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Posted By: Trumpy Most Common Telephone Service? - 10/06/05 07:20 AM
Guys,
We tend to concentrate on the Electrical side of Services to Resi and Commercial places.
I'd be interested to know what comes in as standard from your Telco or in places where you have worked?.
A wide open question I guess, but is it any les important, in these days of high-speed communications?.
Posted By: gfretwell Re: Most Common Telephone Service? - 10/06/05 02:08 PM
Telephone service at the customer end hasn't really changed much since the 20's. The media has improved but the basic POTS is regulated to the point that it can't change. Al Capone's candlestick phone will connect and dial on a DSL line.
The central office changed from several floors of clicking relays to a small box humming in the corner and the trunks are digital fiber but the last hundred feet from the concentrator to the house is still a copper pair with a 10-48v analog signal on it. The unbundling of "Ma Bell" and the rise of consumer owned equipment created the Demark box on the outside that has a RJ11 plug in it so you can isolate the "house" side from the Telco side for troubleshooting.
If a phone works in the Demark, it isn't the Telco's problem and they will charge you a stiff service call fee (~$135-150US)if they come out.
Posted By: mkoloj Re: Most Common Telephone Service? - 10/06/05 03:39 PM
Gfretwell is mostly right about the residential end of things with the except the newest thing is Voip service being available to the residential customer, something I have switched to just recently, I get my telephone service form my cable television provider. I cannot tell the difference between the circuits when I am using it. The only real concern I had is if the power goes out I would not have dial tone, so I put in a ups for the cable modem.

As far as business service goes it has come a long way away from the old clicking relays to high speed data circuits transmitting voice digitally like PRI which can be pumped into a phone system and give you 100 lines from 1 circuit.
Where I am we have a PBX (about 4000 phones and 3000 DID's) equipped with Voip and have IP phones at some remote sites that connect via the ethernet network (which is tied to our main site via T1's) this enables us to dial direct 4 digit extension's to sites that are miles away. We also have OPX circuit's that allow us to put extensions from our PBX at remote sites.

Other sites we have our own tie lines for voice and have remote shelf's full of cards(emulate cards at our main site) that are connected to our PBX and I can do programming on the phones from my desk and the phone is on the other side of town.

There are a multitude of different way's business's can configure and interconnect facilities to behave and give functions just like as if the people were sitting in another office at the same site but they are actually on opposite sides of the globe.
These types of services often pay for themselves when compared to paying long distance charges if there is a heavy call volume between the sites that need to communicate.

We have a MUX installed at our site that is fed with fiber from the street and breaks down our digital circuits to copper from the fiber. Gone is the old metal can with a rat's nest of cross connections except for a couple of random DSL lines and emergency POT's lines we have in case of emergency which we would be reduced down to a system of phones that are placed in strategic locations to enable calls to be made in the event that our switch is not functional.

If disaster strikes, which it hasn't yet (fingers crossed) we would flip 6 toggle switches and the phones which are normally fed with extensions from our PBX would have their feed transferred to one of the backup POT's lines. Basically a manual transfer switch for telephone service.

[This message has been edited by mkoloj (edited 10-06-2005).]
Posted By: classicsat Re: Most Common Telephone Service? - 10/06/05 08:57 PM
The service is the same, wiring and connection methids have changed.
In the (not too) old days the inside wiring was 3 or 4 wire "JKT", previously it was an open twisted set. It has evolved into 3 pair cat3, or 4 pair cat5.
The custoumer termiation inside evolved from hardwaired, 4 pin plug to RJ11.
Outside, we had a protector made by Reliance elcetric, which had fuses and carbon blocks.
The repaced it with a smaller plastic one when I got highspeed (they had no problem with the fact I had cat 3 wire). Where I am ( smaller independant phone company), they don't use "NIDs", at least that I've seen.
Posted By: brianl703 Re: Most Common Telephone Service? - 10/11/05 07:19 PM
Starting before 1974, Bell prewired new construction houses with 5 or 6 twisted pair cable that would likely meet the specs for a Cat2 or a Cat3 cable if tested.

With the breakup of Bell in the early 1980s, responsibility for prewiring of new construction houses fell to the electricians who mostly used the commonly-available 4-wire, non-twisted, "JKT" cable for telephone prewires.

