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Thanks -- Some light bedtime reading material for later!

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 ).

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: 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.

Ray,
Only in Auckland Eh?.
20kb wouild be a dream here.

[This message has been edited by Trumpy (edited 02-12-2006).]

I can usually connect at around 44 to 45 kbps.

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).]

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).


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


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.


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!

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).]

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.


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.


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.

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.