Cable for ADSL

[jim_in_sussex]

Many thanks for the response to my recent post 'ADSL microfilters'.

From that it appears the best way ahead is to fit a BT master NTE5

linebox/ADSL adapter next to the incoming BT box at the front door (which is an old style box with a single plug in phone socket dating from the days just after BT stopped hard wiring everything & you could buy your own phone c 1986??). The existing daisychain phone wiring can plug into that for the filtered speech network. Whilst CAT5 cable for the unfiltered ADSL line needs to be run to the back of the house to the wireless router.

Q1 Why does CAT5 (twisted pair SFIUI) have to be used for the direct run from the front door to the router at the back of the house?

What is puzzling me is that the router is working OK in a temporary position off the daisychain (conventional, non-twisted pair, 4 wire tel cable) wiring at the end of a long run all round the house.

Q2 What type of CAT5 should be used? Screwfix list 3 types - basic; metal foil screened; smoke/fire rated. Definitely don't need the last, but which of the first two?

Q3 How easy is it to fit the connector ends onto CAT5 cable reliably? One dealer has tried to scare me into having him do it by saying it has to run at 100Mbps & you can't be sure 'without doing it properly' (meaning, I think, he would test with hf test gear). Should I be scared off? If no, what tools are needed to make the joint?

TIA

[David Hearn]

Assuming your wireless router is also an ADSL modem (ie. it plugs into the phone line) then standard telephone cabling can be used between the phone sockets and the router/modem. CAT5 only *needs* to be used for the ethernet output part of the router (ie. between the router and the PC).

As for making up CAT5 cables - you just need a crimp tool and a wiring guide (and some patience as getting all 8 wires into the correct slot can be a pain on some plugs). If the cable or the plug, or the joints are't up to spec, then you may have trouble using it at higher speeds - but I've never had a problem, and never had to test them other than a visual check to see if each wire is in the correct place, and by plugging it into a PC + hub/router and seeing if it works. No HF test gear etc.

Unless you're using metal plugs (not that common in home setups I think), just go with basic CAT5 cable.

Hope that helps

D

[Dave Liquorice]

Or simply get the required NTE with ADSL faceplate and replace that old BT box. Not strictly legal BWTH...

It doesn't, CW1308 is fine. You'd only run CAT5 if you placed the ADSL modem/router/WHY next to the NTE as you'd then be extending the ethernet wiring not phone wiring. A few extra feet of ordinary phone cable dedicated to the ADSL side isn't going to mess up the signal. It has, after all, survived several miles or so on similar cable from the exchange. What does mess it up is cheapo filters and odd length wiring stubs and/or doubtfull connections within the extension wiring.

Not applicable.

You need a proper crimper tool really. It's pretty hard to press the contacts into the wires without damaging them or the shell. The cable clamp also needs a fair bit of force to latch, which makes it tricky to do without damage. But as you don't need to use CAT5 for the phone wiring...

[Andy Mckenzie]

Q1 - You probably don't need CAT5 to the router from the splitter, twisted pair telephone wiring would do, I think, but in any case, rather than fit one filter at the master socket, why not have a filter at each phone. Bought from somewhere like ebuyer.com filters are cheap (£1 to £6) . That way you don't need to run an ethernet cable to anyplace that already has a phone socket.

Q2 - for most practical purposes cheap cable will do the job, given that in most domestic settings you aren't going to be pushing the cable to its performance limits. I bought one of the Screwfix £25 network starter kits that comes with cheap cable, and have had no problem with 100 Mbps traffic.

Q3 - Connecting CAT5 cable to 'Keystone Jacks', ie to female sockets is dead easy, with the right tool, and the tools are cheap (£1.79). Connecting the cables to male plugs is also easy, but the tool to do it is more expensive (£11 or so). I reckon that making up fixed runs as female-female and using pre-made patch leads to wire in the kit at the ends will keep things simple and neat. As I say I had no problem getting 100Mbps out of fixed wiring between various rooms in a domestic setting. If all you are doing is wiring up ADSL to a single PC, then you don't actually need 100 Mbps, as ADSL isn't going to (ever?) give you more than 8 Mbps, but anyway you sholdn't have a problem. Leave 'spare' cable tucked away somewhere along the run, so that if it doesn't work you can always chop an inch off and try again!

Andy McKenzie

[Set Square]

Unless it's very old, ordinary phone cable will use twisted pairs - but with less twists per unit length than CAT5. As ADSL speeds increase, it is more and more important to have the best possible signal to noise ratio (SNR) and twisted pair cable helps to achieve this - since any induced noise affects both conductors equally, and is self-cancelling. Having said, that *decent* phone cable is all you need.

As above, use decent phone cabble.

Don't fit plugs onto the end of your extension cable. Use a modified ADSL faceplate from Clarity which allows the digital extension wiring to be kroned** into the back. Use an RJ11 socket at the computer end, and again krone the wiring into it. Your router/modem cable will plug straight into this socket.

The Clarity site

contains a lot of useful information about NTE5's - as well as selling you the bits you need.

** Kroning refers to the use of Insulation Displacement Connectors (IDC) - which use a v-shaped slot in a metal connector, and the wire is forced into it using a special tool - piercing the insulation and making an electrical connection. You can get useless plastic tools for a quid or less - but a decent metal one which will last you a lifetime is only about a tenner from the likes of Screwfix.

[Mike Clarke]

Ordinary phone cable should be just fine on the "phone" side of the modem/router. But depending on how much wiring you are doing it may be more cost effective to buy just 1 reel of CAT5 instead of 2 separate reels since CAT5 can also be used for phone wiring. If it's a long run to the modem then CAT5 will have the advantage of being less susceptible to interference.

Just the plain basic stuff.

IDC telephone and RJ11/RJ45 plugs are meant to be used with flexible stranded fly leads, you could have problems fitting them to solid cored CAT5 cable. The best approach is to terminate the extension wiring with a suitable socket then use flexible fly leads to connect the appliances. Pre assembled fly leads are quite cheap and hardly worth the cost of the crimping tool and the hassle of making your own.

Wiring up the sockets is quite simple providing you use an insertion tool, if you intend doing much phone or network wiring then it's well worth shelling out for a "proper" insertion tool (about £7.50 from Screwfix) instead of using the cheap plastic ones.

The important thing to watch with terminating CAT5 network cable is to maintain the twist right up to the terminals, don't have more than 1/2 inch untwisted.

[Dave Liquorice]

The sheds are selling 'em now for less than the postage on a small order more.