Port Circuits
The following port circuit packs provide the link between trunks and external equipment and the TDM bus:
●Analog Line (TN742)
●ATL Line (ZTN79)
● Auxiliary Trunk (TN763)
●Data Line (TN726)
●DID Trunk (TN753)
● Ground Start Trunk (ZTN76)
●Loop Start Trunk (ZTN77)
●MET Line (TN735)
● STARLAN Interface (ZTN84)
●Tie Trunk (TN760B)
●Tip Ring Line (ZTN78).