DECrepeater 90T & DECrepeater 90T+ Owner's Manual

This document is the Owner's Manual for the Digital Equipment Corporation's DECrepeater 90T and DECrepeater 90T+, published in December 1992.

The manual describes these devices as 9-port Ethernet repeaters designed for IEEE 802.3 CSMA/CD networks, featuring one ThinWire (10Base2) port and eight twisted-pair (10BaseT) ports. A key distinction is that the DECrepeater 90T+ supports both shielded and unshielded twisted-pair cable, while the 90T supports unshielded only.

These repeaters can function as standalone units (unmanaged) or as managed units when installed in a DEChub 90 backplane with a DECbridge 90 series bridge.

The manual provides comprehensive information on:

• Overview and Features: Description, features, and identification of LEDs and connectors.
• Configuration Rules: Guidelines for segment lengths and network constraints for IEEE 802.3 LANs.
• Installation: Instructions for standalone (desktop or wall-mount) and backplane installation in a DEChub 90.
• Management: How to manage the repeaters on a network using the Maintenance Operations Protocol (MOP) via VMS or ULTRIX systems, including command language, management techniques, and error messages.
• Troubleshooting: Guidance for diagnosing issues with both standalone and backplane installations based on LED indicators and error messages.
• Specifications and Parts List: Detailed physical, environmental, and power specifications, as well as MJ pin assignments and a list of replacement parts.