Guide to Electrical Converters & Adapters
[Special to the Travelite.FAQ]
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When using any kind of modem overseas there are four issues to consider
(in addition to the dual voltage issue of external modems as above): the
connection between the modem and the telephone line, the potential existence
of a digital telephone system, line noise that could interfere with the
modem's signals and a dial tone that may not be recognized by the modem.
The physical connection between the modem and the telephone line is the
easiest problem to solve. However, it is not as easy as just plugging
the telephone jack from your modem into the telephone jack in the wall.
While the most common telephone jack is the North American RJ11, there
are 40 other kinds of outlets and if you are travelling to Europe, Asia
or South America, you will need a telephone jack adapter to make the connection
between the RJ11 jack on the end of your modem's telephone line and the
telephone jack of the country you will be in.
Keep in mind that some foreign-owned hotels utilize the telephone systems
of their home countries, not of their host countries. This is particularly
common in large U.S., British and German hotels. You should check with
your travel agent before you go.
Modems communicate using analog or sound signals while most new telephone
systems use digital signal processing. Digital systems are unable to process
analog signals making it impossible for modems to communicate. Unfortunately,
many large hotels, offices and universities have digital phone systems.
These are characterized by telephones with a digital display or extra
buttons for laundry and video stations. There may also be an outlet for
a data port on the body of the telephone. Plugging a modem into a digital
telephone jack is not recommended as it could connect you to room service
or activate a fire alarm. However, there may be an outlet for a data port
on the body of the telephone.
If you find that your hotel has a digital system without the data port
on the telephone, there are two options: you can use an acoustic coupler
to physically attach the handset to the modem or you can use a digital
interface that plugs into the telephone via the handset jack. You should
ask your travel agent whether or not the hotel you are staying in has
a digital system with data ports on the telephones and the configuration
of these ports.
If there is no telephone jack (that is when the telephone wire comes
directly from the wall and cannot be unplugged) you will need to hardwire
a connection using alligator clips. DO NOT hardwire a direct connection
in a digital system. This could permanently damage your modem and even
shut down the hotel's telephone system. Hardwiring a connection from the
wall in an analog system is more reliable. You should use a line tester
to make sure that a connection has been established before using your
Line noise is a problem that can occur in less modernized countries.
In most cases, you are at the mercy of the telephone exchange but there
are a few tricks that might help reduce the interference. First, try connecting
at lower modem speeds. If you usually work at 14,400 bds., try reducing
to 9600 bds. or even 2400 bds. Or, you can try working very late at night
when there are fewer people using the network.
There is also a type of deliberately created line noise called tax impulsing.
These are high frequency/high pulse signals that are sometimes filtered
out by the hotel PABX. If you are travelling to Germany or Austria, for
instance, these noises will not be filtered out and you will need to take
a line filter in order to use your modem.
If the dial tone in the country you are visiting is not recognized by
your modem, you will probably need to adjust the communication program
that your modem uses. Consult your modem manual for these instructions.
A duplex telephone jack adapter allows the hotel (or office) telephone
and the modem to be plugged in at the same time. This is important because
it might be necessary to dial manually and activate the modem once a connection
has been made. This may be important when making a connection through
a hotel's switchboard.
The advantage of a duplex adapter is that travellers to North America
from overseas will be able to use these adapters to plug their modems
into our RJ11 telephone jacks. They must first unplug the cord from the
telephone in the room and plug it into the RJ11 socket of the telephone
jack adapter with the configuration from their home country. The travellers'
telephone cord that is attached to their modem is then plugged into the
second socket in the duplex telephone adapter. In this way, travellers
who are unprepared for our RJ11 system need not have purchased a telephone
jack adapter in their home country.
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