ADTRAN DSX-1 User Manual page 8

Chapter 1. Introduction
4
represents the slot number, and the .1 indicates the port
number. For the TSU 100/600 application, there is only
one option slot. Therefore the port designation for the
Passthru port is 1.1. If added, the Nx56/64 port
designation would be 1.2. These port numbers appear
in the front panel LCD menu displays.
DSX-1 Passthru Option Module 61200.055L1-1C