The importance of internal wiring!

Solair

Just a little example of how important internal wiring can be.

My folks have BT Broadband and upgraded to the max speed in their area, 7.6ish mbit/s. However, they were only getting about 3 to 4 mbit/s.

Their house's telephone wiring comes in through the attic and feeds 5 extensions in a star configuration i.e. all from one central point. There had also been some messing around on the line by eircom phonewatch, which had subsequently been changed over to GSM monitoring (no longer uses the phone line). So, lots of splices and various eras of wiring dating back to the 1970s.

The line had worked fine for slower DSL and also was quite OK for voice, fax etc.

I rewired the line, using an eircom DSL filter NTU and good quality CAT5.

Phone line comes into the attic on eircom good quality twisted pair, into a junction box (bought at Maplin), onto the blue pair on the CAT5, down to the eircom filter NTU socket. From the extension terminals on the face plate (filtered), the line goes back up to the attic on the orange pair in the CAT5 cable. It's joined onto another run of CAT5 that takes it to a junction box where the extensions connect in.

I rewired the extensions with CAT5 too, quite easy just pulled new cable to them and tidied up the wiring in the sockets.

Result : broadband is connecting at max possible speed, and achieving over 7mbit/s.

and the phones sound much sharper too!

If you've got somewhat dodgy DSL connections, it's absolutely worth doing!

Davy

I would agree with this, and the higher the speed the more the problem stands out. I noticed a big difference changing the speed profile around, the slow the more stable it is.

p2kone

could you do a speed test on the net and post the results?


regards
paul

Solair

I'll run a test later and post it up.

The biggest problem seems to be that the internal wiring used in a lot of houses is not twisted. Basic telephone wire, including that clipped to walls by Telecom/Eircom back in the day is just straight copper wire.

It's twisted in the network wiring (on the eircom side) to prevent crosstalk between circuits. Similar to CAT5. It carries data quite nicely (usually!)

However, in houses it made no difference as you usually only have one or two lines and the runs are very short (meters, not kms). So in most of the world they used straight wire without twisting the pairs.

If you've got very long runs of this, it behaves like an antenna and picks up RF noise that interferes with DSL signals.

If it's a DIY job, you can have inappropriate wire used, particularly in older installations as proper telephone grade wire was tricky to buy in the 1970s / 80s so it's often speaker wire or even door bell wire! The resistance profile of this is all wrong for data.

Basically, older phone line installations were never designed with data transmission in mind.

Solair

Sync Speed:

DownStream Connection Speed

7616 kbps

UpStream Connection Speed

672 kbps

BostonB

If I want to test my line is ok, and I want to elminate the internal wiring from the test. Can I just wire up a phone in the box in the wall outside? Then get it tested?

joe123

This sound exactly like what I need to be done. Ive 3mb broadband and am only getting download speeds of around 120kb.

It says on the router page max allowed 160/256

Ive no idea what you were on about in your post OP but who would do that sort of thing? Would eircom fellas come out and how much would the cost be?

Solair

BostonB wrote: »

If I want to test my line is ok, and I want to elminate the internal wiring from the test. Can I just wire up a phone in the box in the wall outside? Then get it tested?

You shouldn't wire anything to a box located outside as it's likely to be eircom property and could actually contain connections to other telephone lines.

You need to find the point where the line actually enters your house, it will terminate either on a little junction box, or an eircom/telecom eireann/P&T branded RJ11 socket.

You'll basically just have to find the wiring entering your home. It's easy enough if it comes in overhead, as you'll see exactly where it enters. But, if it's coming in underground, it will usually be fairly obvious too e.g. it'll be terminating on a junction or eircom socket in the hall.

You've a few options.

1) Re-wiring
or
2) Disconnect all of your internal extension wiring and just work with a single phone socket. Many people are happy enough to have DECT cordless phones and put the router where the first phone socket is.

The main thing to remember is to use good quality CAT5 and try to put the DSL router as the first thing on the line, and filter everything else. It's preferable to use a single splitter (as described above) as it means that you don't have DSL signals on any of the other wiring in your home and this can reduce signal problems.

You can buy central splitters online, they don't necessarily have to be an eircom NTU socket. Do a bit of a route around on google and even ebay. You can find some very suitable US hardwired splitters that will work very well on Irish lines. You can simply install one in your attic or hallway etc wiring a seperate telephone socket for your DSL router and then connecting your extension wiring into the filtered side.

E.g. http://www.homephonewiring.com/splitters.html all that stuff will work happily on an eircom line and can be used either plugged in with phone plugs or hardwired.

T (tip) = L1
R (ring) = L2

BostonB

I actually meant outside were it enters my house. The junction box in the wall of the house. I don't have Eircom BB as my line fails even though its a recent enough house. I'd like to check if the problem is inside the house or outside. Obviously eircom won't find and fix the fault.

Solair

If it comes in via an outside box flush in the wall, a little white box, then it's a very modern installation.

