HP Brio 8500 User Manual page 5

Important Safety Information
Never touch or remove the communications card without first removing the
connection to the telephone network.
Analog Telephone Line
To use the HP communication card, you must have an analog telephone line. If
you are not sure if you have an analog telephone line or digital line, have it
verified by the person in charge of your telephone system before you install the
modem.
Caution The modem will be damaged if you use a digital telephone line.
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