Originally Posted by
georgetg
You can't just count on the built in Sat DB in your GPS unit for RAIM because some sats may be out for mx...
The RAIM prediction site is much better and yes there are days when half of the US is red/yellow
Cheers
George
This is important. The RAIM prediction in the GPS unit only considers the orbits of the satellites and where they will be at the desired time. It has no way of knowing if they will actually be working when they get there (or were shot down by china).