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Raleigh, NC
reply to bbwithdrawls

Re: [HELP] Need help determining errors

The problem with techs... they're kind of lazy. They'll run all 1's and all 0's and declare a circuit "not broken". I would mark it down to "lack of training", but these people have been doing this job long enough to know how to use the other 2 dozen tests the T-Berd can run. Repeat after me children: Two to the twenty one quasi-random!

The more hops in the circuit, the more places there are for someone to have a jumper/dipswitch wrong. The only way to find it is to test from *every* junction. To both ends of the circuit.

(I had one case where jpg's wouldn't go across the circuit: one of the wires was broken... a 3 wire T1 won't do! The next was a line card set for D4(SF) in the path: I'm not sure how that ever worked as D4/B8ZS isn't a valid configuration.)


D4/B8ZS is rare but valid. I have a customer with about a dozen Voice T1s into ancient Mitel PBXs that are configured for D4/B8ZS. The circuit will work if your DF/EFS or AMI/B8ZS is in correct but you will end up with slips and strange, random trouble tickets that will make you pull your hair out.
I do not, have not, and will not work for AT&T/Comcast/Verizon/Charter or similar sized company.


You would have to be going through one weird dacs to be running anything other than esf/b8zs on a data-only T1 in 2012. Please post some show controler t1 output for us to argue over =)


These are circuits that are between an Adtran TA900 and the customer's PBX that replaced T1s that were once point to point T1s back into another carrier's 5ESS. It took some time to figure out this combination because the original phone vendor was no longer around and it took trial and error to discover this because the circuits would take errors and slips.

There is no reason why this would not work but there is no reason to do it unless there is some limitations on old equipment. Most of the PBX's that were installed with this configuration were put into service in the early 90's when PRIs and PRI cards were considerably more expensive than T1's. None of these PBX's can utilize Caller ID name even with a PRI and only a few of them will take Caller ID number using Feature Group D.
I do not, have not, and will not work for AT&T/Comcast/Verizon/Charter or similar sized company.