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personthingy
16-07-2005, 09:35 PM
Righto...

Two observstions:

1. Cat 5 cable uses 4 twisted pairs.
2. The network cards seem to only use 4 wires, or 2 pairs.

Now i'd like to give my son a phone and a network connection in the sleepout down the back of my section, which will involve about 40 metres of cable running to pretty much the same distrobution points. Theres also a second sleepout further on that could be handy to have a phone in.

I figure that seeing they are all twisted pairs induction between pairs must by minamal, yet i see people allways running a seperate cable. There may be a good reason for this, or perhaps its just because thats the way it is done. Conversations with tradespeople tend to support the latter reason for this practice. :groan:

Is there any good reason why i cant use one or both of the unused pairs for the phone lines? If not why not.

Billy T
16-07-2005, 10:01 PM
Hi PT

For non critical applications you most certainly can use the other pairs. It would be pointless having the extra pairs if they couldnt be used at all.

The only issue might be transients on one pair corrupting data transfer on another, but that really isn't an issue for the average user.

Cheers

Billy 8-{)

somebody
16-07-2005, 10:04 PM
I think there are reasons which someone like Godfather or GrahamL will be able ot explain, I suppose if it works, then why not do it.

I can tell you that a friend of mine did precisely what you intend to do, when running network + phone line to a temproary office about 2 years ago. The cable was about 30m long, and there didn't seem to be any major problems.

personthingy
16-07-2005, 10:21 PM
Now one other question.....

Would it be fine to tack the cable under the horizontal bits of wood that hold the fence up?

It may get damp, not underwater, and not in direct sunlight.

When i sell up and move on i fully expect to sell a gutted shell to a bulldozer driver wanting to develope the land.. Therefore i am not interested in apearance, just that it works. :)

somebody
16-07-2005, 10:40 PM
You're not supposed to, but in saying that, I've seen a CAT5 cable hung between two buildings cable-tied to a length of conduit for about 10m, in wind and rain, and it worked fine (although a bit slower than it should have been).

Do you have some old garden hose which you could run the cable through? It might give you a bit more piece of mind. When you tack the cable to the underside of the fence railings, it could damage the insulation protecting the cable.

Billy T
16-07-2005, 11:02 PM
Would it be fine to tack the cable under the horizontal bits of wood that hold the fence up?


If it is not expected to survive for too many years, and you use oversized staples to support it (but not kink, crush or compress the outer sheath in any way) it will be fine.

Cheers

Billy 8-{)

personthingy
16-07-2005, 11:11 PM
Thanks Billy and Somebody

I thought id best ask before i went and did it.

:D

i've just popped over to CF1
might see you later on?

Chris.

beama
17-07-2005, 02:09 AM
yes you can use the unused pairs in cat5 for telephone, you need a cable spilter (at both ends) and a means to hook up to the telephone line. WE use the unused pairs on our network for this purpose. You can also use the unused pairs to connect up to 2 pcs to the same network connection using this technique but you need pair matching spilter on both ends of the cable ie wall socket and distrubtion cupboard.
We have not experanced any data or crc errors due to using this technique.

Prescott
17-07-2005, 02:14 AM
you could run the cable through some pipe, or alkethene (spelling), that might make it last longer

personthingy
17-07-2005, 02:36 AM
yes you can use the unused pairs in cat5 for telephone, you need a cable spilter (at both ends) and a means to hook up to the telephone line. WE use the unused pairs on our network for this purpose. You can also use the unused pairs to connect up to 2 pcs to the same network connection using this technique but you need pair matching spilter on both ends of the cable ie wall socket and distrubtion cupboard.
We have not experanced any data or crc errors due to using this technique.splitter? Ok the telephone line will be my PABX, and thats right by the place where the network switch will go. I assume i'll have to carefully sent the phone pairs out to the side while taking care that the computer network pairs are connected as per normal. In the sleepout that will mean having a phone jack right beside the computer jack. At the network switch that will mean having a pair go from the PABX to the same deal as the sleep out, and running a patch lead to the network switch..

Does that make sense or am i opening a can of worms for myself here?

personthingy
17-07-2005, 02:40 AM
you could run the cable through some pipe, or alkethene (spelling), that might make it last longer15mm(?) garden hose scraps is something i have a lot of. :)

personthingy
17-07-2005, 02:51 AM
You can also use the unused pairs to connect up to 2 pcs to the same network connection using this techniqueMy son has a 10Mb network hub for all his toys, which are mainly PCs rebuilt from junk found in skips. We dont need to run more than one "line" for the data, and given the ever decreasing cost of switches, i can see very little reason why people insist on running everything in a network individually back to one central point in a building. I'm just providing access to the net and filestorage for him, plus a phone extension.

