The Iridium network and APRS

A change in my work role means that I will be travelling our to remote communities regularly.  As a safety precaution the company require me to have some form of satellite communication. There were a couple of options that I was looking at, one being the Spot range and the other, the Garmin range.  I was aware that there was a way of getting the Spot beacons onto the APRS network, and so initially I was leaning towards the Sport X.  However I have owned a number of Garmin devices over the years and always found them to be well made.  

So, after much research I decided on a Garmin inReach Mini  2.  This devices used the Iridium satellite network.  The device itself is small yet can do so much. It will beacon its position at regular internals (10, 20 &30 min) and it also allows for unlimited 'check-in' messages and also two way text messaging.  It can be used stand alone, but is much easier to used when paired to a smart-phone via Bluetooth.

The inReach Mini 2 beside my ID-51A

 

It turns out that the guy who wrote the code for getting Spot beacons onto APRS has also written code for the Garmin inReach.  Enter Mark VK5QI.

Mark is a very active Amateur Radio enthusiast.  (And I suspect active in lots of other areas as well.) His website can be found HERE, this is more for getting an idea of the kind of things he get up too, but don't expect regular post. The last post is a couple of year old! However, he has written huge amounts of code, and this is where our paths have again crossed.  I say again because Mark helped me out years ago when I was registering my D-Star radio, and then again when I was playing around with tracking Weather Balloons. Anyway, it turns out that he is the author of some code called inreach2aprs (and also for that matter, spot2aprs).  The code can be found HERE.  

This code sends a queries (or request) to the Garmin website and received the position data, which it then processes and converts into an acceptable format for the APRS network.  Easy!

A simple bash script (sat2aprs.sh) is called via crontab at predefined intervals (in my case every 20 minutes).

sat2aprs.sh

#bin/bash

 

CALLSIGN=[callsign]

SSID=-[APRS SSID]

PASSCODE=[APRS Passcode]

MAPSHARE=https://share.garmin.com/Feed/Share/[add unique URL extension]

PASSWORD=[mapshare password, if used]

 

cd /home/pi/inreach2aprs/

 

python inreach2aprs.py --mapshare_url=$MAPSHARE --mapshare_password=$PASSWORD  --comment="Via Iridium & inReach2aprs" $CALLSIGN $SSID $PASSCODE

 

 

The line in crontab looks like this:-

*/20 * * * * /home/pi/sat2aprs.sh >/dev/null 2>&1

If you want to change the APRS symbol this need to in modified the inreach2aprs.py program itself.

Thanks to Mark VK5QI for his assistance is getting me up and running.