TruePulse is searching for NT5A13BE, NT5A14AB and NT5A18AE circuit packs for the Nortel DNX-100, or as it was called back then: the Northern Telecom DNX-100. Any chance that you have one of these antiques?
The DNX-100 was one of Nortel earlier Digital Cross-Connection Systems, of the similar vintage as the Nortel FD-565. The system has long been discontinued. It is not one of the Nortel optical transport product platforms supported by Ciena.
The NT5A13BE, HECI code T1DAZ8B, is a DNX-100 Enhanced Memory card
The NT5A14AB, HECI code T1DAZ8D, is a DNX-100 Control Processor card
The NT5A18AE, HECI code T1DAZ7B, is a DNX-100 Admin card
Updated April 28, 2020