Installation manual

If any hardware components are damaged, notify your sales representative. Return equipment using the

procedures described in the Government Requirements and Equipment Return section.

Customer-Supplied Equipment

The following customer-supplied equipment is required to complete a data communications system using the

Model 3910 modem:

• A DTE with an available EIA-232-D serial port.

• A standard EIA-232-D cable with a DB-25-P (plug) connector at one end to attach to the modem.

• One of the following modular leased or dial network interfaces:

— JM8 for leased-line applications.

— RJ11C for dial permissive applications.

The following customer-supplied equipment is required for the installation of a Model 3911 modem:

• A COMSPHERE 3000 Series Carrier.

• A 50-pin mass termination cable.

• One of the following modular or 50-pin leased or dial network interfaces:

— RJ11C for single line dial permissive applications

— RJ21X for multiple line dial permissive applications

— 66 punchdown block

• One Network Interface Module (NIM) for modems installed in Slots 1–8 and one NIM for modems

installed in Slots 9–16 (required for dial-line applications).

For installation of the COMSPHERE 3000 Series Carrier into a cabinet, refer to the COMSPHERE 3000 Series

Carrier, Installation Manual, Document No. 3000-A2-GA31.

Model 3910 Input Voltage Requirements

The power supply used with the Model 3910 modem (Figure 1) is auto-sensing and capable of operating (without

restrapping) with input voltages from 100 Vac to 250 Vac, and input frequencies from 50 Hz to 60 Hz.

Model 3910 Modem Installation

Before installing your standalone modem, make sure your installation site is clean and well-ventilated. Allow

space around the modem for installing cables and telephone cords, and make sure the modem is located within

reach of the ac power outlet. The distance between your modem and DTE should be minimized if DTE data rates

exceed 19,200 bps. Also, low capacitance cables may be necessary for speeds greater than 19,200 bps or distances

greater than 50 feet.