Losing GPS - Problem solved

Seven Spades

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About three years ago we updated all the navigation equipment on the boat to the latest Raymarin Axiom system, we replaced almost every part of the system except the GPS reliever. As a result when we switched the system on it would take a few minutes to acquire the satellites.

At the start of last season we launched the boat and I noticed that the date was wrong, i went through all the settings and I could not work out what was wrong. Eventually I called Raymarine and they told me that the old GPS receiver had the equivalent of the Y2K but and had run out of registers and so the clock had reset to 2001 or something, So I was advided to disconnect it and use the GPS built into the Axiom on the Binnacle. This solved the date issue but on occasion it wodl take 10-20 minutes to acquire satellites. Then from time to time our AIS alarm would go off on passage and we wooudl lose the route we were following. I woud then have to follow a route and then advance waypoints to get everthing back together.

It turns out that the AIS alarm goes off and the system stops following a route if satalites are lost even for a fraction of a second. Clearly the GPS reciever inthe Axiom is very weak. So I took the plungs and bought a RS150 SaeTalkNG reciever and fitted it this weekend. What a difference, when I switch the system on the GPS acquires satalites before Lighthouse 4 has booted up consequently as soon as the plotters come alive I have GPS. I could not be happier. The only thing I am not really happy about is the cost, on top of the GPS I had to buy a SeaTalkNG expansion bar, two cables and two blanking off pins which cost another £80 on to of the cost of the GPS.

I wish I had fitted a new GPS reciever three years ago this new one is so good. I am posting this be3cause I suspect that many people are probably using the built in GPS in their plotters unaware of the improvement achieved by a dedicated receiver.
 
You didn't have to remove the old GPS, you can go into lighthouse menu and select which GPS the plotter uses for data. If you didn't do this how do you know the plotter has ever been using the inbuilt Axiom GPS?
 
I have both an Axiom at the helm and an old but still working Seatalk GPS (not NG) with ST60 display. The Axiom internal GPS consistently gets a fix before the system has fully booted as on first chart display there is a fix. Even the very old Raystar GPS still gets a fix within 5-10 seconds - it used to be minutes plus occasional loss of position until I changed the button battery in it.

I also have a third and fourth GPS, one built into the VHF receiver and the other in a small independent chart plotter at the chart table. Both these get fixes within seconds. Technically there is also a 5th GPS as there is a separate one for an Emtrak AIS tx/rx but there is no display of this.

I say this because unless your Axiom is mounted somewhere with an obstructed "view" of satellites (ie down below in a steel or alloy yacht) I would say it is faulty if it is losing fix regularly.

And it is somewhat more profitable for Raymarine to sell a new StNG GPS than to repair the Axiom or tell you to change the button battery in an old Seatalk GPS mushroom. I have had very mixed experience with Raymarine service - one time really excellent, at other times very poor, and inclined to tell you just to buy new instead of repairing something eminently repairable. Once by me, once by the electronics repair people in Poole.
 
You didn't have to remove the old GPS, you can go into lighthouse menu and select which GPS the plotter uses for data. If you didn't do this how do you know the plotter has ever been using the inbuilt Axiom GPS?
Actually that is not correct. The old GPS was hard wired and for some reason you could not select a different data source for GPS. It was the RAYMARINE support agent who diagnosed this and told me what to do. It makes no difference in any event the old GPS feed the wrong date into the system so all the tides were wrong so it had to go.

the disappointment was the poor reception by the built in GPS of the Axiom.
 
I have both an Axiom at the helm and an old but still working Seatalk GPS (not NG) with ST60 display. The Axiom internal GPS consistently gets a fix before the system has fully booted as on first chart display there is a fix. Even the very old Raystar GPS still gets a fix within 5-10 seconds - it used to be minutes plus occasional loss of position until I changed the button battery in it.

