GPS Network Problems

[Dockhead]

This is turning out to be a big year of gear failures for me My boat is 11 years old and has been in use for about 9 of those; I guess it must just be that a lot of items of gear are reaching their sell-by dates.

The latest problem -- just when I'm in the middle of solving others -- is that my Raymarined network is losing GPS data intermittently. I have a Raystar 125 mounted to the pushpit. This feeds GPS data to an older Raymarine network consisting of RL80CRC+ at the nav table, RL70RC+ at the helm, and the other usual gear.

I recently connected the NMEA output from the RL80CRC+ to my Icom M604 VHF in order to have position and time data for the DSC functions. This has been working fine for the last couple of months so I doubt any connection to the problem.

Now occasionally the system will lose GPS data and sound and alarm: "Lost Fix". This tends to occur on startup of the system and tends to go away after half an hour or so.

Does this sound like a bad connection? Or do the Raystar GPS receivers fail in this manner? Should I replace it? Then what with -- if I want the new receiver to be compatible with a new network (which will presumably be NMEA2000)?

I guess the main thing I need to know is whether or not there is a failure mode of these GPS receivers which is not a simple dead failure like most electronc gear, or whether this kind of behavior can be a bad GPS receiver. If they never fail like that, then I guess I need to be looking for a bad connection or worse -- some kind of other failure in the network.

As always I will be very grateful for pearls of wisdom from those more knowledgeable and/or more experienced than I.

[goboatingnow]

I presume the raystar is connected via seatalk. If so check all the seatalk connections. My experience is they fail over time.( especially the friction held connectors) Any that can be cutout and hardwired do so.

Dave

[Dockhead]

Originally Posted by goboatingnow

I presume the raystar is connected via seatalk. If so check all the seatalk connections. My experience is they fail over time.( especially the friction held connectors) Any that can be cutout and hardwired do so.

Dave

Thanks! You mean the Seatalk connectors fail over time, right? Or the GPS receivers?

Can I reconnect by NMEA0183? Does that make any sense?

[goboatingnow]

Yes the seatalk connectors give trouble. Inspect them all , depending on cable runs there can be connectors mid run, they get loose, suffer corrosion build or just generally act up.

You could switch to nmea 0183. But I think you have to change the raystar as the seatalk and nmea ones are different parts. ( I'd memory serves me right)

[SoonerSailor]

I experienced this same problem. I ended up replacing the Raystar GPS with a Garmin GPS17x with NMEA output.

BUT - later I ran across some information that there is a little lithium cell inside the Raystar GPS that maintains its memory, and that after some period of time it finally fails, causing above mentioned problems, and needs to be replaced. You might look into this possibility.

Chip

[goboatingnow]

Yes there is a lithium battery it's not normally user replaceable it's used to power memory to keep parameters stored. If it fails generally startup takes along time. But once it has got a fix it doesn't need the battery.

What's the LED on top showing is it green all the time indicating the device has a fix.

The other thing is of you have any other seatalk units connected. There could be a fault there. Disconnect any other seatalk devices to be sure and test.

Dave

[Beausoleil]

The Raystar 125 supports both NMEA or SeaTalk, depending on how it's wired. So if you do decide to change over to NMEA mode, you can do so without replacing equipment. However, if you have any other NMEA equipment attached to your RL80, you may need to install an NMEA multiplexer.

For all it's proprietary faults, SeaTalk is simple to wire - you just daisy chain it.