3Com DIGITAL MODEM User Manual page 22

3 Insert the 9-pin male end of the 3Com Impact digital
modem-to-Macintosh serial signal cable into the
connector labeled Computer on the digital modem's back
panel and tighten the connector screws.
4 Connect the other end of the 3Com Impact digital
modem-to-Macintosh serial signal cable to the serial
communications port on the back of the Macintosh.
The serial communications port is the mini-DIN, 8-pin serial
port connector, indicated on the Macintosh connector panel
by the telephone handset imprint.
5 Connect the 3Com Impact digital modem power cable to
the connector marked 12V AC on the back panel of the
digital modem.
See Figure 2-1 for the location of the 12V AC connector on
the digital modem's back panel.
6 Plug the transformer end of the power cable into a
standard 117V ac wall outlet.
7 Connect the RJ-45 (8-pin) connector end of the
RJ-45/RJ-11 ISDN cable to the RJ-45 connector labeled
Wall on the digital modem's back panel.
See Figure 2-1 for the location of the RJ-45 connector on the
digital modem's back panel.
8 Connect the RJ-11 (6-pin) connector end of the
RJ-45/RJ-11 ISDN cable to the RJ-11 ISDN wall jack.
CAUTION: The 3Com Impact digital modem is designed
to operate with Basic Rate ISDN 2B1Q U Interface network
terminations. An internal Network Termination device
(NT1) is built into the digital modem. Do not connect the
3Com Impact digital modem ISDN port to a standard
analog telephone jack or to an external NT1 device. Make
sure that it is connected to the ISDN jack.
Installing the 3Com Impact Digital Modem 2-5