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View Full Version : 1 phone, dial tone; 2 phones, no dial tone


Chuck Bradley
January 14th, 2004, 07:54 PM
I'm new here, so I appologize for any bad manners.

I have one main question, and several more in the background section.

I get a dial tone in the kitchen, but it goes away when I add the
second floor bedrooms. Why, and what can I do about it?

Of course you are suspicious about my question. Why do I mention
adding the other portions of the house? The background info will
supply the answers, I hope.

The house was built in 1977. We are the original owners. Until this
weekend, the phone wiring was never touched. A few covers were removed
for painting or wallpapering projects, but none for several years.
No wires were ever added or removed.

There are extensions to the system in several rooms, all by extending
existing RJ11 cables with connectors or Y adapters. From the jack in
the kitchen, there are drops in several rooms to hook up a computer.
One bedroom upstairs has drops for three computers. All of this
stuff has worked for months, and most has worked for years.
Almost all of the added stuff is unpluged now. All of the phones
and computers are disconnected. A few jacks are behind bookcases, so
there is a cable in the jack, and nothing at the other end of the cable.

I knew almost nothing about the phone system. There is a network interface
device. Test there. The problem is probably in your house. If you have
anything other than a plain old telephone plugged in to the phone network,
unplug it before beginning to do any diagnosis or repair. I still know
almost nothing about the phone system. I'll probably get some of the
terminology right because I spent a day at the local library and most of another
day on the web. My new knowledge is suspect. I probably got some of it wrong.

Perhaps information about me will help identify my blind spots or mistakes.
I programmed digital computers for over 40 years, got instructions added
to the instruction set, rebuilt carbs, transmissions, DOHC engines, cut
and split several cords of firewood per year, and do almost all home maintenance,
but I still know almost nothing about the phone system, even if it sounds
like I know a little bit.

We lost dial tone over the weekend. We are having some cold weather here
near Boston. I unplugged everything and dial tone came back. The next day
dial tone disappeared again. This time, unplugging everything did not help.
We had one warm day after that, but a problem persists. Details are below.

I traced wires and found a three pair cable goes from the network interface
to the kitchen and continues upstairs to four bedroom jacks. I learned
two color wires are identified by the dominant color first. The green and
white/green pair was unattached at the NID and continued through the kitchen box.
The box in the kitchen contained what I learned was a split beam strip without
connector caps. The orange and white/orange pair from outside terminated at
2 and 1 respectively. The blue and white/blue pair ended in air.
The orange and white/orange wires to upstairs hung in the air. The blue and
white/blue wires went upstairs from terminals 2 and 1 respectively.

The symptom, no dial tone from any jack could be explained by a fault in the
cable from the kitchen to the NID or by a fault in the split beam strip.
The change in color and some history of the house led me to suspect the cable.
The local hardware store had the classic four wire, red green, black, yellow
cable. I installed it from the external world to the box in the kitchen and
still had no dial tone. So perhaps my guess was wrong. I bought a new plate, with screw terminals and replaced the junction in the kitchen. Success. Dial tone.
Computers can connect to the Internet from the external cables that originate
at the jack in the kitchen. We can make and receive calls.

When I try to reattach the second floor, things fail. Usually when I expect a
dial tone, I get almost silence, but not quite silence. Rather it is the very
faint sound of voices, perhaps cross talk. I can not make out words. Sometimes
I suspect the words are the canned hang up and try again message, but this
happens before any dialing, and immediately after going off hook.

Sometimes I get a shrill beeping, about the frequency of a busy signal.
I don't know what I'm doing differently to get different results.
What could cause the beeping?

I thought I learned that white/blue is tip, the same as green, and
blue (when paired with white/blue) is ring, the same as red.
But properly paired, or improperly paired, the dial tone goes away
when I reattach the second floor to the network. Why?

My wife noticed a phone company car in the neighborhood. Is it possible
my efforts affected other people? I thought the NID prevented problems
from excaping from the house to the network. Does it?

I'm willing to collect additional information if that will help identify
the problem.

Thanks in advance for any help.

Chuck Bradley
January 15th, 2004, 12:17 PM
Here is some more information about the problem.

I pulled open one of the bedroom junction boxes.
Inside was a WE 625F with 4 screws and a RJ11 jack
with red, green, black, and yellow wires.
The house wiring came down from the attic and back up.
Connections to the screws were by a bare spot on the
continuous wire.