Your first phone socket which should be on the wall on the opposite side from that box is your "NTU" (Network termination unit)

Remove the face plate (2 screws) and you should find a second socket behind it if it's a very new socket.

Your internal wiring is connected to that plate. You can disconnect it from two screws on the back.

This document describes modern eircom wiring (post 2001) : http://www.reci.ie/Portals/0/RECIDocuments/technicalinfo/eircominterface.pdf

If your line's failing and the wiring's quite modern and new, it's possible that it's just incapable of supporting ADSL.

e.g. if you're more than 4km from the exchange it can get tricky.

Check the line quality itself by plugging in a phone, press any key to silence the dial tone and listen. If you hear buzzing or crackles you may have a wiring issue. If it's silent, it's possible the line is fine but just too long to cope with DSL.

BostonB

No crackles I've heard. I don't think its too long, but theres no way to say for sure. They said they could give me 512kb only.

http://picasaweb.google.com/TempestSabre/UntitledAlbum#5288877320670779394

Solair

Do you have 2 lines? You're wired up as if you do!

Alun

Solair wrote: »

E.g. http://www.homephonewiring.com/splitters.html all that stuff will work happily on an eircom line and can be used either plugged in with phone plugs or hardwired.

I've seen these before, but the ordering process seemed unnecessarily complex for International customers. Is there anywhere you can get these or something similar from a European supplier at all? It seems such a basic thing to be able to buy after all.

I'd have thought it was mainly poor/worn contacts in the various junction boxes.

Although you are right older installations don't use internal twisted pair which also is a factor. That and running them close to lecy cable!

BostonB

Solair wrote: »

Do you have 2 lines? You're wired up as if you do!

No one line, to three sockets. I have no idea whats going on in that photo.

Solair

Alun wrote: »

I've seen these before, but the ordering process seemed unnecessarily complex for International customers. Is there anywhere you can get these or something similar from a European supplier at all? It seems such a basic thing to be able to buy after all.

Unfortunately, there's no single European standard for analogue telephone service wiring. ISDN is totally standardised, but analogue phone service wiring comes in at least 27 national variations!

Phone companies developed these things in isolation from each other and just invented their own systems. In the past people couldn't buy telephones and install them themselves in most countries, they had to be either rented or bought directly from the phone company, or even in the most liberal telephone markets, they had to be meet weird national standards approvals.

The result has been that most European countries have their own weird ways of connecting up telephones. So, for the most part the equipment that works in one country doesn't necessarily work all that well in another country.

Ireland adopted "Western Electric" (AT&T/Bell Canada) standards for wiring in the 1970s as they were pretty much 'off the shelf'. At that time, BT was still hardwiring phones to the wall and had no standardised telephone sockets, so we couldn't adopt a UK standard either and P&T/Telecom Eireann saw it as sensible to adopt an already established and tried and tested system rather than coming up with something that might turn out to be problematic in the long term.

As it turns out the "Western Electric Modular Jack" system has become the de facto global standard and is used in an increasing number of countries around the world e.g. Spain, Australia, etc it also forms the basis for ethernet connectors and EuroISDN connectors.

You could buy UK splitter sockets, but they will have the wrong type of plugs and are setup to do 3rd wire ringing by default, where as in Ireland that's an optional extra.

Other EU countries systems are even less familiar!

So, a US or Canadian supplier tends to provide the most compatible stuff!

BostonB

I didn't realise you can put a RJ11 in a RJ45/8P8C socket. If the socket is wired correctly.

watty

And an RJ 11 6p6c too.

That's why the middle two pins are not used by networking.

Solair

It's actually a very well designed system, totally modular!

The BT system was basically a simple rip off of RJ11, by turning it sideways and making the plugs bigger! I assume they either wouldn't pay a license fee to use it, or wanted to ensure that people couldn't plug in their own phones unless BT provided them (more likely). The BT system lacks the structure and full range of connections though.

BostonB

Pity they didn't wire houses with that instead

Solair

BT actually uses RJ11 for ADSL connections btw, as do most other countries. Filters normally have the national standard, whatever that happens to be on one side and an RJ11 or RJ45 (which accepts RJ11) jack on the other side.

Eircom's faceplate filter actually has a fully wired 6 pin RJ11 on the right and an 8-way RJ45 on the DSL side. They both happily accept RJ11.

I'm not sure why they've RJ45 on the DSL side...

Although, I have heard rumoured that ETSI, the body that sets standards for European communication networks is proposing RJ45 sockets as standard for everything. I know they've recently started using them in France for new France Telecom installations in place of the old French phone plug which is an enormous contraption.


Take a look at this and you'll see what I mean about other European systems being even more complex than ours. This is the French system :

http://telephoniste.free.fr/circuits/priseT/

Note they have the phone plug beside a bulky 16amp French mains electricity plug, just to give you an idea of how huge it is!