Edward
17-07-2005, 03:50 AM
You're not supposed to, but in saying that, I've seen a CAT5 cable hung between two buildings cable-tied to a length of conduit for about 10m, in wind and rain, and it worked fine (although a bit slower than it should have been).

Do you have some old garden hose which you could run the cable through? It might give you a bit more piece of mind. When you tack the cable to the underside of the fence railings, it could damage the insulation protecting the cable.

I've managed to get a small 2pc network running on a 2 story by coiling the network cable round a drain pipe and through the windowframe :D

Prescott
17-07-2005, 06:58 AM
15mm(?) garden hose scraps is something i have a lot of. :)

that should do, as long as it fits of course :p and that there is no leaks in it.... but i would also keep that out of the direct sunlight too

pctek
17-07-2005, 10:18 AM
You can split it for what you want it for. But if you were to be using 100mb you'd need the whole 8 wires.

beama
17-07-2005, 12:19 PM
splitter? Ok the telephone line will be my PABX, and thats right by the place where the network switch will go. I assume i'll have to carefully sent the phone pairs out to the side while taking care that the computer network pairs are connected as per normal. In the sleepout that will mean having a phone jack right beside the computer jack. At the network switch that will mean having a pair go from the PABX to the same deal as the sleep out, and running a patch lead to the network switch..

Does that make sense or am i opening a can of worms for myself here?
if worms you want ill add some :D
you only need one connection , face plate, jackpoint (which ever name you wish to use) in each location. That where you use the cable spliter, they are colour coded solong as you match the colours when pluging in the phone and pc, your away
this is want tricky dicky has (http://www.dse.co.nz/cgi-bin/dse.storefront/42d9847c0deb2f682740c0a87f990775/Product/View/XH4248)

Billy T
17-07-2005, 01:25 PM
You can split it for what you want it for. But if you were to be using 100mb you'd need the whole 8 wires.

Where did you get that idea PT? I run 100Mbs on a single pair network.

I can't see why splitters are required either, you just make the cable longer than you need at the tail and bring the phone pair out to a separate phone outlet. Multiple phones can be connected in star or series-parallel configuration without any special connection systems.

Your network switch takes care of data distribution and that will be automatically be in star configuration, even if you use multiple pairs within the one cable. So long as you leave the individual pairs twisted, they can be left quite long outside the sheath at the termination point.

Keep it simple.

Cheers

Billy 8-{)

personthingy
17-07-2005, 02:37 PM
???? :confused:

OK, just when i thought this was starting to make sense, it gets o so confusing! :o

So lets assume i get a lenth of cat 5 cable cut to lenth with the plugs pre crimped in place. I drag it round the fence line beneath the rails through pipe, garden hose, all manner of things to protect it from the elements and feet. I then take each end and strip the insulation back say 200mm. I then snip back 2 of the pairs (3?) so i can use them for other things, such as the phone extension for the sleepout. I then attach the pairs i wish to divert to the connecter thingy on the PABX at the house end, and 2 a phone jack on the other. The ready crimped RJ45 plugs can go into the 10Mb hub in Ziggys room, and the as yet unbought 100Mb network switch in the house which talks to all the other toys in the house by a less doctored set of RJ45 cables.

Is this a workable concept?

If so.....
Which pairs must stay with the RJ45 prewired plug things?
Which pairs may i safely divert?

Thanks!

pctek
17-07-2005, 04:03 PM
Where did you get that idea PT? I run 100Mbs on a single pair network.


If you are using category 3 or 4 cables with 100M LANs ANYWHERE you MUST use the 100Base-T4 standard (it uses all 4 pairs, 8 conductors).
From my Krone Master Installers course and work at Akld Uni doing structured cabling.
However these are BIG networks, not your home variety.

Graham L
17-07-2005, 04:15 PM
When you use Cat5 or better, only two pairs are needed. 100BaseT4 was a short lived "standard".

For a nicer job, the thinwall black alkatene used for trickle irrigation is quite cheap.

To get a string in to pull the cable through (it does not push in for any length :( ) use a vacuum cleaner. Just tie a piece of rag which will form a "loose" plug in the hose to the string, and suck it through.

