Nortel NTBX21BC (OPTera Metro / PDH-SDH / Passport-MSS / networking portfolio) Telecom System Card / Module

The Nortel NTBX21BC is a DMS-100 Line Card (LC), a peripheral circuit pack from the NTBX line-card family used in Nortel’s DMS-100 digital central-office switch to terminate subscriber lines at the line concentrating module (LCM) or remote line shelf. It provides the electrical interface and signalling between the copper subscriber loop and the switch’s digital fabric, drawing on the same NTBX card family as the platform’s ISDN and specialty line variants. DMS-100 offices of this generation remain in service at telephone operators worldwide, and genuine spares like this restore full line capacity after a card failure or support planned line growth. Specifiers should confirm exact frame, shelf and generic-program-load compatibility before ordering. Tech-Star is UK-based and ships worldwide. Contact our sales team for current availability and pricing.