Originally Posted by IO540
It doesn't [get lost] - the issue is with getting the initial constellation data, and ensuring good satellite reception afterwards.
It seems like a fair approximation of getting lost, when you switch it on at the location it last knew it was at, but cannot find any satellites, after half an hour of trying. That was what happened with my 296, and probably with ACARS' 496.
Incidentally, one of the enhancements in the 5.20
firmware upgrade for the 296 is
"Improved GPS satellite acquisition under certain conditions"!