Kitz Forum
Broadband Related => Broadband Hardware => Topic started by: hake on December 03, 2009, 05:57:50 PM
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I have 15 metres of Cat.5E 24AWG 2pair solid cable which I intend to run from the filtered faceplate to the router.
I imagine that this is better quality than the stuff that BT has run underground for a mile and a quarter from the exchange to my house so am I overoptimistic to expect very little difference in attenuation and errors compared with connecting the router to the filtered faceplate via a 1 metre cable?
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Edit. Ignore earlier version of this post. 8)
I would expect no discernible difference.
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Thanks HPsauce. No discernable difference will be just fine.
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I am at last in a position to commission my Cat5e 2pair ADSL cable. I need to know if a conductor in a twisted pair is electrically connected to the other? The answer is probably a no brainer to the cogniscenti which I am not a member of.
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No, each twisted pair is simply two insulated wires twisted together. There is no electrical connection between them.
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Thanks roseway. Sorry to be an ignoramus. Do you mean that one of each pair of wires carries a signal and the other member of each pair is simply there for noise cancelling? If that is so, I only have to connect one of each pair to the terminations at each end, presumably always making sure that the same signal carrying member of each pair is connected at each end.
Do you believe that I understand the matter correctly?
:-\
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Hi Hake,
A telephone circuit is a loop of a wire pair from the exchange, sometimes via a PCP Green Cabinet (Primary Connection Point), to your house.
That circuit MUST be kept as a twisted pair so that (in a rather a crude description) any noise induced in one half of the twist is then cancelled in the second half of the twist.
Where BT have managed to cross pairs within their cables the result is a very poor ADSL connection even if the voice frequencies are reasonable.
Don't expect miracles by the substitution of 15 metres of Cat 5E unscreened cable on a line length of probably a few kilometers.
I suggest you might be far better off getting a screened ADSL modem cable with RJ11 connectors on it such as those described here.
http://www.adslnation.com/phpapps/catalog/index.php?cPath=21&osCsid=cm05v71djvucdekopfp4gp8d94
There are plenty of other suppliers as well.
Kind regards,
Walter
Edit - @ Eric, Thanks for the most eloquent description below.
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Just to add to what Walter said, the twisted pair is what's called a balanced connection. That's to say, each wire carries the same signal, but they are in opposite phase (when one goes positive the other goes negative by the same amount). It's the voltage between the two wires which is the required signal. Because the wires are tightly twisted together, any interference is picked up equally in each wire, so it doesn't produce any voltage between the two wires to interfere with the signal.
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Postscript: After much grazed knuckles and lifted carpet, the Cat5e is in place. I found that the performance is best when the paired signal wires are connected together at one end only. The ADSLNation supplied cable is screened. There appears to be a speed difference of only 200kbps between the router being next to the NTE5 and on the other end of 15 metres of this cable, the slower value being when the router is connected thorough the cable.
Thanks for the advice and information.
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Now I'm confused. Why are you connecting the two paired wires together? You should choose one pair (normally the blue/white - white/blue pair) and connect one of the pair to the A terminal in the faceplate and the other to B, and at the other end (presumably an extension socket) one wire goes to terminal 2 and the other to terminal 5. You don't join the two wires together.
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It is only twisted to cancel noise, you just treat each wire separate as you normally would but try and keep the twist to as close as possible to the connection point.
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I tried the different permutations and this was the one that produced the best results.
I would like to see a diagram that shows how the terminations should be made up. I have looked long and hard and have yet to find one.
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It seems as if we need to clarify some descriptions.
Cat 5E is usually four twisted pairs, not just two. Perhaps Hake is using the ADSL Nation shielded 2 pair multi-stranded-flex cable normally supplied for RJ11 plugs?
If so, some care might be needed if this cable is being terminated in IDC type sockets as the effective wire diameter is likely to be different.
Kind regards,
Walter
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Is this (http://www.kitz.co.uk/adsl/socket.htm) what you are looking for Hake?
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I tried the different permutations and this was the one that produced the best results.
I would say the wire you are using it not very good and when you use twice the size (Two wires to one connection) you are improving the wire resistance.
Although if you connect the same twisted pair to one conection you are infact negating the twisted pair effect, or at least that is what I would have thought.
Is this (http://www.kitz.co.uk/adsl/socket.htm) what you are looking for Hake?
http://www.kitz.co.uk/adsl/socket.htm
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Thanks for the brain time and expertise you are all making available to me. I am using the ADSLNation Cat.5E shielded 24AWG 2pair solid cable.