Specifications

Table Of Contents
Data Modules
21-46 Issue 11 December 1999
Figure 21-15. A Block Diagram of 703A Data Service Unit Interfaces
Applications
The 703A DSU can be used with 7406D voice terminal connected to the
DEFINITY Communications System Generic 1, Generic 2, Generic 3, the
DEFINITY ECS, System 75, or System 85. Typical applications are users with
data terminals requiring a large number of features.
Physical Description
Features
Option switches
The option switches for setting the operating speeds, disconnect sequence, and
parity are located on the bottom of the DSU.
Self-Test button
The Self-Test button is located on the rear of the data stand adjacent to the
RS-232-C connector. It is recessed and can be depressed with a pointed object
such as a straightened paper clip.
Data
Terminal
Data
Service
Digital
RS-232C
Unit
DCE
Digital
Voice
Term inal
DCP
Switch
Digital
Line
Port
DTE