According to information I've read, that 4-wire cable was designed and intended (by Bell) for useage on retro-fit installations where the wire would be exposed along a baseboard (the non-twisted construction and 4 wires resulted in a small diameter, smooth, perfectly round cable which looked acceptable against a baseboard). Anything that was a pre-wire install (where the cable is concealed in the wall) was to use 5 or 6 twisted pair cable.

Since about 2000, the FCC rules specify that Cat 3 cable is the minimum acceptable for telephone wiring (for new installations).


[This message has been edited by brianl703 (edited 10-11-2005).]
Posted By: gfretwell Re: Most Common Telephone Service? - 10/12/05 02:14 AM
If you are as old as me you remember Ma Bell invented JK. It used to be ~22ga 3 wire and it didn't really become 2 pair until the Princess phone (It's little, it's lovely and it lights) The yellow/black was the light, from the first wall wart.
Twisted pair started when multiple lines became an issue, usually in apartments.
Most single family phones still got wired with R/G/Y/B untwisted wire into the 80s. Computer modems and 2 line service brought the Cat 3 wire.
Posted By: pauluk Re: Most Common Telephone Service? - 10/12/05 04:58 PM
Domestic lines right up until the early 1980s here were often installed as a single-pair using a type of cable which looked very much like zipcord (except it was solid-core).

Multi-pair cable is now installed as the norm, but as far as the Telco goes, they run to a single master jack in the home, and that's as far as it goes. Anything beyond that is entirely up to the homeowner to arrange and install.
Posted By: gfretwell Re: Most Common Telephone Service? - 10/12/05 05:07 PM
The standard in the US is the telco stops at the Dmark on the wall outside. There is an RJ11 in that box that "the house" plugs into. If a phone works in the Dmark it isn't a telco problem, unless you pay the extra couple bucks a month for an "inside wiring" service contract. A service call caused by "inside wire" without that contract is well over $100US.
Posted By: pauluk Re: Most Common Telephone Service? - 10/13/05 01:33 PM
Modern installations here use the NTE5 unit (NTE = Network Termination Equipment) which acts as the demarc in a similar way:
http://www.austin-taylor.co.uk/pages/nte5.htm
Posted By: Trumpy Re: Most Common Telephone Service? - 10/30/05 10:06 PM
Paul,
Quote
Domestic lines right up until the early 1980s here were often installed as a single-pair using a type of cable which looked very much like zipcord (except it was solid-core).
Yes, that's what I have here in this house, to the Primary socket in my Lounge.

Quote
Multi-pair cable is now installed as the norm, but as far as the Telco goes, they run to a single master jack in the home, and that's as far as it goes.
These days Telecom will only run thier incoming line to a Demarcation box on the outside of the house, the rest is up to you to provide.

Here is a specification of the requirements for Residential installations in New Zealand.

{Message edited to add link}

[This message has been edited by Trumpy (edited 10-30-2005).]
Posted By: pauluk Re: Most Common Telephone Service? - 11/01/05 05:00 PM
Quote
Here is a specification of the requirements for Residential installations in New Zealand.

Thanks -- Some light bedtime reading material for later!
Posted By: pauluk Re: Most Common Telephone Service? - 11/04/05 10:34 AM
I just had a read through that document last night. It's interesting to note that NZ is now abandoning the BT 3-wire system for a simple 2-wire hookup.

Other minor variations I noticed from the British influenced wiring:

Jack terminals are numbered the opposite way round to here. I'm assuming NZ adopted the original BT plug numbering. There was much confusion over here due to a monumental screw-up in communications which led to the plugs and sockets being numbered the opposite way round to each other.

The use of red/blue/green/white fixed wiring in older systems. They were the colors used for the flexible cords on phones here, but the old 4-wire fixed cable was blue/orange/green/brown.

The drawing to show the wiring conversion (last page) looks like it was copied directly from the old GPO 746 schematics, but as the phones were the same I suppose that's not surprising (except for your backwards dial, of course [Linked Image] ).
Posted By: RODALCO Re: Most Common Telephone Service? - 01/12/06 10:54 AM
Here in NZ we use terminal 2 and 5 for the standard 2 wire system. To get a bell going a 1.8µF capacitor can be hard wired to terminal 3 in the jackpoint if not already provided.

