AIS Tracking – MarineTraffic
Our on board AIS unit transmits our current position using VHF radio, if we are within about 30 miles of a shore station, dotted round the world’s coasts.
Once further offshore, it is not so easy to be picked up, unless we are near a large commercial vessel which may relay our position.
Sometimes, there are blank spots where there are no shore stations. It doesn’t mean we have sunk, just that our signal is not being picked up.
There are a couple of sites that display the data online – MarineTraffic and VesselFinder are two. Interestingly, they use different shore stations, so if we are missing on one, we might be seen on the other.
Satellite Tracking – Delorme
Our handheld Delorme device on board sends a position point every 30 minutes.
This is picked up by satellite and recorded on Garmin’s Delorme web-site map, more or less immediately, and kept forever.