RAIM errors and the Apollo GPS

Lee,
What version of system software do you have?
Version 3.5 is the latest, and was issued to correct an overly cautious
RAIM prediction model in the earlier versions.

Since getting mine updated (a year or more ago) I rarely get a RAIM warning.

Rich


Lee Elson wrote:
We've been getting RAIM errors in Southern and Central California with
our GX60 in the past couple of months. The unit recovers in a minute
or so and there doesn't seem to be a pattern (e.g. in a turn, special
altitudes) to the failures. Yes, I know about the earlier discussions
of RAIM error and the GX** but it seems like the frequency is
increasing dramatically. I also note that there are more NOTAMS for
GPS "outages" that sometimes reach our area, 'tho they don't seem to
correlate well with the errors I get. I assume its the military trying
to learn how to jam GPS.

My specific questions:

1) Does anybody else see more RAIM errors than, e.g. a year ago? What
manufacturer/times/places?

2) Do the military interruptions (or whatever is the source of the
NOTAMS) usually last a few minutes?


Lee Elson