Chapter3 Setting Up the Cisco Unified IP Phone
Understanding the Cisco Unified IP Phone 7970G/7971G-GE Components
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Cisco Unified IP Phone Administration Guide for Cisco Unified CallManager 5.1 (SIP), Cisco Unified IP Phones
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Using External Devices with Your Cisco Unified IP Phone
The following information applies when you use external devices with the
Cisco Unified IP Phone:
Cisco recommends the use of good quality external devices (speakers,
microphones, and headsets) that are shielded (screened) against unwanted radio
frequency (RF) and audio frequency (AF) signals.
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 shielded cables for the external device, or use cables with a better shield
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.
Caution In European Union countries, use only external speakers, microphones, and
headsets that are fully compliant with the EMC Directive [89/336/EC].