The T1 ESF CSU is a full-featuredT1 Channel Service Unit used to connect T1data terminal equipment (DTE) such as a PBX, switch or channel bank to T1 facilities. Capable of interfacing to both B8ZS and AMI circuits, theT1 ESF CSU can convert signal formats or line code to integrate older equipment. The ESF CSU is designed to provide alarms, loop backs, signal regeneration, line build-out, and surge protection, while maintaining 1’s density for the DTE and T1 network.