pair is opened at any point in the cable, all outlets BEYOND the open will quit working. A short or other defect ANYWHERE in the pair will affect ALL equipment on that line until the defect is eliminated.
If the OP cannot find the defect and has only ONE phone line, he can switch to the spare pair (yellow/black?) immediately ahead of the defect and move all affected outlets to that pair to reactivate them. Good luck!
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On Thu, 16 Nov 2006 07:25:16 -0600, Jim Redelfs

I got the jack that matters working again, the kitchen wall phone. The other two jacks are downline from that, but I didn't bother getting them working since we haven't been using them anyway. If we decided to try to use one of them, I know what to try.
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One more question: does it matter if the positive voltage goes to the red or green wire in the jack? Can it go either way, or is there a certain way it should go?
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On Fri, 17 Nov 2006 10:23:03 -0500, Jud McCranie

I checked my phone line where it comes into the house, and found positive on green. I think that's the "right" way to do it.
Most electronic phones have internal rectifiers, so they don't care. Some early tone phones do care. Do you have one of those?
I'd do it right, if possible. Someone might want to use one of those old phones someday.

1. I choose not to remind people of inappropriately replying by email. This is not email.
2. The correct sig separator line is "-- ". Some newsreaders respond properly to that.
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On Fri, 17 Nov 2006 11:55:57 -0600, Mark Lloyd

After I wrote the message, I realized that the two active wires were a white/blue pair, even though I had to strip one of them. I put the white/blue stripe to green, which a website says is standard.

I have a recent electronic one, so it probably doesn't care.

I didn't know that, and I corrected it. -- Replace you know what by j to email
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With a white/green pair, it's right. With the older "standard" red/green pair, the RED is the correct conductor for voltage.
Solid/good continuity to ground with no voltage should occupy the "tip" conductor. (green of a red/green pair or white of a white/blue)
The "ring" conductor should have -48-52VDC-to-ground on it. You'll notice I said NEGATIVE 48VDC. Everything in the C.O. battery room is labeled as NEGATIVE. You tell me. <sigh>

Originally called a "polarity guard" when first introduced, you are correct.

Good advise, always.

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That is [hyphen] [hyphen] [space] [return] by itself at the beginning of a new line. That line and everything that follows should NOT be copied/quoted when using the quote function of a "compliant" newsreader.

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Tomorrow we will discuss lower-ASCII artwork. Class dismissed. <big grin>
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Jim Redelfs wrote:

Corrosion and oxidation are less likely to occur on lines that are negative to ground than positive. Hence, outside telephone plant is positive ground.
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Thank-you. It's probably basic electricity but I don't recall ever knowing that.
What in incredibly OLD technology. What other, equally old technology do we use so massively, on a continuous basis? Electricity? The internal combustion engine?
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JR

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Probably not. Only the very old Western Electric Touchtone<tm> sets required proper polarity. If the polarity is reversed, these increasingly scarce telephones can receive calls and be talked on but their keys will not sound when depressed.

Color to color is the proper technique.
If the pair's polarity is reversed somewhere in the line before it enters the premise, you can correct the polarity at the interface. All wiring beyond should conform to the standard: green/red or white/blue should go to the greed/red terminals on the jack. Black/yellow or white/orange should go to the black/yellow terminals.
If connecting a block at a tap point (a loop in a loop-wired installation) be sure to also splice the pairs "through". IOW, make a three-way connection to the pair at the location to feed that jack, making sure to splice-through extra/unused matching pairs.
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JR

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On Sat, 18 Nov 2006 09:21:58 -0600, Jim Redelfs

OK, but I don't understand what you mean by a three-way connection. The jack I got working was inside the loop. The blue/white pair of conductors to the red/green of the jack got it working. For the time being, I didn't try to get the next jack downline working, since we don't use it. So how should the 3-way connection be? -- Replace you know what by j to email
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If you don't want the stuff "downstream" to work, or there is trouble on the pair beyond that location, your connection at that location is known as a "dead end", not a three-way. If you don't "connect through" the conductors of the loop, you are "dedicating" the pair at that point. This is basic cable splicing and applies to much common electrical wiring as well as telephony.
If you DO connect all like (matching) conductors, you are making a "tap" or "three-way" (in-jack-out) connection. This is often done by placing BOTH like-colored conductors behind the appropriate terminal screw of the device (jack). Twisting them before placing behind the washer is poor technique. Placing individual "hooks" of tinned conductor, each behind its own washer, then slightly expanding/loosening/opening the hook before seating the screw, is next-to-best. The best tap technique, from a reliability and ease of trouble shooting standpoint is to connect a short length (8-12-inches) of wire to the jack - a "stub". Then, using two jellied 3-conductor, solderless connectors (Scotchlok<tm>), cut-in/splice-in the stub to the loop - a three-way connection.
A loop-wired home is probably the most confusing component to a DIYer doing some of their first phone wiring work.
It is a VERY primitive scheme: If the house just disappeared, you would have one, LONG length of cable. What appears to be two cables in an outlet box (or plaster ring) is really just a LOOP of that ONE cable, the bulk of which is permanently behind the walls and ceilings of the premise. Jacks are merely TAPPED onto a SINGLE pair in that single cable at several points along the cable. Lengths of cable can be tapped, or three-wayed, onto the main cable at any point to serve one or more outlets.
After THIS class <big grin>, you'll want to attend my next one where we'll cover the installation of a DPST switch that silences every station on the teenline until the kids' homework and piano practicing are done. That can be done from an SNID but having the switch mounted on the kitchen wall is the most convenient.
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JR

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On Sat, 18 Nov 2006 11:00:10 -0600, Jim Redelfs

That reminds me of the "ring control"cords" I've used in the past. These consist of a DPDT switch and a full-wave rectifier. When only DC is passed to the phone it works but won't ring.
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Mark Lloyd
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I hired-on as one of Omaha's first, male long distance operators with the old Northwestern Bell Telephone Company. Affirmative Action was 4-months old.
The job was right out of The History Channel: 20-30 of us, elbow-to-elbow, on non-padded (wicker seat) chairs plugging cords into jacks on a half-block long, black switchboard. I began wearing the "modern" (Mercury 7 era) headset. It was eventually replaced by a Plantronics "Starset".
It was a trip. After several INCREDIBLY boring months of this, I amazed all the women that had been plugging-away for 30 years, and had never seen such a thing, by drawing an half-inch long ARC by leaning on the ringing key and using another cord as the ground. Ahhhhh, the good, old days...
TeleTrivia: Although the first telephone operators were men, they were eventually replaced by women because women were less likely to swear at the customers or whittle on the switchboard.
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JR

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On Sat, 18 Nov 2006 11:00:10 -0600, Jim Redelfs

OK, I think I understand that now. I thought that a 3-way might be two wires going in and one the same and one different going out.

In our case we have two cables, according to the phone guy.
See if this sig is OK, I added a space after the dashes.
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That did the trick!
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