Any difference in quality between a 10m & a 20m RJ11 to RJ11 cable?

zoe

Would there be any difference in the quality of broadband if using either

a) a 10m RJ11 to RJ11 cable, or,
b) a 20m RJ11 to RJ11 cable

Assuming both cables are made by the same manufacturer. The only difference being the length.

Thanks

Soundman

Can't say exactly what the difference would be but, yes there will be a difference in quality. The longer the cable run is needed the more a signal will begin to degrade.

AlmightyCushion

Soundman wrote:

Can't say exactly what the difference would be but, yes there will be a difference in quality. The longer the cable run is needed the more a signal will begin to degrade.

I doubt it would be by any noticeable amout though.

leeroybrown

It shouldn't make any difference whatsoever so long as the signal quality (Attenuation and SNR) you are getting to the wall port is reasonable.

Inspector Gadget

This is a bit of a "how long is a piece of string" question... are both cables the same category? Are they the same type?

Assuming they're the same type (the most common being unshielded twisted pair), and the same category (most common being category 5), then distances of 10-20 metres are trivial - assuming (again, going with common) that you're doing 100Mbps or 1000Mbps then you're allowed up to 100 metres before you have to insert a repeater - I'm a little rusty on this, it might be 205 metres.

Typical broadband services in this country max out at about 8Mbps - way below what each type of service is capable of carrying point-to-point. This being the case, there won't be a blind bit of difference, apart from an immeasurably slightly longer ping time

Hope this helps,
Gadget

[edit: forget this, go with what my learned friend said immediately above ]

Soundman

Just been checking and the signal degradation is only noticable after a run of approximately 200feet. So you will be fine with either cable. Apologies for the last post I was basing it on the same way that audio would degrade the longer the run.

blorg

It will not make any difference at all. 10m extra in your house is nothing compared to the kilometers of wiring between you and the exchange.

EDIT: Note the OP is referring to RJ11, not RJ45 - e.g. he's talking about DSL over a telephone cable, not ethernet, the distances are in thousands of metres, not 100m like ethernet.

Inspector Gadget

blorg wrote:

EDIT: Note the OP is referring to RJ11, not RJ45 - e.g. he's talking about DSL over a telephone cable, not ethernet, the distances are in thousands of metres, not 100m like ethernet.

Woops :eek:

Sorry... concentration not at peak levels today...
Gadget

kaizersoze

I have my DSL modem plugged in using a 20m cable temporarily. The stats on the modem and connection speed are identical to when it was plugged in using a 2m cable.

zoe

Looks like there probably won't be any difference.

Thanks very much for the info guys, much appreciated..!

zoe

blorg wrote:

EDIT: Note the OP is referring to RJ11, not RJ45 - e.g. he's talking about DSL over a telephone cable, not ethernet, the distances are in thousands of metres, not 100m like ethernet.

Yes, it's an RJ11. DSL over a telephone cable, not ethernet.

Someone was telling me that if using a 20m cable then it should be constructed from twisted pair cable and not from flat cord.

Is this correct?

Also, I have seen an RJ11 to RJ11 cable for sale and it is like a ribbon. It has four individual cables that run parallel on a flat strip like a ribbon.

Would this a 'flat cord' cable, not a 'twisted pair' cable?

Inspector Gadget

Yep, twisted pair is exactly what you think it is, two wires wrapped around each other like someone's plaited it. For what it's worth, all of the stuff I've ever seen that was sold as "home phone cable" (so to speak) has been flat multistrand four-core stuff. Twisted pair is highly effective as a cheaper alternative to braided or foil shielding, but I've never seen it any of these used for phone-related stuff - twisting in particular makes the cable bulky compared to flat alternatives, and shielding drives up the cost.

Then again, I guess DSL is stretching phone technology further than anyone originally intended, but at the same time DSL equipment does have very fancy line measuring and analysis systems (I seem to remember that at least some of these were neural-net based back in the day?) that basically learn what kind of noise there is on the line and work around it as best they can; bear in mind, this is accounting for the noise all the way to the DSLAM (the other end of the cable in the exchange), not just the few metres of it inside your house. It shouldn't make a blind bit of difference how long the cable is in your house (unless, perhaps your line is just on the fringe of being suitable for use with whatever DSL technology your provider uses, typically several miles, don't have the figures to hand)

Hope this helps,
Gadget.

zoe

Thanks Inspector Gadget!

Sorry, but some of that is a bit over my head...:D

Someone was telling me that if I was getting a 20m cable then I should get a 'twisted pair' cable and not the 'flat four strand ribbon' type cable?

As according to them the twisted pair cable would be more effective over 20m than the flat ribbon.

Would this be correct?

Or would there be not really be much difference for a 20m cable?

Capt'n Midnight

Twisted pair means that interference recieved one one "side" of the cable is cancelled out by equal and opposite interference on the other "side". Even old cat 5 cable is rated to 100 MHz

with flat cable there is no cancelling - longer lengths are guaranteed to be noiser. Since it's designed for voice, you can use it in a low electrical noise enviroment up to about 0.003 MHz

Best to use twisted pair and put RJ 11 ends on it - or get some RJ45 couplers www.radionics.ie and use them to link the RJ11 to RJ45

zoe

Thanks, I know what you mean about the flat cable 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?

Snowbat

The Lloytron cable appears to be regular 4 core flat telephone cable. As they don't give any indication of *why* it might be better than regular cable, you can assume that "Broadband" and the pretty blue insulation are there only for marketing purposes to make clueless people believe it might be somehow better for ADSL use. Therein lies the point: 4 core flat telephone cable is normally used for internal residential phone wiring because it is perfectly suitable for the task, even for ADSL signals. The anti-crosstalk and EMF rejection properties of twisted pair are only beneficial if you're bundling multiple pairs, or a substantial part of the run will be in close proximity to other cabling. or in an electrically noisy environment. Even then, you'll probably not see any difference on a 20m run.

However, you might consider running a CAT5e cable - it is inexpensive, good quality, fine for POTS/ADSL, and gives you upgrade potential (4 lines, or 2 lines plus 100Mbit ethernet).

blorg

zoe wrote:

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

Well sort of but it won't necessarily be obvious as to what's inside a cable, you'll likely only find out by cutting it and investigating.

zoe wrote:

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?

No, that is absolute marketing bullshíte, it will provide no benefit whatsoever, any normal telephone cable should be fine.

If you just want a cable to string across your floor, whatever is fine. If you are installing something in a wall or something, where the hassle/cost of the installation is the point, cat5+ will give you some future upgrade potential; you could run a network over it for example. But sounds like you are just stringing across a floor, the 2.99 cable will be fine.

Note that CAT5 ethernet cable is twisted pair but is actually UNshielded, that is what UTP stands for (unshielded twisted pair.) Token ring needed shielded cable.