Green and white/green were not hooked up. Red from the
jack connected to blue of the house. Green connected to
white/blue. Black connected to orange. Yellow connected
to white/orange. That seemed compatible with what I
had observed in the kitchen.

I bought a simple phone line tester that seems to be
powered by the line. A green light means all is well.
A red light means reversed polarity. No light means
not working. At the jack in the kitchen I get green
light when the bedrooms are not connected and no light
when they are connected.

With the bedroms disconnected from the kitchen, I used a
splitter or Y in the kitchen, with a phone on one leg
and a long extension on the other. When I plugged the
cable into a jack in a bedroom, the dial tone went away.
With the tester in place of the phone, no light lit.

I discovered the red wire (ring) is supposed to be -48VDC
and green (tip) is supposed to be ground. Testing in the
kitchen with my cheap VOM I get the same results with
the bedrooms connected or not. Green is 0 V. Red is -50,
probably -48 within the accuracy of the meter.

mdshunk
January 15th, 2004, 05:08 PM
It it possible that in one of your RJ11 jacks, some of the terminals are sightly bent, so that when you insert the phone's mod plug in the jack, the terminals touch each other and short out? Just a possibility. Worth a look inside all of then with a flashlight.

mdshunk
January 15th, 2004, 05:16 PM
Afterthought, If you plug a splittler directly into the jack on the NID, and add one phone then the second phone, do you maintain dial tone? I was just trying to see if Ma Bell's line to your house could possibly be "drawing down" for some reason. With more and more pair gain equipment (SLIC Huts) being used by the phone company, loop current on the line is getting higher and higher, causing lots of weird problems such as you're experiencing. Could still be in your house wiring, but try plugging multiple phone sets directly into the NID to rule out Ma Bell as a source of the problem.

Chuck Bradley
January 15th, 2004, 08:13 PM
It it possible that in one of your RJ11 jacks, some of the terminals are sightly bent, so that when you insert the phone's mod plug in the jack, the terminals touch each other and short out? Just a possibility. Worth a look inside all of then with a flashlight.

Thanks for the idea. I'll take a look. The design of jack and plug appears
to make contact difficult, but some of the jacks were out shortly
before the failure, so I'll check and report back.

Chuck Bradley
January 15th, 2004, 08:34 PM
Afterthought, If you plug a splittler directly into the jack on the NID, and add one phone then the second phone, do you maintain dial tone? I was just trying to see if Ma Bell's line to your house could possibly be "drawing down" for some reason. With more and more pair gain equipment (SLIC Huts) being used by the phone company, loop current on the line is getting higher and higher, causing lots of weird problems such as you're experiencing. Could still be in your house wiring, but try plugging multiple phone sets directly into the NID to rule out Ma Bell as a source of the problem.

I can do this tomorrow and report back. I can do it even without knowing
about pair gain equipment and SLIC Huts. I'll look them up after reporting
back.

By the way, I hope I did not mislead with the title of the problem.
I lose the dial tone when I connect the bedroom jacks with the kitchen
jack, even if there is no phone in any of the bedroom jacks. The title
was the best I could do in the space available. I suspect I can change
the title, so any improvements are welcome.

I think I understand the idea you propose. I've got more than one
splitter, so I'll see how many phones I can connect at the NID.
Thanks for the suggestion.

Chuck Bradley
January 16th, 2004, 11:56 AM
I checked all the jacks and they all look fine. The contacts are
parallel to each other and evenly spaced.

I used two splitters so I could plug in two phones and my tester
at the NID. The tester showed OK, and I could get dial tone on
either phone.

With the jack at the NID occupied, the phone in the kitchen could
not get dial tone. I had not noticed that before, but it makes sense.
The NID has to protect the jack from the mistakes in the house wiring.

I finally realized I could make another measurement. In the kitchen,
with the bedrooms disconnected, the resistance between the tip and ring
wires to the bedrooms is infinite, a far as my cheap VOM can tell.

suemarkp
January 19th, 2004, 02:52 PM
I think your last test was the right idea. It sounds to me like you have a cabling problem in the wire from the kitchen to the upstairs. The resistance test was a good first step, and high resistance is what you want to see. If it was low, the phone signal would be shorted and kill all the phones.

Another test to try is to see if your bedroom cable has a short to ground. While it is disconnected from the kitchen jack, see if either bedroom wire has any resistance to a good ground. Resistance should be infinite.

