RAYNET use of APRS

Cheshire RAYNET group made its first use of APRS for a live event at FROSTBITE '96

FROSTBITE is a two day event in which around 200 runners compete over sections of the "Sandstone Trail" and "Cheshire way" footpaths. RAYNET provide communications for event safety and produce the event results.

This year, in addition to normal voice communication, we used an APRS network, complete with two GPS tracking units, to display real time event data in the control centre. The following link contains pictures showing some of the weekend's activity. FROSTBITE 96 pictures

As well as the description of the event on this page I've included the text of the Cheshire RAYNET press release .This was automatically exported in HTML format from Lotus WordPro

The data network was carefully planned before the event and used a dedicated 70cms frequency. In addition to APRS we also set up a BBS to hold start times and result data. However, the vast majority of activity was using APRS.

The APRS network is best described by reference to this data network diagram (1054 x 750 in GIF format).

The WIDE area digipeater was set up on a local hill on day1 and at a RAYNET member's QTH on day 2. Carefull planning of the digipeater site paid off on the day and there were no problems for any of the outstations in gaining access. The low power GPS trackers were set to digipeat via other stations and were almost always within range of either a checkpoint outstation or the main digipeater.

At the event control centre two APRS systems were set up as Master and Slave. The Master unit ran APRS DR4, this version allows objects to automatically follow a pre-defined course at a given speed. Objects representing the lead and tail runners were placed on the map at speeds of 6 and 2 knots respectively. Minor corrections were made to these positions as the event progressed and reports were received from checkpoints of the first or last runners arriving. The Slave APRS unit (running APRS 7.4e) provided a "read only" system which allowed people to read information from the system without risk of changing anything.

Three mobile stations ran APRS from checkpoints around the course and a fourth, fixed, station was at the finish hut. These stations sent regular APRS bulletins showing information such as how many runners had passed the checkpoint, weather conditions, other resources at the site e.g. First Aid. The current situation at all the checkpoints could be viewed instantly from control using the map display or the bulletin list.

In addition to the above two mobile stations were equiped with GPS tracking systems. One of these was located on a car used to transport drinking water around the course. The other was used on day 2 as a "Manpack Mobile", the system was put into a rucksack and carried by the sweep team who walked the course at the back of the field to located any lost or injured runners. This was particularly effective as the exact position of the sweep team was visible in control whenever required.

If you want to see how the event progressed download these APRS HST files & map . This, version of the Cheshire map this contains the course and checkpoint numbers in purple. Put the HST files in the \APRS\HSTS\ subdirectory, then use the File Replay commands within APRS. To track the GPS units specify either G6GAK-9 or G0PJA-9 as the callsign when prompted.

Here are two screen shots captured during the event (Thanks to G0HQB for providing these)

Many thanks to the following amateurs who put in lots of hard work both before and during the event to make the use of APRS so successful.