Originally posted by tommyb52:
Got stumped today.What would cause 4 ground start lines which are testing ok at the demarc, but when they go into the subs NEC PBX the lines are "picked up" but when you try to enter an extension,you hear the buttons beep but you aren't directed anywhere.You are defaulted to the operator who then connects you through.This is happening only on 4 lines out of more ground start lines going into the PBX.The NEC tech changed some cards but to no avail.Could DTMF be an issue?If so how is it tested?How or who can see it and adjust it?The switch is a DMS100.Any help is greatly appreciated.
Are you using Ground Start Trunks for Incoming? When you say the lines are "picked up" but you aren't directed anywhere - are you trying to call in and reach an extension?
I ask this because in all the years I worked on PBXs, Incoming trunks were either:
A) DIDs, which are loop start or
B) E&M which are loop start (well they're not Ground Start) or
C) Analog ICTs, which were also Loop Start
I'm sure that Incoming Trunks could be Ground Start, but I never saw one. Maybe these are supposed to be Out Going Trunks?
If I'm misunderstanding you then please correct me. If these are OGTs and you can't dial out then I would agree with the other guys and say - definitely a polarity reversal.
Try a quick and dirty (and easy) test. Reverse the polarity of the line, reconnect it and test it.
Sam
