bit of telephone help

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JHZR2

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Hello,

My parents own a two-family house. For a while, they rented out part of it, then they lived in both parts, now they are going back to renting one part. When they lived in both halves, we set up the phone service so that one active service coming into the house (upstairs and downstairs have separate lines coming into the house) could be used in both halves.

The issue now is that they want to go back, and can't seem to figure out how. They need to reconnect things, but being a 90 year old house, the wiring isnt the most clear-cut or makes the most sense.

They have two devices that look like this:
phone-terminator.jpg


Assuming that the wires to the phone company still are connected into these boxes, they ought to each have a signal, right?

I assume that if we put a multimeter on an active phone pair from the telephone company, we will see 50VDC, correct?

So, end of all this, question is twofold - today, are devices like I pictured above still needed? What do they do? AND, given two pair of wires coming into a home, what is the easiest way to determine which are live?

Any insght would be great. Im trying to help them troubleshoot remotely, to save a 100 mile drive.

Thanks,

JMH
 
Quote:
are devices like I pictured above still needed?

Maybe not in the same form, but yes.

Quote:
What do they do?
It provides a common point of service. All "lines" should make (what is called) a "home run". You don't need a "home run" ..but that's how they wire it. You can bridge to any extension.


You have two of these in the basement or in an outside enclosure (given the age, a possibility). Now when your parents joined the two services, the phone technician either bridged at the pole (another box, literally on a pole) or merely moved the wire pair from the one service point ..to the other.

Now the junction points are fitted with a simple disconnect so that the technician can unplug all phones and isolate the outside service. He can then simply see if the problem is their's or yours. Before, when it was all AT&T (etc...etc.) they then needed to test each wire pair to determine which extension was the troubled one.
 
That picture shows a fuse block. Haven't seen one of them in years. Not sure what the POTS use to protect from voltage spikes these days.

If the wiring is connected correctly, There will be 2 twisted pairs in each line coming into the house. Normally, red/green is line one, and yellow/black is line 2.

Hope that helps a little.
 
WARING WARNING WARNING!!!

BE CAREFUL, RING VOLTAGE IS AROUND 90 VOLTS AC AND POSSIBLY CAN KILL YOU! 48 VDC (line voltage) ain't pleasant if you get between it and ground and it probably can kill too in "perfect storm" circumstances. Any doubts, call a pro!!!


I like to get an old telephone and cut off one end of the cord that goes into the jack. Strip it, and you'll see either green/red or green/red/black/yellow. Use the red/green pair to probe for dial tone on phone block/connectors/whatever. Dial a cell-phone with it so you know what line you're on.

The old phone green/red/cell phone trick is how I troubleshoot our 30 year old phone punch-down block phone system of great shame at work - rather than putting in a work order that takes weeks. If the fax line ain't working, it's a BFP (big freaking panic) and it needs fixed NOW not in a week! But then again, I'm a maverick and I hate spending your and my tax dollars on inefficient phone people when I can fix/run a new extension/whatever in 30 mins or less! I loathe waste!

later,
b
 
Agree with the red/green note above.

Note that when they disconnect service, you can still sometimes get a dial tone, but you can only call 911 or the phone company's various hook-me-up lines.

This will interfere with using a voltmeter.

I've taken 120v and it hurts until the next day. 90v of ringy tingly may be a suprise but you'll probably live through it.
 
My parents' service is hooked up. Theyre just trying to get it set up right, and since stuff was connected, disconected, reconnected, etc. it is a bit confusing.

The hope is that since only one of four wires should be active, that we can see constant 50VDC with a multimeter there???

Thanks again,

JMH
 
Originally Posted By: eljefino
I've taken 120v and it hurts until the next day. 90v of ringy tingly may be a suprise but you'll probably live through it.

LOL, one day I was stripping a phone line...with my teeth...when it rang. Surprise!
shocked2.gif
Thank god there's hardly any current in phone lines.
 
If I understand you correctly, you have one live pair coming to the demarcation point, with two pairs tied to it going into the house. Your question is - how do the two pairs entering the house correspond to the phones inside(?).

My solution would be to disconnect one pair of wires at the demark and see which phones go dead.

Pardon me if I have oversimplified your situation.
 
Originally Posted By: JHZR2

The hope is that since only one of four wires should be active, that we can see constant 50VDC with a multimeter there???


Yes, you will. However, sometimes "disconnected" lines aren't really and will still have voltage but no dialtone.

For that reason, better than using a multimeter for testing is to take a cheap telephone and a telephone jack, and connect alligator clip leads to the red/green wires on the telephone jack. Plug the cheap telephone into it and you've just made a test set, handy for checking wires for dialtone.

Incidentally, that protector you took a picture of is at least 50 years old and should not be the only protection on the line. There should be a telephone network interface near where the line comes off the pole and attaches to the house. This has the test jack and the circuit protector inside of it. This is also the "demarc" point. These devices usually say "TELEPHONE NETWORK INTERFACE" right on them. The test jack is for you to plug a telephone in to determine where the problem is, since the telco is no longer responsible for inside wiring. If the test jack does not work then it's an outside wiring problem that the telco is obligated to fix for free. If the test jack does work then you have an inside wiring problem, which is your responsibility to fix.

If you do not have one of these I'd suggest getting the phone company to install one (they should do it for free), as they have been required for about 24 years now.
 
There are two lines of demarcation. One is the termination block. That marks what is telephone company property and what is yours. This is common in terms of most things "attached to the house". This includes electricity and cable (etc.). This is on the exterior line. It's the "taps" that connect your power cable to the house (two knuckles). You own all attached to your house. For example, if you're paying for extra cable hook ups, that's a service agreement to maintain the lines. The cable company has no rights to them as being their property. The meter pan would be a like device to the phone service disconnect/isolator.

One forms a line of ownership division. The other "service" division.
 
Originally Posted By: Oldmoparguy1
That picture shows a fuse block. Haven't seen one of them in years. Not sure what the POTS use to protect from voltage spikes these days.


LOL, thats just a picture of a recent one that I found on the internet. I have no claim to the pic (should have cited a copyright, sorry).

The ones in my parents' house are MUCH older. Lots of white porcelain, old old wires, etc. Next time Im there Ill snap a pic of those :)

JMH
 
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Heh, heh. When I was a kid, we had crank phones. Big metal fuse box fastened to the soffit. Had 2 wooden fuses about 6" long in it. A tree at the NE corner of the lot got hit by lightening which jumped to the phone line. Blew the box and fuses to bits. Vaporized all the phone wires in the house. I was in the bathroom washing up. A jolt jumped from the plumbing the metal trim on the vanity, then to my belt buckle. Nearly knocked me out. I had burning nerves and sore muscles in my legs for a week.
 
Originally Posted By: Oldmoparguy1
Heh, heh. When I was a kid, we had crank phones.


lol - I can only dream of telling my kids... "Yeah son, when I was a kid, my first phone was Vonage - a VOIP service."
 
"Yes, young one, at one time we used fiber optics to transmit data. My ..my..how things have changed..."


LOL.gif
 
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