Ositech comm 614006-001 - Manual (Page 17)

User’s Guide and Reference 2 - 9
Hardware Installation
If you are using extended length segments, all repeaters and transceivers
must be designed for 300-meter operation. In addition, all LAN adapters
must be configured to operate with the extended segment length.
Note: You cannot use Ethernet adapters to extend 185-meter segments to
300-meter segments unless all LAN adapters and repeaters in the
network are capable of operation on the extended segment length.