Cabletron Systems MR-9T Installation Manual page 19

Connect the other end of the twisted pair segment to any port on
the front of the MR9T.
If you are using MR9T Port 9, make sure that the configuration
switch on the side of the MR9T is set correctly, either cross-over
(X) or straight-through (=). If you are unsure of the proper
setting for your application, check the pin configurations of the
RJ-45 ports at each device to be connected. Make sure that you
are connecting TX+ to RX+, TX- to RX-, RX+ to TX+, and RX- to
TX-. Normally, for a connection between the repeater and a
network hub, you would use the straight-through configuration.
If you are using any of Ports 1 through 8 for your network
connection, you must use a twisted pair segment that internally
swaps the signal pairs to maintain the TX to RX configuration
2. To connect an MR9T-C via the BNC connector, connect one end
of a thin coax segment to the repeater and the other end of the
cable to a 10BASE-2 network hub. Both ends of the cable must
be terminated with a 50 ohm terminator. On the MR9T-C you
can select the internal 50 ohm terminator by setting the TERM
switch to the ON " " position. Or you can turn the internal
terminator OFF " " and connect the coax cable with a tee
connector and external 50 ohm terminator.
Caution: If you use an external terminator, be sure that the
repeater's internal terminator is turned off. Double termination can
cause unstable network operation.
3. Check that the LNK LED for the connected port is lit. If the LED
is not lit, perform each of the following steps:
a. Check that both the repeater and the network device at
the other end of the cable segment are turned on.
b. Disconnect the cable segment that connects the repeater
to the network hub.
c. For an RJ-45 connection, check the RJ-45 connectors for
proper configuration. The MR9 configuration is listed in
Chapter 2. If you are using MR9T Port 9, check the cross-
over switch to ensure that it is in the proper position.
d. Check the cable for continuity.
INSTALLATION
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