Cisco Unified IP Phone 7940G Specification Guide

Depending on the quality of these devices and their proximity to other devices
such as mobile phones or two-way radios, some audio noise may still occur. In
these cases, Cisco recommends that you take one or more of the following actions:

Move the external device away from the source of the RF or AF signals.

Route the external device cables away from the source of the RF or AF
signals.

Use screened cables for the external device, or use cables with a better screen
and connector.

Shorten the length of the external device cable.

Apply ferrites or other such devices on the cables for the external device.

Cisco cannot guarantee the performance of the system because Cisco has no
control over the quality of external devices, cables, and connectors. The system
will perform adequately when suitable devices are attached using good quality
cables and connectors

In European Union countries, use only external speakers, microphones, and
headsets that are fully compliant with the EMC Directive [89/336/EC].

To install the Cisco IP Phone, perform the following steps. See

 for a

graphical overview of these steps.

Connect a Category 3 or 5
straight-through Ethernet cable
from the switch to the 10/100
SW port.

Each Cisco IP Phone ships
with one Ethernet cable in
the box.

See the

 for guidelines.

Connect the handset to the
Handset port.

—

—

Connect a headset to the
Headset port.

Optional. You can add a
headset later if you do not
connect one now.

See the

 for supported

headsets.