The supply to my house is 2 core OH black twisted wire, which is also my snail pace internet connection while I write this.
It's ok for text but slow for photo's.

If anyone is interested: [Linked Image] I made an on line sensing circuit which drops all the phones off the phoneline to increase my modem speed to about 50.8 or 52 kB by means of a small 2 pole relay. Before it was 30 kB.
Also a hourmeter is provided to see how many hours I use my phone line. [Linked Image]
Posted By: Trumpy Re: Most Common Telephone Service? - 02/12/06 11:21 AM
Ray,
Quote
If anyone is interested: I made an on line sensing circuit which drops all the phones off the phoneline to increase my modem speed to about 50.8 or 52 kB by means of a small 2 pole relay. Before it was 30 kB.
Also a hourmeter is provided to see how many hours I use my phone line.
Only in Auckland Eh?. [Linked Image]
20kb wouild be a dream here.

[This message has been edited by Trumpy (edited 02-12-2006).]
Posted By: pauluk Re: Most Common Telephone Service? - 02/12/06 01:18 PM
I can usually connect at around 44 to 45 kbps.
Posted By: djk Re: Most Common Telephone Service? - 02/14/06 11:13 PM
In Ireland the most recent installations all terminate on an "NTU 2001" which basically is a demarkation point, much like what you're describing in the USA except that it is incorporated into a surface mounted telephone socket.

The telco installs a standard surface mount wall box, then a thin plate goes over that which has lugs on the back for terminating up to two telephone lines PSTN or ISDN.
There is an 8-way RJ12 socket on the front of this plate.

Another plate fits on top of this with a non-locking 8-way RJ12 on the back of it. There are a few different varieties of front plate available to the telco. 1) Standard RJ11 outlet with terminals on the back for connecting any extension wiring to.

2) ADSL splitter. This has all of the above, as well as an ADSL filter and has 2 sockets on the front 1 filtered, one raw for the DSL modem. All of the extension wiring's filtered by this plate.

The front plates also have jumpers that can be set to allow lines to be looped through alarm systems to allow the alarm to sieze the line etc.

There is also a 2-line plate available which has two RJ11 sockets on the front "Line 1" and "Line 2" .. (various jumpers inside let you configure the sockets to have 1 or both lines etc etc) any extension wiring is connected to terminals on the back of this plate.

You can also configure the front plate to operate with an ISDN connection. In this case, the ISDN line is wired to the back of the socket as normal, from there (via CAT5) it goes on to a "Plug & Play ISDN" NTU box installed near by. This has the RJ45 sockets for ISDN devices and also provides a pair of analogue PSTN ports. These are fed back through the same CAT 5 cable to the telephone socket again and are presented via the front plate. Any extension wiring in the house is once again wired into the back of the plate.

If the telco wants to prove that there is an wiring problem that is nothing to do with them, they can simply remove the front plate and plug in a test phone. If it works, the house wiring's faulty and that's entirely the customer's problem thesedays.

The "NTU 2001" provides surge protection against lightening etc etc as well as being the demarkation point.

----

In older installations the telephone line would terminate on a little grey junction box, typically in the hallway or in the attic. Any telephone sockets were wired in (2-wire) to this point. Each individual telco supplied socket contained a surge arrester & other circuitry. If any cheapo-extension socket was wired, it had to be daisy-chained off the output side of one of the telco provided sockets.

Again, the sockets had jumpers that allowed various configurations of the 8-way RJ11/12 socket for various functions.

That system lasted from the late 70s right through to the 90s.
---

Before the introduction of RJ11 in Ireland phones were either connected with phono-jack style connectors similar to those used on manual operator switch boards or, more frequently, hardwired.

Pretty rare to find such an installation still in use though as the telco in its monopoly days systematically installed RJ11 sockets as exchanges (switches) were converted to digital. Rotary dialling telephones were rapidly replaced with touchtone / DTMF equivilants.

Standard 1960s and 1970s issue phones here were Northern Telecom manufactured 500 type.

Nortel continued to supply the high-quality telco supplied phones right up until the 1990s. (you could buy whatever you liked, but if you bought it from the telco it would be nortel, alcatel or siemens.. they didn't stick their name on cheapo stuff!)

