3Com DIGITAL MODEM User Manual

Contents

Installing the 3Com Impact Digital Modem 2-53 Insert the 9-pin male end of the 3Com Impact digitalmodem-to-Macintosh serial signal cable into theconnector labeled Computer on the digital modem’s backpanel and tighten the connector screws.4 Connect the other end of the 3Com Impact digitalmodem-to-Macintosh serial signal cable to the serialcommunications port on the back of the Macintosh.The serial communications port is the mini-DIN, 8-pin serialport connector, indicated on the Macintosh connector panelby the telephone handset imprint.5 Connect the 3Com Impact digital modem power cable tothe connector marked 12V AC on the back panel of thedigital modem.See Figure 2-1 for the location of the 12V AC connector onthe digital modem’s back panel.6 Plug the transformer end of the power cable into astandard 117V ac wall outlet.7 Connect the RJ-45 (8-pin) connector end of theRJ-45/RJ-11 ISDN cable to the RJ-45 connector labeledWall on the digital modem’s back panel.See Figure 2-1 for the location of the RJ-45 connector on thedigital modem’s back panel.8 Connect the RJ-11 (6-pin) connector end of theRJ-45/RJ-11 ISDN cable to the RJ-11 ISDN wall jack.CAUTION: The 3Com Impact digital modem is designedto operate with Basic Rate ISDN 2B1Q U Interface networkterminations. An internal Network Termination device(NT1) is built into the digital modem. Do not connect the3Com Impact digital modem ISDN port to a standardanalog telephone jack or to an external NT1 device. Makesure that it is connected to the ISDN jack.