The only problem I can see is that ringing on the telephone will possibly put noise on the data pairs. That's why TCP/IP on Ethernet has error checking and repeats of packets. :D You'll never notice.

Pairs to use: it's up to you (as long as you use them in pairs, and use the same pairs at both ends). I'd use the colour code on the RJ45 to match the colours on pins 1&2, and 3&6 (which are the Ethernet pairs)..

personthingy
17-07-2005, 05:04 PM
Pairs to use: it's up to you (as long as you use them in pairs, and use the same pairs at both ends). I'd use the colour code on the RJ45 to match the colours on pins 1&2, and 3&6 (which are the Ethernet pairs)..OK, so lets assume that i get a 40 metre moulded cable so everything is factory standard.

I strip the outer insulation back, exposing 4 twisted pairs

Which coloured pairs coincide with 1&2, and 3&6, and therefore can not be cut?

Which coloured pairs are spare and therefore can be pulled sideways for alternative use?

Graham L
17-07-2005, 05:25 PM
Aha. You're going to cheat, intead of using sockets. ;)

Hold one end of the cable with the plug pointing up, and the latch facing away from you. The pins are numbered 1..8 from left to right.

You should be able to see the insulation on the wires through the transparent body of the plug. Each pair is "colour/colour+white". The pairs used by Ethernet are terminated on pins 1&2, 3&6. The spare pairs are on 4&5, 7&8.

If the cables have moulded on protective boots and they hide the wires, you will have to use less elegant methods. You must have a multimeter. ;) Attach a pin to one probe. You will be able to get one probe to the contacts on the plug, and use the pin to contact the wire through the insulation. Like all such jobs, this requires (at least) 4 hands. Drag the sprog away from his other occupations to do some work. ;)

personthingy
17-07-2005, 06:26 PM
Drag the sprog away from his other occupations to do some work. ;)Funny thing is he was just around, read this thread,got shown where the cable will be, and the work that goes into clearing the access, and he promptly went home to his mums :p

O well, this one can take as long as he wants it to drag it out to. Bet he'll get motivated when he realises that the only net access from here on in will be through the cable he helps put in place ...

Righto.. next steps, buy the cable, buy the irrigation tube, motivate Ziggy.....

Thanks for all your help.

CYaBro
17-07-2005, 07:29 PM
A normal CAT5e cable has 4 pairs of wires and depending on what standard has been followed, A or B, the colours will be, from pin 1-8, - Green/White - Green - Orange/White - Blue - Blue/White - Orange - Brown/White - Brown.
Both ends will need to be the same if plugging into a hub/switch and a PC.

If you want a crossover cable then one end will be as above and the other end will be - Orange/White - Orange - Green/White - Blue - Blue/White - Green - Brown/White - Brown.

The orange and green pairs are used for 10/100MB network data and the blue and brown are not used. (I have seen 10/100 cables without the blue and brown pairs of wires in them but this is not normal)
Normally you would use the blue pair for telephones as they are in the middle two pins of the plug just like a telephone RJ11 plug, which will fit into an RJ45 socket but not very snuggly.

You only need all 4 pairs of wires if you are running gigabit network switches.

personthingy
17-07-2005, 08:22 PM
Righto.. I think ive got this..

If i buy, or get made a STANDARD cable, i can connect it between the wee hub in the sleepout, and the uplink port of my as yet unbought network switch in the main house.

I can then strip the outer insulation back 200mm or so, and divert the blue/white and brown/white pairs and use one of them for the phone in Ziggys room and the other for something else...maybe.

This is something i look forward to.

Chris.

Graham L
18-07-2005, 05:21 PM
I strongly recommend looking at the plugs before cutting. The wires not to cut are those going to pins 1&2, 3&6. I have no faith at all in manufacturers following "standard" colour codes. Least of all when it "doesn't really matter" as in factory terminated cables, where the important thing is that pairs of wires are connected to the pairs of pins. I looked at a DSE cable last night. Despite the boots, the wire colours were visible.

BTW use a straight cable, not a crossover. You'll be using a hub at the far end, so that's what's needed anyway.

qyiet
18-07-2005, 06:39 PM
A while ago I brough a pre wired spliter for running 2x Ethernet connections down the same Cat5 cable.

I think worked with phone as well (we had a PABX and everything running through RJ45s) It might just be easier, and less error prone than doing the cutting and wiring yourself.

Here are a bunch of pre-wired options (http://www.cdynamics.co.nz/index.html?VS=sp&G=NC802)

Don't let me discourage you though.. It's fun :-)

-Qyiet