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User Manual
Setting up your telephone
Connection and conditions for use
You can connect your SD8421 to a direct exchange line (DEL), a line connected to a local exchange, with its own phone number; to an extension socket connected to a DEL; or to an extension on an approved compatible PBX. Do not connect the SD8421 as an extension to a payphone.
How many phones can you connect?
The ringer equivalence numbers (RENs) of all instruments (phones, fax machines, etc.) connected to an exchange line must not add up to more than 4, otherwise, one or more of them may not ring and/or answer calls correctly. The SD8421 has a REN of 1, and most other telephones have a REN of 1unless marked otherwise.
Radio signals between handset and base unit
To use your handset and base unit together, you must be able to establish a radio link between them. Be aware that:
•Sitting the base unit as high as possible will give better results, in a
•Any large metal object, like a fridge, a mirror or a filing cabinet, between the handset and base unit may block the radio signal.
•Other solid structures, like walls, may reduce the signal strength.
Choosing a site for the base unit
The base unit should be placed on a level surface, in a position where:
•The mains adapter plug will reach a 230 V AC switched mains supply socket; never try to lengthen the mains power cable.
•The telephone cable will reach your telephone line socket or extension socket.
•It is not close to another telephone, this can cause radio interference.
•It is not close to a sink, bath or shower, or anywhere else where it might get wet.
•It is not close to other electrical equipment, fridges, washing machines, microwave ovens, TVs, fluorescent lights, etc.
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