Installing the 3Com Impact Digital Modem 2-5
3Insert 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.
4Connect 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.
5Connect 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.
6Plug the transformer end of the power cable into a
standard 117V ac wall outlet.
7Connect 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.
8Connect 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.