Facts About Cellular Data Transmission - Nokia 9000 User Manual

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types will invalidate any approval or warranty
applying to the apparatus, and may be dan-
gerous.

Facts about cellular data transmission

The Nokia 9000 Communicator employs the dig-
ital data transmission capabilities of the digital
cellular network to send faxes, short messages,
mail and to establish connections with remote
computers.
Cellular data connections can be made from
most locations where your cellular phone oper-
ates. However, it is recommended that you move
the communicator to a location where the
strongest possible cellular signal can be ob-
tained. When the signal is strong, data transmis-
sion is efficient. In general, you should not
expect the same performance from cellular data
communications as from landline communica-
tions due to the inherent characteristics of the
cellular environment.
The following factors may impair cellular con-
nections:
Noise
Radio interference from electronic appliances
and equipment, as well as from other cellular
phones in metropolitan areas where cellular
telephones are prevalent.
Handover
As the cellular phone user moves from one
network cell to another, the signal strength of
the channel drops and the cellular telephone
exchange may hand the user over to a differ-
ent cell and frequency, where the signal is
stronger. A cell handover may also occur
when the user is stationary due to varying
cellular traffic loads. Such handovers may
cause slight delays.
Electrostatic discharge (ESD)
A discharge of static electricity from a finger
or a conductor may cause erroneous func-
tions in electric devices. The discharge can re-
sult in "garbled" display and unstable
Facts about cellular data transmission
When you disconnect the power cord of any
accessory, grasp and pull the plug, not the
cord.
software operation. Cellular connections may
become unreliable, data may be corrupted,
and the transmission halted. In this case you
need to end the existing call (if any), switch
off the phone interface (if on) and remove the
battery. Then replace the battery and estab-
lish a new cellular connection.
Dead spots and dropouts
Dead spots are areas where radio signals can-
not be received. Dropouts occur when the cel-
lular phone user passes through an area
where the radio signal is blocked or reduced
by geographic or structural obstructions.
Signal impairment
Distance and obstacles can cause out-of-
phase reflected signals that result in a loss of
signal strength.
Low signal strength
Due to either distance or obstacles, the radio
signal strength from a cell site may not be
strong enough or stable enough to provide a
reliable cellular connection for communica-
tion. Therefore, to ensure the best possible
communication, remember to consider the
following points:
• The data connection works best when the
communicator is in a stationary position.
Attempting cellular communication while in
a moving vehicle is not recommended. Fax
transmission is more easily impaired than
data or short message transmission.
• Do not place the communicator on a metal
surface.
• Check that the cellular signal strength on the
communicator displays is sufficient (see
chapter 2 "Getting started: Indicators - Using
the applications" and chapter 14 "Phone
interface: Display indicators" of this manual).