Actually the SPOT units do require a clear view of the southern sky, especially the further north latitude you are located, as they use Globalstar's sat network to transmit the messages. Globalstar sats are closer to the equator, and earth's curvature begins to block them out particularly when you have higher terrain near to your south. The SPOT receives its GPS coordinates from the regular GPS sat system, but to transmit that location, they need to see south to the Gstar satellites. Could be a bad unit with the tendency to shut itself off - I would say close to 1/2 the time. Just not impressed with the unit, the damn buttons are small also, and my big fingers can hardly push and hold the on and ok buttons at the same time to get the tracking going. I guess as a former Globalstar sat phone user, I shouldn't have expected much more. Anyone had to send a unit in for warranty? wonder what the turnaround time is, and if they will credit the downtime to your subscription. I went through all this crap before with Globalstar phones, and really am not looking forward to trying to get any kind of customer service. I think I should have gone with Spider Tracks right away, as that is probably what I will end up with in the end.