Nowadays the telco (eircom) still sells phones, but they're all DECT (digital european cordless telephony) siemens or sagem handsets rebadged with their own logo with eircom's network service codes etc preprogrammed into the menu system.

But, you could still whack an RJ11 plug onto Al Capone's candlestick phone and plug it into an Irish phone socket and the digital ericsson or alcatel switch would quite happily understand its pulse dialling and connect a call.

Not a lot has changed! .. it'd even work over the analogue interface of an ISDN line or a VoIP line.



[This message has been edited by djk (edited 02-14-2006).]
Posted By: pauluk Re: Most Common Telephone Service? - 02/15/06 01:18 PM
Quote
In Ireland the most recent installations all terminate on an "NTU 2001" which basically is a demarkation point, much like what you're describing in the USA except that it is incorporated into a surface mounted telephone socket.

The U.K. uses the "NTE5" for a similar purpose:
http://www.austin-taylor.co.uk/pages/nte5.htm

The pictures on that page don't show the unit with the lower panel removed, but that lower plate which contains the front jack and the IDC connections for extension wiring just plugs into the jack on the main section. The jacks are the BT431 type, not U.S. modular,
although the latter have now become the norm for the phoneend of cords (complete with a lot of confusion as to whether the line should be on the inner or outer pair).

Quote
ADSL splitter. This has all of the above, as well as an ADSL filter and has 2 sockets on the front 1 filtered, one raw for the DSL modem. All of the extension wiring's filtered by this plate.

Several manufacturers turn out ADSL filters for the U.K. market which are a direct slot-in replacement for the lower panel of the NTE5. For example:
http://www.adslnation.com/products/xtespec.php

Quote
Before the introduction of RJ11 in Ireland phones were either connected with phono-jack style connectors similar to those used on manual operator switch boards or, more frequently, hardwired.

Ditto here. The old Post Office 1/4-inch jacks came in 4, 5, and 6-way versions to allow for all the various extension plans and bell arrangements which were in use at the time (it was complicated by the fact that the GPO used to like wiring multiple bells in series, so the jack arrangements had break contacts to accomoodate that).

Hardwired was pretty much the norm for most domestic installations until the modern style connectors arrived in the early 1980s.

Quote
But, you could still whack an RJ11 plug onto Al Capone's candlestick phone and plug it into an Irish phone socket and the digital ericsson or alcatel switch would quite happily understand its pulse dialling and connect a call.

Same here. The System X and System Y (AXE10) exchanges which make up the network now will still happily accept pulse dialing. Just as well considering the Western Electric 500 phones I have connected! [Linked Image]
Posted By: djk Re: Most Common Telephone Service? - 02/16/06 01:21 AM
Paul,

The NTU 2001 type sockets here are VERY similar to the UK concept, just with more jumpers and RJ11 and RJ45 sockets.

Also, for DIY-friendilenss IDC connectors arn't used for the extension connection on the back of the plate. We just have a pair of screw down connectors for each line.

For some reason the DSL filter plate has an RJ11/45 combo socket on the DSL side and an RJ11 on the phone side.
Both will mate with RJ11.

The designation of the terminals here is :
L1 (tip)
L2 (ring)
R - obsolete ringer wire. never connected, but present in some sockets. It was to be used where a 3-wire hardwired phone was to be connected to the output side of a modular socket. We've never had modular 3-wire phones.
- you could, in theory, wire a UK-extension socket to that side of an old irish socket and it would work fine.. if you hooked up the ring wire to the R terminal.
That arrangement was probabally extremely rare as Telecom would have removed the old pulse-dial phones on installing the modular sockets.
For some reason called "JM1" "Jacks Modular 1"

eircom's sockets are all made by Siemens-Rutenbeck, but in Ireland not Germany.

--

Btw, 3-wire ringing wasn't by any means unique to the UK... there were similar arrangements in other European countries e.g. France in the days of pulse dial.


In Ireland the 3rd wire was never used UNLESS there was to be more than one phone. Normally, you'd find the phone hardwired with the tip lug on one terminal and the ring and 3rd wire ringing wire on the other lug.
If you'd multiple extensions then anti-tinkle wiring was done if necessary. It depended on the phone models etc etc. The Nortel 500 style phones didn't appear to tinkle anyway.

