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What's a B1 line and a J-Circuit?
- Thread starter netchaser
- Start date
It's probably not a "B1" circuit. rather, the phone techs will often refer to an analogue phone line (POTS line) as a "1B" circuit.
Think of it this way, when you are dealing with distribution of phone lines, they are provisioned, somewhere upstream of you, as a channelized T1 (or larger) line. Another, unambiguous, way to refer to a T1 is as a 24B+D. Thus, a 1B is a single 64K B channel that has been provisioned by the carrier to your prem, most commonly, as an analogue voice line.
A J circuit is just a pair of wires in the CO jumpering an incoming pair from one prem to an incoming pair from another prem. No problem if all your premises terminate at the same CO. Bigger problem if they don't.
Cheers!
Think of it this way, when you are dealing with distribution of phone lines, they are provisioned, somewhere upstream of you, as a channelized T1 (or larger) line. Another, unambiguous, way to refer to a T1 is as a 24B+D. Thus, a 1B is a single 64K B channel that has been provisioned by the carrier to your prem, most commonly, as an analogue voice line.
A J circuit is just a pair of wires in the CO jumpering an incoming pair from one prem to an incoming pair from another prem. No problem if all your premises terminate at the same CO. Bigger problem if they don't.
Cheers!
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