# RJ11 to RJ11 Cable.  Any difference in quality?



## Becca (29 Jun 2007)

Are there any real differences in quality between various RJ11 to RJ11 cables of the same length?

As some on eBay are quite low in price, whereas some branded ones can be a lot dearer.

Also, if a 10m one is used instead of a 5m one will the quality of broadband received be of lower quality to using the longer RJ11 to RJ11 cable?


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## jhegarty (29 Jun 2007)

Like everything in life one will be of better quality than another....


but unless you live under a pylon, next door to a rte transmitter or run a data center it won't make a difference....


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## GeneralZod (29 Jun 2007)

Be more concerned that you've proper connections and nothing local interfering with the signal. Adding an extra 5m between yourself and the exchange will make no practical difference. That's probably less that 1% of your distance from the exchange.

Your DSL modem might have a function to look at the line characteristics.

You want to see low attenuation values (loss of power between exchange and your modem) and high noise margin (signal to noise ratio).

Expensive cables are a con as can be verified by looking at the line characteristics.


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## ryan-neil (29 Jun 2007)

It's a con, like paying 20euro for a usb cable, the cables have already meet the quality standards as defined by the cable itself.


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## olddog (29 Jun 2007)

If you plan to use a long cable then be sure that it is constructed from twisted pair cable and not from flat cord.


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## Carpenter (29 Jun 2007)

olddog said:


> If you plan to use a long cable then be sure that it is constructed from twisted pair cable and not from flat cord.


 
Why is this so important (I'm just interested)?


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## bacchus (29 Jun 2007)

See here


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## Becca (29 Jun 2007)

olddog said:


> If you plan to use a long cable then be sure that it is constructed from twisted pair cable and not from flat cord.


Does it usually state on the packaging of RJ11 to RJ11 cables either '_twisted pair_' or '_flat cord_'?

If not, is it possible to tell by looking at the cable which one of these it is?  

Is the '_flat cord_' cable literally flat?  Is it a 'ribbon' style of flat cable?

Also, do these '_twisted pair_' and '_flat cord_' options apply to RJ11 (not RJ45) as the cable is for DSL over a telephone cable, not ethernet.


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## Becca (1 Jul 2007)

olddog said:


> If you plan to use a long cable then be sure that it is constructed from twisted pair cable and not from flat cord.


I know what you mean about the flat cord now. I think it is that flat ribbon wire, the sort of wire that connects to a hard drive.

Is this type of RJ11 cable twisted pair cable?
http://www.batterymarket.co.uk/lloytron-10m-broadband-cable-rj11-to-rj11-p-271.html?currency=GBP

I suppose that should be an okay cable?

There's another similar cable made by Pro-tech that has *gold-plated* connectors which supposedly has "up to 10 times signal strength and speed" and has "double shielding and double blindage".  It's more expensive, but I suppose it won't make much difference to speed; would it?


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## Carpenter (2 Jul 2007)

bacchus said:


> See here


Very interesting, thanks for the link.


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## ang1170 (2 Jul 2007)

I wouldn't bother with twisted pairt for a domestic installation: it's main purpose is to reduce crosstalk (i.e. interference) between adjacent cables. This is a problem if you're running a few cables in a duct or whatever, but as it's almost certainly the only cable involed, it'll make no differece. The biggest problem with comestic cabling tends to be the number and type of connections involved rather than the cable itself.

By the way, high priced digital cables (e.g. USB, serial etc.) with gold connectors etc., are an absolute waste of cash. 

The only place I'd consider spending extra on cables are those carrying things like sound to speakers (you wouldn't believe the amount some high-end hi-fi audio cables can cost).


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## olddog (2 Jul 2007)

ang1170 said:


> I wouldn't bother with twisted pairt for a domestic installation......



Long flat cords will cause impedance discontinuities. Your ADSL modem is designed to cope with impedance discontinuities but if there are to many between you and the exchange the connection will sloow doown significantly or in marginal not work at all.


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## ang1170 (2 Jul 2007)

I won't respond to your direct point, as I'm not sure a technical argument would have much benefit to anyone, apart from scoring points of one another  

On thinking about it though, I'm sure that you'd agree that the best option for anyone is to put the broadband modem as close as possible to where the phone line comes into the house, and then use cat5 LAN cabling (or wireless) from that point on. This is preferable to stringing the analog phone line signal round the place (as we've both pointed out, the more connections and cables you have on this link the more problems are likely to be).

10/100 LAN cabling (i.e. not Gigabit), being digital, is much less prone to errors than analog lines.

BTW, in answer the the OP point about cable length: there's unlikely to be any difference between a 5m and 10m length of cable: it's already come (most likely) a few hundred metres to get to you. The key thing is that there's an extra cable (and connector) there at all.


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## olddog (2 Jul 2007)

Some of the stuff on here

[broken link removed]

( some other manufacturers offer similar products )

can be very handy for distributing data around a domestic house

.............Of course its a fair shift in the budget from an RJ11 - RJ11 cable


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## Becca (3 Jul 2007)

ang1170 said:


> the best option for anyone is to put the broadband modem as close as possible to where the phone line comes into the house


So if the telephone socket is in the downstairs hall and the pc is upstairs, should I place the modem in the hall beside the telephone socket and run the cabling from the modem upstairs to the pc?

Rather than placing the modem upstairs beside the pc and running different cabling from the telephone socket up to the modem?


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## ang1170 (3 Jul 2007)

I should have qualified what I meant by "best": in the post above I was using it in terms of "least likely to cause problems".

The cheapest way of doing this is to run phone cable (i.e. RJ11 at either end) from downstairs to upstairs. If it works, and it almost certainly will with no problems whatsoever, then that's the simplest thing to do.

However, if the line to the exchange is marginal, the signal degradation caused by the extra length of cable may cause it to fail, either completely, or to give a reduction in speed (the modem will fall back to whatever speed it can get). In that case, the best thing to do is as I suggest and put the modem directly onto the line as it comes into the house. In that case you'd have to run CAT5 cabling (which has RJ45 connectors) from the modem to the PC. CAT5 cable is more expensive than phone cable. 

The chances are however, that there will be absolutely no difference in terms of throughput which way you do this. as a first option therefore, I'd be inclined to go with putting the modem at the PC (and against my previous advice on what's "best"!).

Another alternative is to go (local) wireless, which gets round the problem of having to wire internally. In that case, place the modem as close to possible to where the phone line comes in. However, assuming your PC doesn't already have a wireless adapter, you'd have to buy one. It's also not as straightforward to set up (e.g. unless you want your neighbour's sharing your connection you have to set up password protected access).


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## Becca (3 Jul 2007)

Okay.  Thanks very much _ang1170_.  I'll try the RJ11 cabling first and see what happens.


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