1
3920-A2-GK47-10
February 2002
COMSPHERE 3920Plus Modems
Model Number 3920-A2-xxx
Installation Instructions
Document Number 3920-A2-GK47-10
February 2002
Overview
The COMSPHERE Model 3920Plus modems are full-feature, high-speed leased modems, providing reliable
asynchronous and synchronous operation over leased or dial-line networks with data rates as high as 33,600 bps.
The COMSPHERE 3920Plus modem is available in several models. This document refers to model numbers in
the 3920-A2 series, which are singleport modems with single-rate power supplies. Modems in the 3920-A1 series
have universal power supplies and are described in the COMSPHERE 3900 Series Modems, Models 3920Plus
and 3921Plus, Installation Instructions, Document No. 3920-A2-GK41.
Through downloading capability, any Model 3920Plus modem is upgradable to the latest firmware, requiring no
new hardware investment or on-site personnel, with little or no downtime. For more information on downloading
capability, refer to the Automatic Firmware Download section in Chapter 3 of the COMSPHERE 392xPlus
Modems, Models 3920Plus and 3921Plus, Technical Reference Manual, Document No. 3920-A2-GH30.
NOTE: Do not download firmware with a release number lower than 4.0 to a Model 3920-A2-xxx modem.
Model 3920Plus modems support a wide range of modulation schemes and offer control using either AT
commands, the diagnostic control panel (DCP) or the optional COMSPHERE 6700 and 6800 Series Network
Management Systems (NMS). The NMS performs extensive monitoring, testing, reporting, and restoral functions
to assist in managing your network.
Model 3920Plus modems are compatible with a number of dialing methods and protocols, such as asynchronous
AT commands, CCITT V.25bis dialing, and the DCP. The DCP allows you to use the Model 3920Plus modem in
a variety of applications and environments while also providing control over modem configuration, dialing, and
diagnostics. The Model 3920Plus modems come with preset factory configurations that are the most often used
modem settings.
This document provides the following information:
•
A description of the 3920Plus modem
•
A list of equipment supplied with the modem
•
A list of customer supplied equipment
•
Installation instructions
•
A 392xPlus Menu tree
•
Important safety instructions
•
Regulatory notices
•
Government requirements and equipment return information
