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Macintosh Modems 25
configurations, some users will not be able to take full advantage of V.90
technology at this time. In order to achieve a V.90 connection, the
following must occur:
1 The server you're dialing in to must support and provide a digital V.90
signal. Your ISP can provide you with a list of dial-up connections and
information on what those connections currently support.
2 The telephone line between your ISP and your modem must be capable
of supporting a 56K connection and contain only one analog-to-digital
conversion. The 56K signal from your ISP begins as a digital signal.
Somewhere between the ISP and your modem, there will be an
analog-to-digital signal conversion so that your modem can receive the
data. There must be no more than one analog-to-digital signal conversion
in the path from your ISP to your modem. If more than one
analog-to-digital conversion occurs, your connect speeds will default to
V.34 (33.6). There may also be impairments on the local lines between
your ISP and your modem. These impairments can prevent or limit V.90
connection speeds. All telephone calls are routed differently, so you
should try making your 56K connection several times. One way to test
this is to dial into a long distance location. Long distance lines are often
much clearer than local lines. It is important to note that telephone
companies are constantly upgrading their systems. Lines that do not
support 56K today may support 56K in the near future.
3 Your modem must be connecting to a V.90/56K server. A pair of 56K
modems will not connect to each other at V.90/56K speeds.
Macintosh Modems
Basic Troubleshooting
Steps
1. Is your modem turned on? When your modem is properly connected
to power and is turned on, the TR and CS lights on the front panel will be
on.
2. Is your power supply connected properly to both your modem and an
electrical outlet? You must use the power supply that came with your
modem; other similar-looking power supplies may be of different
voltages and could damage your modem. When your modem is properly
connected to power and is turned on, the TR and CS lights on the front