Specifications

OVERVIEW LBI-39000B

1. OVERVIEW

This manual contains installation and maintenance information for the Enhanced Digital Access Communications System

(EDACS) Jessica Private Branch Exchange (PBX) Gateway, known simply as Jessica. Jessica works as a centralized

subsystem within an EDACS Multisite Network to allow interconnect calls to the Public Switched Telephone Network

(PSTN) or PBX by EDACS users, as well as calls to EDACS users from the PSTN/PBX. For calls originating from a

telephone, Jessica represents a single point of entry to every site in an EDACS network.

Figure 1 - Jessica PBX Gateway Functionality

Jessica incorporates the Ericsson MD110 PBX. A default or “standard” configuration for the MD110 tailored for Jessica

is provided; however, those installing Jessica must modify the MD110 configuration to meet the customer-specific MD110

requirements. A questionnaire on the MD110 configuration (refer to Appendix A of LBI-39039) should be completed by the

customer and provided to the installer of the MD110 minimally 2 weeks in advance of the MD110 installation.

Jessica provides common telephone features (such as common speed dialing) to EDACS radio users and those persons

calling into EDACS from the PSTN. Standard ringing and busy tones are incorporated on both inbound (telephone-

originated) and outbound (radio-originated) calls.

SCAT

Simulcast

To/From PSTN

or customer PBX

Level 1

RS-422

DACS Sites

Basic EDACS

Audio

IMC/CEC

JESSICA

Single Point of Entry For Routing

Telephone Calls Between the EDACS

Radio Network and the

Public Telephone Network

Downlink