Another test would be to disable the inside phones at the NID by removing the house phone RJ plug from the NID jack. Then connect the bedroom phone to the kitchen jack. Now measure the resistance between the phone lines inside the house. It should be infinite here too if no phones are plugged in. You may need to use a scrap of phone cable here so you have an RJ-11 jack on one end and bare wires on the other. Makes those big probes on the meter easier to connect without them shorting everything.

If all of these test pass, then I'm running out of ideas. You could try different pairs of wires if more are available. Are there other phone jacks in the house besides the kitchen and bedroom phone? If so, where do they connect from (daisy chain or home run to some other jack).

My phones died when I tucked a spare cable hanging from the basement ceiling up into the furnace ducting (I was cleaning up for the electrical inspector). The very end of the cable was touching the grounded ducting and took out all the phones. As soon as I narrowed it down to that cable, I realized what happened before actually seeing it.

Chuck Bradley
January 20th, 2004, 09:31 PM
I think your last test was the right idea. It sounds to me like you have a cabling problem in the wire from the kitchen to the upstairs. The resistance test was a good first step, and high resistance is what you want to see. If it was low, the phone signal would be shorted and kill all the phones.

Another test to try is to see if your bedroom cable has a short to ground. While it is disconnected from the kitchen jack, see if either bedroom wire has any resistance to a good ground. Resistance should be infinite.

Another test would be to disable the inside phones at the NID by removing the house phone RJ plug from the NID jack. Then connect the bedroom phone to the kitchen jack. Now measure the resistance between the phone lines inside the house. It should be infinite here too if no phones are plugged in. You may need to use a scrap of phone cable here so you have an RJ-11 jack on one end and bare wires on the other. Makes those big probes on the meter easier to connect without them shorting everything.

If all of these test pass, then I'm running out of ideas. You could try different pairs of wires if more are available. Are there other phone jacks in the house besides the kitchen and bedroom phone? If so, where do they connect from (daisy chain or home run to some other jack).

My phones died when I tucked a spare cable hanging from the basement ceiling up into the furnace ducting (I was cleaning up for the electrical inspector). The very end of the cable was touching the grounded ducting and took out all the phones. As soon as I narrowed it down to that cable, I realized what happened before actually seeing it.

Thanks. And sorry for the delay in saying so. I'd just about given up
hope of more suggestions so I was not back here as frequently as I
should have been.

I'll check resistance to ground at the bedroom box I have open.
I'll also check at the other bedroom jacks. There are four bedroom
jacks on the second floor. They are all in interior walls, fairly close
to a jack on the other side of the wall. I have not found any junction
box, but the wiring I can see from the kitchen and the open box upstairs, makes me think I have pure daisy chain: NID, basement, kitchen,
BR1, BR2, attic, BR3, BR4. The layout of the house makes me think the
box I have open is in BR3.

The similar check at the NID is actually easy. There is a jack, but the
connection to the house wiring is by posts and nuts.

I'll try the tests tomorrow and report back.

Thanks again.

Unregistered
January 21st, 2004, 10:03 PM
The cable goes NID, kitchen, BR1, BR2, BR3,BR4.
I cut the cable at what I thought was BR2, but really was BR1.
I was hoping to cut the problem in half, isolating it to the
kitchen to BR1 to BR2 segment, or the BR2 to BR3 to BR4
segment. Anyway, good (infinite) resistance on the line to
BR2 and beyond. Hooked up kitchen to BR1 line at both ends.
Dial tone in kitchen and BR1. Progress.

Next cut and connections at BR3. Good resistance forward to BR4.
Dialtone in BR1, 2, 3, and kitchen. More progress.
BR4 is my study, with 3 computers. The cable that runs behind
four bookcases and two filing cabinets and had not been touched
for over a year, was bad. I can see frayed wire near the connector.
Replacing it makes everything work. I still can not account for the
failure by my resistance, or any other, measurements, but this message
comes from a computer in BR4.

This adventure has given me confidence to install phone jacks
elsewhere if I think I need them.

This conference is now marked so I can browse here or help others or beg
for help on a new and unexpected problem.

Thanks.

mdshunk
January 23rd, 2004, 03:23 PM
Your troublesome adventure is exactly why "daisy chaining" phones is a really bad idea. Phone jacks should always be individually home run back to the NID. Daisy chaining was done for a long time, but causes too much trouble. Trouble in just one place will generally put all your phones out of commission. With home runs, troubleshooting is much easier. I guess I'm just trying to encourage you, that if you add stations, do it by home running the cable... it's certainly cheap enough stuff.