On Jul 5, 6:24 pm, GeoffSchultz wrote:

I got the Garmin GPS 17-HVS today and installed it. As it turned out,
I had to use a NMEA input on my G3 course computer as the 6001 control
head doesn't support lat/long NMEA sentences. It worked just fine and
I when I simulated a failure of the RayStar 120 by disconnecting it,
everything kept working as expected without any Postion Fix Lost
errors. I really don't know which data source (SeaTalk or NMEA) was
being used by the C-80 chartplotter, but there were no problems.

-- Geoff

I did some more testing today and found that it didn't quite work the
way that I thought it did based upon yesterday's single test. Most of
the time I get a Fix Lost error on the C80 and then about 10 seconds
later it resumes using the NMEA position data. Some times it failed
over without any errors. The problem with this is that when you're
navigating to a route, it stops navigating and you have to restart and
advance to the correct waypoint.

The other issue that I see is that the RayStar 120 can take a LONG
time to obtain a position fix and the C80 seems to give priority to
the SeaTalk position data over the NMEA data, despite that fact that
the RayStar hasn't obtained a fix yet. The Garmin 17 obtains a fix
within seconds.

I decided to disconnect the RayStar 120 and just have it as a warm
spare that can be connected in a few minutes if the Garmin 17 fails.
Not ideal, but it works much better than old system.

-- Geoff