3Com 3C16792 User Guide - Page 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) AUI UNpolrimnkal AUI AUI UNpolrimnkal AUI UNpolrimnkal 'Y' piece 50 Ohm terminator 13