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Sending digital messages over amateur radio is
a measure of last resource. Obviously, Users with direct access to the
Internet or commercial communication facilities, at an affordable cost,
would use these in preference. For example, a complicated graphic will go
ever the Internet in seconds. A communication satellite might move a digital
message at a maximum baud rate (bits per second) of 2400. The best available
protocol available, Pactor - supported by Winlink has speeds that under
optimal conditions range from 200 for Pactor I, 800 for Pactor II and in
excess of 3200 for Pactor III. Actually, Pactor I because of its slow speed
is being phased out by Winlink.
However, there are large numbers of people who, because they are in very remote locations, do not have access to these normal communication facilities. Also, there are people at home who like or need to stay in touch with the distant traveler and have no other means for doing so than via the Winlink network. Furthermore, there can be extreme circumstances, for example, during natural disasters or other national or international emergencies where the normal public communication facilities are completely or partially knocked out. This happened in the US during the 9/11 attacks on the World Trade Center and the Pentagon; during the recent hurricanes in the Caribbean and Baja California, and the current tsunami disaster in South and Southeast Asia. During such catastrophes the amateur radio community comes into its own and, without hesitation, provides communication support to local and official agencies. Unfortunately, virtually all of this support is in the form of voice communications, that is, the spoken word. However, the greater need often is for the bulk transmission of digital data, like lists of missing persons or vessels; requirements for medicine and equipment, and mobilization of resources. A recent example is the Winlink list of cruising boats tracked during the tsunami aftermath. It can be viewed at: www.bur.st/~philsuth/tsunami_status. Finally, it is important to understand that digital communications provide a permanent record, printed or in electronic format, that can without additional effort be faultlessly distributed to all who need the information.
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