vii3920-A2-GN31-30 November 1996
Preface

Objectives and Reader Assumptions

This
manual describes how to install and operate the COMSPHERE
r
Model 3920
Plus
standalone
and Model 3921
Plus carrier
-mounted modems. Users of this manual must have a basic
understanding of modems and their operation.

How to Use This Manual

Chapter 1 provides technical specifications, information about the four 392xPlus
models, the
modem features, and the government requirements for using these modems.
Chapter 2 provides instructions for installing the 392xPlus
modems.
Chapter 3 provides the information required to operate the Model 3920Plus
using the diagnostic
control panel and the Model 3921Plus using the COMSPHERE 3000 Series Carrier’
s shared
diagnostic control panel (SDCP).
Chapter 4 provides the information required to set configuration options in the 392xPlus
modems
using the modem’
s diagnostic control panel.
Chapter 5 provides instructions for using A
T commands and S-Registers.
Chapter 6 provides instructions for using the Dial Access Security feature.
Appendix A provides a menu tree for the 392xPlus
modems.
Appendix B provides instructions for performing diagnostic tests when data communication
problems occur.
Appendix C provides EIA-232-D and VF TELCO pin assignments.
Appendix D provides V.25bis dialing information.
Appendix E provides an ASCII translation chart.
Appendix F provides a list of all default configuration options available for the factory preset
configurations.
Appendix G provides diagrams of sample configurations for the 392xPlus modems.
Appendix H provides an equipment list for the 392xPlus
modems.
The Glossary provides a description of terms used throughout this manual.