DigiTech C0408 Common Equipment DESCRlPTlON, Station Description, Model CO/PBX Station Capacity

. ..a. au-u83 System Overview

SECTION 3

HARDWARE SUMMARY

The digital telephone system consists of an electronic Key Service Unit (KSU) base unit, usually referred to as common equipment, optional expansion modules to extend station and line capacities as required, a software cardridge containing the operating System programming, dedicated digital electronic key telephones, and interconnecting wiring consisting of small, 2-- or 4--conductor, twisted-pair cable.

The station and line capacity of the base unit and optional expansion module are per the following chart.

MODEL	CO/PBX		STATION
NO.	CAPACITY		CAPACITY
CO408	4		8
C O 8 1 6	8		1 6
Cl 632	1	6	3 2
C M 4 0 8	4		8

The digital telephone system is full featured, and supports the digital telephone models.

The digital system is expandable in both line and station capacity with the addition of add-on expansion modules. Refer to Figure 3-14on page 3-24 for an illustration of the expansion configurations.

COMMON EQUIPMENT DESCRlPTlON

The common equipment base unit is a fully electronic device. It is essentially a special purpose computer system acting as a communications controller between central off ice (CO), private branch exchange (PBX), or CENTREX supplied lines and the proprietary digital telephone stations. The software architecture of the common equipment provides complete system support and great flexibility of operation.

The system is fully digital and is ISDN up-gradable with two usable time slots available for each station. The digital information passes over time division multiplexing (TDM) highways. The digital information is an encoded version of the voice transmission and control signals that are translated into computer language. The TDM highway can transmit several signals over a single pair of wires at the same time. The signals are governed by a system clock. This clock creates an overall point of reference against which the TCM information is synchronized and partitioned into time slots. A time slot is a portion Of time assigned to a particular position of the system clock. Each time a particular clock position iS reached, the information associated with that position

can be read. As the system clock goes through the clock cycle, all necessary digital information is passed between the pieces of equipment sharing the highway.

The common equipment consists of a base unit, which provides complete feature support, and optional expansion modules which provide extended station and line coverage.

The wmmon equipment is contained in a functional, modem-style metal housing of contemporary design in keeping with the needs of the modem off ice environment. It is engineered to be wall or rack mounted. The outline dimensions of the common equipment base units are illustrated in Figure l-l.

STATION DESCRIPTION

The digital telephone stations employed with the digital system are electronic, microprocessor- controlled, devices. They allow not only multiline pickup but also single key access to features available from the serving CO, PBX, or CENTREX switch as well as the wmmon equipment. The digital telephone is available in two different images. The features of the images are as listed below and as detailed in Figure l-2 and in Figure l-3.

The wide-image digital telephone provides the following features:

•Full modular connection

•3 fixed buttons with indicators

. SPKR • HOLD

. ITCM

3 fixed buttons without indicators • TAP

. TRANS/CONF

. MUTE

Programmable buttons with indicators 7-foot, G-conductor line cord

6 position, 4- or 6-conductor modular line jack K-type handset (hearing aid compatible)

Ringer volume control (Off, Low, and High) Wall mounting capability