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Manlio Manlio is offline
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First recorded activity by BoatBanter: Jan 2007
Posts: 23
Default NMEA and SeaTalk on same network

Followup to msg on Sun, 02 Mar 2008 18:08:06 +0000, Larry
:
(Original msg on bottom)

Thanks to all of you. You have just confirmed all my presumed doubts
making them certainty.
BTW it's too much important to have a "spare" GPS ( I will keep it off
in the right way) as, despite my age (!!) I will have some trouble to
unbury my old sextant !! :-))

Manlio



Manlio wrote in news:kgoks3lt7mrm6s0cavklpprrs2t1sf2kro@
4ax.com:

I would like to add a second GPS (Raystar 125) connecting its SeaTalk
output signal to the SeaTalk network. This would be meant to be a
reserve in case of failure of the first one. May I leave it in
operation, having GPS data coming from two devices, or it's better to
keep it off and disconnected while the first one is in operation ?



You must NEVER have TWO GPS units talking to the network at the same time.
They will NEVER put out the same data. The results are that every plotter
on the boat goes crazy with the conflicting data streams, your position
jumping from A to B to A to B all the time.

If you want to have a backup GPS, that's fine as long as only ONE of them
are talking to the system at a time. We have two, one Raystar 120 and one
Garmin. There is a simple toggle switch to select which one of them is the
talker so noone can set both of them talking simultaneously.