AT&T DEFINITY 555-230-761 Generic 1 3 System 75 8403 Voice Terminal User's Guide

AT&T DEFINITY 555-230-761 Generic 1 3 System 75 8403 Voice Terminal User's Guide

This is the official AT&T DEFINITY Communications System 8403 Voice Terminal User's Guide, publication number 555-230-761, Issue 1, dated August 1993. The guide covers the features of the 8403 voice terminal as used with the AT&T DEFINITY ECS, DEFINITY Generic 1, DEFINITY Generic 3, and System 75 PBX platforms, and provides step-by-step procedures for operating those features.

Specifications & What's Included

• Publisher: AT&T
• Publication Number: 555-230-761
• Title: DEFINITY Communications System — Generic 1 and Generic 3 and System 75 8403 Voice Terminal User's Guide
• Issue: Issue 1
• Publication Date: August 1993
• Format: Printed softcover booklet
• Language: English
• Compatible Systems: AT&T DEFINITY ECS, DEFINITY Generic 1, DEFINITY Generic 3, AT&T System 75
• Compatible Terminal: 8403 Voice Terminal
• Quantity: 1 copy (multiple copies visible in photos; one copy per order)

Applications

The AT&T DEFINITY Communications System was a major enterprise PBX (Private Branch Exchange) platform introduced in the 1980s and widely deployed through the 1990s in mid-to-large business and institutional environments. The DEFINITY Generic 1, Generic 3, and System 75 variants served organizations ranging from small offices to large campuses, providing internal voice switching, call routing, and a range of telephony features. The 8403 was a multi-line analog/digital voice terminal (desk telephone) designed for use with these systems, offering access to features such as call transfer, conferencing, hold, and programmable buttons. User's guides like this one were distributed to end users and administrators so they could learn feature access codes and operating procedures. This guide dates from August 1993, placing it squarely in the era when DEFINITY systems were at the height of their deployment. It remains a practical reference for organizations still running legacy DEFINITY hardware, for technicians servicing or decommissioning these systems, and for telecom historians and collectors.