3com 8 用户手册

下载
页码 40
13
Connecting Hubs Using 10BASE-2
Connect a 10BASE-2 ‘Y’ piece to each of your hubs 
(Hub 4C only). Connect the ‘Y’ pieces with 10BASE-2 cable 
to form a single segment, as shown in Figure 4. Remember 
to terminate the two free ends of the segment by fitting 
terminators (end pieces).
To disconnect a 10BASE-2 cable, twist each connector 
counter-clockwise to unlock it, and remove it.
If you have connected a 10Mbps Ethernet transceiver 
to the AUI port, the 10BASE-2 port will be disabled. 
You can use this transceiver to connect your hubs but 
we recommend that you connect your hubs using 
10BASE-T cable (refer to the next section).
When using 10BASE-2 cable, it is important that both 
ends of the segment are properly terminated with 50 
Ohm terminators (end pieces).
Only use 50 Ohm 10BASE-2 cables and a ‘Y’ piece for 
each hub. You can use ‘T’ pieces but ‘Y’ pieces 
provide optimum clearance of the other ports.
Checking Connections
When you have connected your hubs, power them on. 
The Port Status LEDs for the 10BASE-2 ports you have used 
should be off. If they are not, check your connections.
Figure 4   Correct Hub Connections Using 10BASE-2
50 Ohm
terminator
10BASE-2 50 Ohm cable.
Minimum length of
each cable is 0.5m (1.6ft)
Maximum segment length is 185m (607ft)
(from terminator to terminator)
‘Y’ piece
50 Ohm
terminator
Uplin
k
Nor
mal
Uplin
k
Nor
mal
Uplin
k
Nor
mal
AUI
AUI
AUI
AUI
3C16700.book  Page 13  Tuesday, July 13, 1999  9:59 AM