E1and RJ48(C|X) cabling

I'm currently using RJ48C cables to connect an aculab card (Prosody
PCI) to a PBX to make calls, etc. via this. Unfortunately I've had
several problems with this, as the setup seems very fragile with
regards to physical strees as minor pushes, shortcircuiting cables,
etc has caused quite a lot of havoc. I was wondering whether there was
anything to do about this, and have a few questions
1) The wikipedia page
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"RJ48X is a variation of RJ48C that contains shorting blocks in the
jack so that a loopback is created for troubleshooting when unplugged
by connecting pins 1 and 4, and 2 and 5."
Would a RJ48X cable give earlier/more distinct warnings when state was
inspected through appropriate software (aculab callmanager)?
2) Is there a variation of Cat 5 cabling/RJ45 connectors that makes
it easier to fabricate the cables?
3) Where to buy the cables? A google search only turns up one company
in the U.S. Is the standard known by some other name in Europe? Or
does everyone make these cables themselves?
I'm amazed at how easy the setup breaks (say compated to standard
ethernet), so in general I'm wondering how other people handle this?
Reply to
Mads Ravn
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Maybe you have some really bad cables in general? Copper is copper. I've installed literally hundreds and hundreds of T1 circuits with basic voice-grade/cat3/cat5 cabling. Most patching was done with bog-standard ethernet patch cords. Cross connects were punched down on stock 66 or 110 blocks. I've used ABAM cabling a few dozen times, but got tired of sourcing it and dropped using it, and installations just kept working fine after a dozen years on voice-grade cabling.
RJ stands for registered jack (or many varients lost in time). A cable is not a jack, a jack is the thing you plug the cable into. There's no such thing as a RJ48X cable??? Anyway, the short is generally facing the telco side. Ie. you suspect the customer has bogus gear, you have them unplug it, now you have a hard loop back to you to test the circuit all the way to that jack.
RJ48X jacks went out quite a while ago, mostly after the telcos stopped being responsible for inside wiring at all (past their 90 day windows or whenever they'll warantee their inside work now-a-days).
?? Are you making your own patch cables? If you find it difficult, you shouldn't be making your own patch cables. Buy them premade from the factory. It sounds like alot of problems might go away then? Thats what the vast majority of the cable pros do, its not usually worth the time to make them when they are like a buck a piece (not going to BestBuy to spend $20 on something that costs less than a buck to make).
Thats probably because you are looking for something that doesn't exist. Nobody makes their own cables?
None of my hundreds of instalations ever break using stock ethernet cabling. I'd question what you are doing specificly to make it have a problem?
Reply to
Doug McIntyre
You're right, sorry for the abuse of terminology. If I understand you correctly what I want is a shielded cat5 cable with two RJ48c jacks crossover connected? Or a RJ48C crossover cable for short.
Ok. I thought this connector type might be helpful in diagnosing connection problems on our end.
Yes I am.
That is the plan now ... hence question 3.
We'll the cheapest I've found is @
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they sell a 3 ft. variety for $17.50. Only trouble is the shipping to Europe.
Not sure exactly what you mean.
I think the answer to that question is: Making my own (bad) cabling. I'm going to see if we continue having problems with the prefabricated variety.
Thanks for your reply,
Reply to
Mads Ravn
Okay, so you are hooking up two devices talking PRI locally? Rather than a telco handoff which would handle the cross as basic wiring.
Finding premade crossover T1 cabling will be a bit harder to find cost effective ones. They'll charge you heavily for doing something different. :(
Here's somebody that wired up some easy to punch jacks in a crossover pattern.
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Some google searched only found the $20 premade T1 crossover cables premade.. :(
You don't need shielded cat5. If anything, you want the pairs shielded against each other in a T1 cable, not shielded together into one bundle. (ie. an ABAM cable).
As I mentioned, almost all my installations will get wired up to a box or panel, and then patched over with bog-standard ethernet cabling. You could extend the concept of the cross-over box mentioned above to a set of two patch-panels if there are a lot of these runs, and not have to worry about doing up the cables.
Stonewall cable is not really all that cheap.
This is probably a straight through cable wired up to the pairs that T1 uses. Did you need the straight throughs? Or the cross-over T1 cables?
Reply to
Doug McIntyre
I don't know if they are related, but RJ38X is similar, but the shorts are (1,4) and (5,8). They are commonly used for alarm systems that connect to the phone line. That allows the alarm to have priority over the phone line when needed, but if unplugged then house phones work normally.
-- glen
Reply to
glen herrmannsfeldt
For T-1/E-1 cabling try here also
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they have Authorized Distributors in these countries
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