US Robotics 005689-03 Manual page 59

Cable Requirements Cable Requirements
The connection from the modem to the computer must be made with a high
quality, shielded cable to ensure compliance with FCC limits.
Connecting to the Telephone Company Connecting to the Telephone Company
It is not necessary to notify the telephone company before installing the modem.
However, the telephone company may request the telephone number(s) to which
the Sportster is connected and the FCC information printed on pages 59–60.
Be sure that the telephone line you are connecting the modem to is a standard
analog line and not a digital (PBX), party, or coin telephone line.
If the modem is malfunctioning, it may affect the telephone lines. In this case,
disconnect the modem until the source of the difficulty is traced.
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