Originally Posted by JayH
I think the land-based antenna claim is bogus. I've seen boats (like Boatman61) cross the Atlantic with a SPOT. Satellite data transmitters are not difficult, uncommon, or expensive. I see no reason to doubt that the SPOT is transmitting to a satellite.
The SPOT uses simplex data, not duplex like phones, so we're talking about different services. The SPOT does not suffer from the same problems that have plagued GlobalStar phones.
The GlobalStar simplex coverage map is here:
Globalstar Coverage Map: Simplex Data and Asset Tracking
No, that is their actual network architeture, go look it up...and even SPOT/Global Star show coverage gaps in Pacific/Atlantic.
SPOT uses the Global Star network, and while that network is better suited for data traffic than voice, it still has some basic architectural limits.
Their advertised coverage has improved daramtically in recent years, but there are still significant lower probability to no coverage areas well offshore
. Also in my experience, with both SPOT and Global Star phones, there are areas of poor coverage within their advertised coverage areas. For example, Ive had many SPOT messages dropped in Central America
(as did the daughter of a cruiser who was murdered in N Honduras
a few years back).