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Steve40th

join:2013-02-24
Goose Creek, SC

AT&T green data cable. Is this the same one?

Phone Cable, RJ11 (6P4C) for data
»www.monoprice.com/products/produ···at=6#faq


ILpt4U
Premium
join:2006-11-12
Lisle, IL
kudos:9
Reviews:
·AT&T U-Verse
No, that is an untwisted pair phone cable/"flat satin" phone cord (basically a standard phone cord)

The U-Verse green Data cable has standard RJ-11 ends, but the wire inside the sheath is twisted pair cat 5 (2 pairs in most cords)

How long of a cord do you need?

The online AT&T equipment store lists a 14 ft cat 5 data cord with RJ-11 ends: »www.att.com/equipment/accessory-···q_model=

nephipower

join:2012-02-20
San Antonio, TX
said by ILpt4U:

No, that is an untwisted pair phone cable/"flat satin" phone cord (basically a standard phone cord)

The U-Verse green Data cable has standard RJ-11 ends, but the wire inside the sheath is twisted pair cat 5 (2 pairs in most cords)

How long of a cord do you need?

The online AT&T equipment store lists a 14 ft cat 5 data cord with RJ-11 ends: »www.att.com/equipment/accessory-···q_model=

ILpt4U, I don't know if you looked at the cable careful enough that Steve linked to. I don't know for sure if this is the correct cable but it looks like it to me.

What I do know is that it doesn't matter at all that it isn't a cat5 cable because even when a tech uses cat5 for a homerun install by default two out of the four pairs in the cat5 go completely unused.

So what is the difference if you use an untwisted pair that is just two pairs by defaults? Wires are wires right? As long as they can conduct energy i think that is what matters.

I have made many of my RJ45 cat5e cables for my home and all the difference is between a straight through, crossover, and even a console cable (which is used for configuring things like a Cisco router) is the order of the pairs of wires.

So I don't see why it would be any different for a "data" phone cable that is needed for uverse.


ILpt4U
Premium
join:2006-11-12
Lisle, IL
kudos:9
Reviews:
·AT&T U-Verse
In some situations it may not matter, but the twist in twisted pair does help the VDSL2 data signal, or other data signals. Something about the twist being able to help the signal transmit better (I admit, the exact physics of twisted vs untwisted pairs is not my strong suit)

The number of pairs in the listed cable is irrelevant. A single pair cable would be fine. The relevance is whether said pairs inside the cable/cord are twisted

100 Mbps ethernet does not work very well on 2 untwisted pairs. Have I seen it run on untwisted red/green/yellow/black phone wire? Over a short distance, yes. But it will not work up to the Ethernet standard with Cat 5 to 100 meters (I think 100 meters is the standard's max)

In my own experience, I have seen poor xDSL performance using standard flat satin untwisted phone cords for the link from jack to modem. I have also seen it work just fine

AT&Ts standard for technicians is a Cat 5 data connection, from NID to Modem, which includes the patch cord. And every data patch cord sent with an U-Verse self install modem also includes a Cat 5 data cord with RJ-11 ends for the link from jack to modem

GusHerb94

join:2011-11-04
Chicago, IL
kudos:1
The one and only time I ever connected a flat 2 pair phone cord to our ADSL modem (at the time) it went wonky and wouldn't stay connected for more then a minute. Plugged it back in and poof, like magic it worked fine again. It is very possible that was the final straw in the camels back, as the inside wiring was all untwisted two pair, with very bad splicing at that time as well.

It is kinda funny that it's standard to run Cat5e from the NID to the DSL modem, yet all the wiring between the NID and CO, RT, VRAD etc is Cat3 at best.


dahan

join:2000-10-25
Leander, TX
reply to nephipower
said by nephipower:

ILpt4U, I don't know if you looked at the cable careful enough that Steve linked to. I don't know for sure if this is the correct cable but it looks like it to me.

No, the wire colors are wrong--by convention, the wires in twisted pair cables are colored to show which wires are twisted together: one wire of the pair is a solid base color, and the other wire is that base color plus a stripe. E.g., orange/orange-white, or blue/blue-white. Whereas flat untwisted cables are solid red, solid green, solid black, solid yellow, etc... with no coloring that indicates any sort of pairing. So that cable isn't a twisted pair cable. Or you can also tell by the description, which says that it's a "Flat Cable".

As for why that matters...

So what is the difference if you use an untwisted pair that is just two pairs by defaults? Wires are wires right? As long as they can conduct energy i think that is what matters.

Wires aren't always just wires. I doubt if twisted pair cables would even exist if there wasn't any reason for the twists... In this case, the wires make up a transmission line. And the twisted pairs help block out external radio frequency interference. If the pairs weren't twisted, the wires would act as an antenna and pick up radio transmissions. That's fine for POTS, since people can't hear radio frequencies, but not fine for *DSL, where the modem can, and is listening to frequencies that are in the AM radio band. Even twisted pairs can't get rid of all interference... occasionally, someone will post a bitloading graph that shows a notch where a strong AM radio station is.

nephipower

join:2012-02-20
San Antonio, TX
I never said that the cable linked to on monoprice was a twisted pair cable. But I totally understand the need to have it for Uverse install and you guys reminded me that twisting helps out a lot to filter out outside interference.

So if we would like to make our own data cable for an install from the RJ11 jack to the RG, does anyone have a color guide for how to wire it?

If someone wants to make lets say a 25 ft RJ11 cable from cat5e I think this would be some useful information to know.


