T1/LS on embedded T1/E1 trunk module

[acejavelin]

I have a customer with an unusual older T-1, which has to stay this way for while, right now it is connected to an old NSU and functioning proper... it is a T1/ESF (not PRI) that is running in T1/LS Trunk mode with separate numbers on each of the channels. I tried moving this circuit to an embedded dual T1/E1 module, duplicating the programming of the NSU in the 3300 on the T1/E1 module and could not get the trunks to work. The T1 would sync up but the channels would show as out of service no matter what I did.

Anybody have any experience with this type of setup on a newer T1/E1 card, is it even supported?

The only reason this is an issue is since they upgraded to 6.0SP1 they have issues with echo on those trunks only, so they want to do away with the NSU and use the dual T1/E1 card that is sitting idle in the controller, thinking it might help the echo issues.

[jrg0852]

So, there's no "D" channel, all are "B" channels (24)? I'm sorry but not familiar with this kind of circuit.

[ralph]

This goes way way way way back so I'm not sure if I remember it correctly.
If I remember there was something about a LS circ on a T1.
For grins, take a channel and program it as an E&M trunk.
Set the start type to immediate.

Ralph

[acejavelin]

Yeah, its pretty old technology and Ralph is correct, its a way of delivering a "loop start" trunk over a T-1 channel... I'll give that a shot.

And yes, jrg0852, you are correct, this is a 24 channel circuit, no B or D channel, not a PRI... old school T-1, in this case, really old school.