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[aprssig] APRS messaging used on Ironman UK event

Chris Moulding chrism at crosscountrywireless.net
Thu Aug 5 09:58:43 UTC 2010

As part of the discussion about messaging over APRS here's a copy of a 
quick report I
wrote on it's use in a major event last weekend:

Last weekend I was a member of the RAYNET team providing amateur radio 
communications safety cover to the Ironman UK extreme triathlon event.

This year the APRS Messenger program was used to provide data links back 
from the
checkpoints to the main Silver control at the event HQ at Rivington.

A lot of the development and upgrades of the program in the last few 
weeks added
features such as the message output to an Excel spreadsheet and APRS-IS only
messaging to support this event.

For the competitors the race started at 6am with a 2.4 mile swim then a 
112 mile
bike ride across some very hilly terrain followed by a 26.2 mile marathon.

For the control operators the event started the day before setting up masts,
antennas and equipment with some last minute APRS training of operators 
by Ross,
G6GVI and Jack, G8HIK.

During the event 386 APRS messages were sent over the 144.800 MHz UK APRS
channel using existing igates and digipeaters and the traffic was 
recorded at
control with a lot of competitor position information and general non urgent
traffic being sent. This freed the voice channels up for the quicker 
of urgent traffic such as calls for the medical team and event marshals. 
It also
significantly reduced the workload on the control operators and allowed
questions on event progress from the event organisers, medical teams and the
police to be answered quickly with a quick search of the Excel spreadsheet.

The message traffic can be viewed on this webpage:

http://aprs.fi/?c=message&call=G6GMR <http://aprs.fi/?c=message&call=G6GMR>

On the event a wide variety of APRS equipment was used with APRS Messenger
including Kenwood rigs, CCW Digi Trackers, OpenTrackers and others. One
checkpoint manually entered the messaging format into UI-View. Another
checkpoint sent messages via an iPhone running the OpenAPRS app. I also 
set up a
30m GMSK-250 igate (G6GMR-63) as two operators wanted to try HF APRS but 
due to
the pressure on operators during the event that was dropped.

The APRS Messenger program worked well under the heavy traffic with only 
a few
bugs; mainly text string parsing on the Excel spreadsheet output. At 
control I
used one PC running APRS Messenger v2.75E as a 2m and 30m local Igate 
data to the APRS-IS and a separate PC running APRS Messenger v2.76 as a 
Igate for the G6GMR messaging. Connection to the APRS-IS was by 3G wireless

As the competitors approached control several thousand spectators 
arrived and
from 12 to 3 pm the 3G connection on the radio Igate PC kept closing due 
to the
amount of traffic saturating the local cell site. At one point I had to 
the 3G connection every two minutes. Later on in the event after the 
left the same 3G connection ran for 7 hours without a problem. A point 
to bear
in mind for future events.

I made a record during the event of some points I could improve in the 
and the latest version (v2.77) has been updated following the event.

I must thank all the RAYNET operators who used the program during the event,
including some who had never used APRS before and the operators of the local
APRS igates and digipeaters who made sure that their stations provided 
during the event. Also a grateful thanks to Ross, G6GVI and Jack, G8HIK 
who ran
the APRS training on Saturday evening allowing me to set up the APRS 
station in
relative peace!


Chris, G4HYG

Chris Moulding
Cross Country Wireless
7 Thirlmere Grove, Bolton, Lancs, BL4 0QB, UK
Tel/fax: +44(0)1204 410626
Mobile:  +44(0)7752 391908
Website: http://www.crosscountrywireless.net

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