Automatic Position Reporting with Winlink

One of the features of Winlink is the ability to locate position-reporting Winlink Users by accessing the Internet. Before explaining this feature note the following comments: First, it should be understood that this feature is for the benefit of those at home (or for Search and Rescue organizations) to instantly locate the latest reported position of the traveler; Second, the information is available to anyone with access to the Internet and knows the Winlink User's amateur radio call sign; Third,  obviously, the more frequently the traveler files a position report the more up-to-date the information will be.

In this example we will use three different call signs to demonstrate the types of information that can be found on the Internet. Information available will depend on the traveler's location in the world. Different charts, maps and aerial photograph are used for different regions. Positions reported in North America provide the best graphics.

The search for a traveler's location starts on: http://www.winlink.org/aprs/aprs.htm. Clicking on this link will open the window shown below:

Note that this window provides the visitor with three options:

1.    Locate the Winlink User: Enter the amateur radio call sign of the Winlink User in the "Station Call Letters" box. Then click on "Display" A webpage will open up that provides a range of positional and relative information of this Winlink User;

2.    View the 40 most recent Position Reports filed by Winlink Users - worldwide. This list not only gives the coordinates of each of these Winlink Users but also by clicking on their call sign, their positions may be viewed exactly as in the example introduced under "1" above; and

3.    Get an introduction to the Automatic Position Reporting System (APRS) by clicking on "APRS Home Page." It will provide many links - worldwide - that inform the visitor about APRS.

Before trying the above options you might care to follow the examples given below first. By way of example, if you had entered DL8MEH (The call sign of a German circumnavigating couple who, at the time of writing were in the San Blas Islands in the Southern Caribbean) and clicked on "Display" the following window would open:

This window is self explanatory. The critical information is the following:

1.    It gives assurance that DL8MEH, indeed this is a position filed by DL8MEH (or whatever other Winlink User you may have called on;

2.    It shows how long ago and the date and time that the position report was received by APRS;

3.    It shows the latitude and longitude together with a brief caption that was reported  by the Winlink User;

4.    The penultimate paragraph highlights the problem that this website has experienced by no longer having access to the MapBlast     maps. It is suggested and indeed necessary to view the position on MSN by clicking on the link provided; and

5.    Finally, this Window provides the opportunity to view a list of other Position Reports, sent via ANY participating system, that are nearby, in this case, DL8MEH.

In most cases the above window is followed by a very rough map that indicates the Winlink User's position. In the case of DL8MEH this was the following display:

DL8MEH shown somewhere between Panama and Colombia.

Because this map is not very precise it is best to click on the link that will allow the visitor to see the reported position displayed on a MSN Map. MSN maps can be viewed at differing scales and also can be panned to enable the visitor to assess the Winlink User's location in relation to other land and sea masses. Examples of the different scales, starting at the most detailed to a hemispheric view are shown below.

The most close-up view available with MSN 

A more detailed view that corresponds with the rough first map provided 

This map has zoomed-out to show the Caribbean and parts of Central and South America 

Finally, a view of the hemisphere that covers the Americas

Position reporting applies equally to land based Winlink travelers. In the next following example, the Founder of AussieWinlink reports his position at his ski club lodge on the Snowy River, at Guthega Village in the Kosciuszko National Park in Australia's Snowy Mountains. 

Unfortunately, this is the most detailed map that is available for the Snowy Mountains. 

Here is the hemispheric view showing Australia and the Winlink User's position.

Additional features that are available for positions in North America are aerial photographs and topographic maps that give a more detailed view of the traveler's position. A few examples are given below: 

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Back Creek in the center, Severn River to the northwest and Chesapeake Bay at right.

Below a similar topographic and aerial view presentation of the Potomac (to left) and the Anacostia (to right) Rivers and the Washington Channel in the center. The national mall is in the long rectangular area running from east to west with the Lincoln Monument at the far left near the river, the various memorials and Smithsonian Museums on either side of the Mall and the Capitol buildings at the far right. All are in walking distance from the anchorage (and marinas) in Washington Channel (see http://www.aussiewinlink.org/media_release_52.htm.)

A topographic map of Washington Channel and nearby areas available via Winlink

Aerial photo of Washington Channel, with Haines Park at left and marinas and restaurants at right.

There are also a few colored aerial photographs that pop up when viewing the position of Winlink Users in Central America. It shows the position of a Winlink User near Panama City. (The range of aerial photographs available for this area is still to be determined.) 

A Winlink User reporting a position nearby the Panama Canal

Another Winlink User reporting a position at the Kralendijk anchorage in Bonaire
 

Finally, the first APRS window provides the opportunity to get a listing of 40 "Position Reporters", from all sources including Winlink, that are nearest the traveler that you are following. Click on: Click here to find nearby APRS activity. Having such a list is useful if ever it is necessary to seek help from others in contacting the travelers you are interested in. First, of course, one would try doing so via Winlink onboard email; however, if that would fail it is possible to contact nearby position reporters. Those with the red-white-blue icon, and highlighted in bold on the list, are Winlink Users. The list shows the position of all these nearby stations as well as the distance that are were away from your contact. Most importantly the list also shows how old the report are. It is expressed in days, hours, minutes and seconds. Those that are deemed no longer relevant are parsed from the system. Below is an example; it covers all reported positions, in this instance in a radius of nearly 600 nautical miles. It includes 16 Winlink Users. Those knowledgeable about radio amateur call signs might like to check on how many different nationalities are included. A quick look shows: Canada, England, Germany, Netherlands, Panama and USA.

Stations Near DL8MEH (last 240 hours)

The filing of position reports by Winlink Users and is a relatively simple matter. On a submenu of the AirMail software used by Winlink, the Winlink User simply enters a brief notation that is intended for inclusion with the position report. If navigational equipment is interfaced with AirMail than the coordinates will be automatically entered. Alternatively, it would be necessary to read the coordinates of a GPS and manually enter the information. It will be transmitted as dictated by the Winlink User, that is, either once per day, with the next transmission or attached to each and every transmission that is made. Of course with Winlink, Position Reports can be send at any time around the clock. In most cases these Position Reports will almost instantaneously be available on the Internet.

Those interested in pursuing this topic further should follow the links provided at www.findu.com. This includes not only Winlink activities but also interesting work on the topic around the world, including Australia.

Happy hunting.

AussieWinlink
25 September 2004

TO VIEW S/Y ATLANTIS' LATEST REPORTED POSITION REPORT

Click on this link: http://www.aprs.net/cgi-bin/winlink.cgi?DL8MEH

Once that webpage opens up play around with the links provided to:
1. Scroll down to also view an aerial photograph of the vessel's location, where available;
2. View the vessel's position (Zooming IN or OUT) on a much more detailed map/chart offered by MSN; and
3.  Click on "Nearby APRS activity" to count the number of nearby Winlink Users (Those with this icon).

Copyright © 2002-2008 AussieWinlink. Material may be quoted with acknowledgement of its source. Last modified: September 28, 2008