Paradyne 392xPLUS operation manual Model 3921Plus Carrier-Mounted Singleport Modem

COMSPHERE 392xPlus Modems

Model 3921Plus Carrier-Mounted Singleport Modem

The Model 3921Plus is a carrier-mounted singleport modem (Figure 1-2) capable of either

4-wire/2-wire leased-line or dial operation. The modem installs into a COMSPHERE 3000 Series Carrier, occupying a single slot. The modem's faceplate has sixteen (16) LED status indicators for displaying modem activity and an audio speaker jack for the carrier's optional speaker.

The modem's back panel has two edge card connectors that mount into a connector plate. This connector plate has two DB-25-S connectors, one providing an EIA-232-D DTE interface and one for future functionality.

Model 3921Plus Carrier-Mounted Multiport Modem

The Model 3921Plus is a carrier-mounted multiport modem (Figure 1-3) equipped with an integral time division multiplexer (TDM) with a modem sharing device (MSD). The modem installs into the COMSPHERE 3000 Series Carrier, occupying two slots. The modem's faceplate covers two slots in the carrier. It has twenty (20) LED status indicators for displaying modem activity and an audio speaker jack for the carrier's optional speaker.

The modem's back panel has four edge card connectors that mount into two connector plates. Each connector plate has two DB-25-S connectors providing four EIA-232-DTE interfaces.

Both the singleport and multiport Model 3921Plus modems derive ac power from the COMSPHERE 3000 Series Carrier's backplane, which is a common bus to all devices installed in the carrier. The user interface to any Model 3921Plus modem is through the shared diagnostic control panel (SDCP), an optional feature which operates in a manner similar to the DCP on the Model 3920Plus modems. For a better understanding of DCP operation, refer to Chapter 3, DCP Operation.

1-4 November 1996 3920-A2-GN31-30