ILpt4U
Premium
join:2006-11-12
Lisle, IL
kudos:9
Reviews:
·AT&T U-Verse
said by nephipower:

So if we would like to make our own data cable for an install from the RJ11 jack to the RG, does anyone have a color guide for how to wire it?

If someone wants to make lets say a 25 ft RJ11 cable from cat5e I think this would be some useful information to know.

Take a lenght of Cat 5 or higher, strip back the outer sheath.
Take any one of the (usually 4) pairs (blue/blue-white would be most standard, but any of the four pairs is ok - orange/orange white, green/green-white, or brown/brown-white are the other 3 pairs).
Terminate your 1 pair to the "middle" pair of a 4 or 6 pin plug (pins 2&3 if 4 pin, pins 3&4 if 6 pin). Standard practice would be the "color"/ring wire of the pair to pin 2 in 4 pin, or pin 3 in 6 pin (blue wire if using the blue/blue-white pair), and use the "white"/tip wire to pin 3 in 4 pin, or pin 4 in 6 pin (blue-white wire if using the blue/blue-white pair)
Crimp your plug with a RJ-11 crimper
Repeat the steps on the other end of your cable

Most important is that the pair and pattern is followed on both ends


ILpt4U
Premium
join:2006-11-12
Lisle, IL
kudos:9
Reviews:
·AT&T U-Verse
reply to dahan
said by dahan:

No, the wire colors are wrong--by convention, the wires in twisted pair cables are colored to show which wires are twisted together: one wire of the pair is a solid base color, and the other wire is that base color plus a stripe. E.g., orange/orange-white, or blue/blue-white. Whereas flat untwisted cables are solid red, solid green, solid black, solid yellow, etc... with no coloring that indicates any sort of pairing. So that cable isn't a twisted pair cable. Or you can also tell by the description, which says that it's a "Flat Cable".

Conventionally, yes I agree that using blue/blue-white (pair 1), orange/orange-white (pair 2), green/green-white (pair 3), and brown/brown-white (pair 4) typically indicates twisted pair, and using red/green (pair 1), yellow/black (pair 2), blue/white (pair 3), orange/brown (pair 4) typically indicates untwisted pair

But from my experience, that is not a hard rule. I have seen Cat 3 and even Cat 5 using the red/green/yellow/black/blue/white/orange/brown coloring scheme (not very often admittedly), as well as untwisted cables using the blue/blue-white orange/orange-white color scheme


ILpt4U
Premium
join:2006-11-12
Lisle, IL
kudos:9
Reviews:
·AT&T U-Verse
reply to GusHerb94
said by GusHerb94:

It is kinda funny that it's standard to run Cat5e from the NID to the DSL modem, yet all the wiring between the NID and CO, RT, VRAD etc is Cat3 at best.

I agree, to a point. The plant wire from CO to Crossbox to VRAD back to Crossbox to your terminal/pedestal is Cat 3 at best (typically -- some VRAD to Crossbox wire is actually Cat 5, but that is usually only 100-200' or so), but those plant cables are also shielded, with the shield bonded to ground, which also helps reduce interference.

A buried drop from your pedestal to your NID is also shielded, and there is also shielded aerial drop (but admittedly, most aerial drop is unshielded). Those cables are typically Cat 3 or better, but not usually Cat 5. But again, those shielded cables are also bonded to ground, which also helps fight interference

Most Inside Wire cables are unshielded, so a tighter twist is more critical in reducing interference. There is shielded IW out there, but it is not used very often, and when it is, that shield also needs bonded to ground

GusHerb94

join:2011-11-04
Chicago, IL
kudos:1
said by ILpt4U:

said by GusHerb94:

It is kinda funny that it's standard to run Cat5e from the NID to the DSL modem, yet all the wiring between the NID and CO, RT, VRAD etc is Cat3 at best.

I agree, to a point. The plant wire from CO to Crossbox to VRAD back to Crossbox to your terminal/pedestal is Cat 3 at best (typically -- some VRAD to Crossbox wire is actually Cat 5, but that is usually only 100-200' or so), but those plant cables are also shielded, with the shield bonded to ground, which also helps reduce interference.

A buried drop from your pedestal to your NID is also shielded, and there is also shielded aerial drop (but admittedly, most aerial drop is unshielded). Those cables are typically Cat 3 or better, but not usually Cat 5. But again, those shielded cables are also bonded to ground, which also helps fight interference

Most Inside Wire cables are unshielded, so a tighter twist is more critical in reducing interference. There is shielded IW out there, but it is not used very often, and when it is, that shield also needs bonded to ground

Shielding doesn't prevent interference internal to the cable though, and it seems there's alot of that going on with VDSL etc.

In my neighborhood, when we had Uverse it was hard for the guys to find us a pair that had minimal enough interference to provide a reliable connection. Some techs had gone through somewhat extensive lengths to check pedestals remove bridge taps, re do splices etc but it all came down to interference, from neighboring pairs with Uverse services on them.

It was really quite frustrating that it was that hard just to find a good line at just 2,000 feet from the VRAD. Anyways, all this I was told because of the fact that the wiring was just Cat3. Not very old either.


CarbonCopy

join:2003-01-29
Fresno, CA
reply to Steve40th
These should work even though they don't reverse polarity.
»www.cablesondemand.com/category/···UNNE.htm


ATTek
Got Sand?
Premium
join:2000-12-13
Glendora, CA
Polarity is irrelevant anyway
--
What does THIS button do.....