By the time DIY wiring was allowed, in the 1980s, most lines had modular sockets anyway.
(Pre 1980s the telco did ALL the wiring. You couldn't alter any of it)


[This message has been edited by djk (edited 02-15-2006).]
Posted By: pauluk Re: Most Common Telephone Service? - 02/17/06 03:27 PM
Quote
Also, for DIY-friendilenss IDC connectors arn't used for the extension connection on the back of the plate. We just have a pair of screw down connectors for each line.

That's a interesting point. Given that the whole intent of the NTE5 was to allow for DIY extension wiring without anyone having to get at the network side of the interface, it would have probably been more appropriate to provide screw terminals. The extension jacks are availble in both IDC and screw-terminal versions.

Many DIYers will just try to jam wires into IDC connectors with any convenient small screwdriver. I've had a lot of bad-connection reports which have turned out to be IDC connectors which have obviously been so abused.

Quote
The designation of the terminals here is :
L1 (tip)
L2 (ring)
R - obsolete ringer wire.

The BT jack coding is just numbers: 2, 3, 4, 5. Assignments for a standrad single line are:

#2 = Ring
#3 = Ringer wire
#4 = Spare
#5 = Tip

Jacks also have 1 and 6 for the outermost pair, but they are not used on normal domestic wiring and even if 3-pair cable is used, they are often left unconnected, the white-green pair just coiled up loose in the box.

As I've mentioned before though, thanks to a monumental screw-up in communications when the new BT connectors were being implemented in the early 1980s, the plug numbers run the opposite way to those on the jack (i.e. 1=6, 2=5, 3=4).

I've seen plenty of cheap jacks in which the manufacturer has erroneously used the plug numbering for the socket. You can dial out, answer calls, as normal of course as you just have tip/ring reversed, but because the ringer wire ends up on #4 instead of #3, there's no incoming ringing. That misnumbering causes a lot of confusion when people links the numbers and don't realize what's happened.

Quote
If you'd multiple extensions then anti-tinkle wiring was done if necessary. It depended on the phone models etc etc. The Nortel 500 style phones didn't appear to tinkle anyway.

Western Electric 500 (and 1500/2500) don;t need it either. The North American phones don't seem to suffer from the "dial tinkle" problem due to the different ringer design.

The old British GPO 300 and 700-type phones with unbiased ringers did though, so the 3rd wire was standard provision where extensions were involved. For party line service, they also included extra wiring to prevent the station Y phone from tapping when station X dialed, and vice versa.

On the 700-sets, a small thermistor was fitted in series with the bell. On earlier 300-type wiring, they would sometimes actually use a bridge-rectifier and slugged slow-to-operate relay to connect the bell to the line only when incming ringing was detected.
Posted By: RODALCO Re: Most Common Telephone Service? - 02/21/06 07:26 PM
I have to say that for sending photo's the modem speed drops down to 5 or 6 kB quite often.

Must be something that text goes through faster then digital photo data.
Posted By: Trumpy Re: Most Common Telephone Service? - 03/09/06 04:22 PM
Since TelecomNZ "announced" higher "broad-band" speeds of 2.5MBps those of us that aren't with XTRA are slowed down.
It takes me 3-5 minutes to load a single page these days.
Same price less service (2kbps, I was better off on dial-up).
The speed increase only includes those that are customers of TelecomNZ.
And if you are a child that has rich parents that don't mind the cost, go for it.
And you you also get a paltry 128kbps upload speed thrown in.
No XTRA charge for that though.

[This message has been edited by Trumpy (edited 03-11-2006).]
Posted By: Trumpy Re: Most Common Telephone Service? - 04/13/06 02:01 PM
Draft Document PTC 106 has been released for comment on Residential Telephone installations.
It looks not unlike the PTC 103 document I linked to above, but there are a few changes in this new document. [Linked Image]
Posted By: djk Re: Most Common Telephone Service? - 04/15/06 08:12 PM
I recently re-wired the phone installation in my apartment and found that my line's drastically improved in terms of quality. DSL was always ok, seems to comfortably carry my 3mbit/s ISP connection.

However, it was interesting to use a dial up modem as a benchmark for before and after.

Before the rewire: 45kbps
After : 52Kbps

The old wiring included some horrible DIY connections using normal flat non-solid telephone wire pushed into IDC connectors and wound around them.
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