To Connect The Modem - HP Compaq Presario,Presario 2105 Reference Manual

Modem and Network Connections

To Connect the Modem

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CAUTION: Your built-in modem may not work with multiple phone
lines or a private branch exchange (PBX). It cannot be connected to a
coin-operated telephone and does not work with party lines. Some of
these connections may result in excess electrical voltage and could
cause a malfunction in the internal modem. Check your telephone line
type before connecting your phone line.
4–2 Reference Guide