I also have a third and fourth GPS, one built into the VHF receiver and the other in a small independent chart plotter at the chart table. Both these get fixes within seconds. Technically there is also a 5th GPS as there is a separate one for an Emtrak AIS tx/rx but there is no display of this.

I say this because unless your Axiom is mounted somewhere with an obstructed "view" of satellites (ie down below in a steel or alloy yacht) I would say it is faulty if it is losing fix regularly.

And it is somewhat more profitable for Raymarine to sell a new StNG GPS than to repair the Axiom or tell you to change the button battery in an old Seatalk GPS mushroom. I have had very mixed experience with Raymarine service - one time really excellent, at other times very poor, and inclined to tell you just to buy new instead of repairing something eminently repairable. Once by me, once by the electronics repair people in Poole.
This is very interesting, the Axiom is fitted in the cockpit is completely open. I don’t know if it is faulty when I spoke to Raymarine they were very dismissive of the built in GPS and said that they are not very resilient and so even the proximity of the compass might obscure the satellite signals. I have no idea if this is true, most of the time when we first switched on the system it would take about 5 minutes to acquire satellites. Once acquired is was usually. not a problem, but on longer journeys like a channel crossing I might have to re-start the course a couple of times or not at all, it was all very random.

i have a Digital Yacht AIS with its own GPS mushroom but it does not show up as a data source in Axiom so whilst it is a source of GPS the plotter could not use it.

i thought that there might be other people with Axioms and not using a separate GPS who might benefit from my experience. I think that the outcome is great. RAYMARINE knew all about the problems with my old GPS and I was told it could not be updated only replaced or removed.
 
i have a Digital Yacht AIS with its own GPS mushroom but it does not show up as a data source in Axiom so whilst it is a source of GPS the plotter could not use it.

i thought that there might be other people with Axioms and not using a separate GPS who might benefit from my experience. I think that the outcome is great. RAYMARINE knew all about the problems with my old GPS and I was told it could not be updated only replaced or removed.
To use the Digital yacht GPS you would need to connect the AIS NMEA out to the Seatalk network. If your model of AIS has an NMEA 2000 connection you could use that, with a Devicenet to STNG converter cable, cost about £25.

Despite what Raymarine may have left you thinking, the GPS in the Axioms work perfectly OK, i have fitted many of them and never had an issue, even when fitted below decks. I suspect yours is faulty and they fobbed you off, rather than replacing the unit.
 
I take it that you have never, ever, bought anything new for your boat ?
Somehow my remark has been misunderstood. The OP had suggested that he had to spending cash to sort the issue & I was really offering concealed sympathy. How often does one end up spending more than one intended just to get things to talk together. It is one reason that most of my gear is isolated & not daisy chained. Very nice when it works of course —-But 😒😒😒
 
The built in GPS in the Axiom is very poor. Ours takes at least 5 minutes to get a fix and often loses the fix for no reason. It makes you think that if a cheap GPS receiver in a phone gets a fix quicker and is at least as accurate then Raymarine must be doing something wrong. The only thing different I would have done is bought an NMEA 2000 GPS antenna that wasn't a Raymarine one and saved a few quid 🤔.
 
I posted this for people like you as I felt that my experience was probably not unique. The Raymarine was a shoe-in as I had a seatalkNG cable in the headlining so it took seconds to connect it with the cables.
 
The built in GPS in the Axiom is very poor. Ours takes at least 5 minutes to get a fix and often loses the fix for no reason. It makes you think that if a cheap GPS receiver in a phone gets a fix quicker and is at least as accurate then Raymarine must be doing something wrong. The only thing different I would have done is bought an NMEA 2000 GPS antenna that wasn't a Raymarine one and saved a few quid 🤔.
Having a B&G chartplotter myself, I'm very surprised to read this. I must apologise to @Seven Spades as I must admit my first assumption was that they must've been doing something wrong.
 
I had an old Raymarine chartplotter on my boat and a Raymarine AIS500 unit. I did not have any problems getting a fix with this setup.

Once I replaced the old chartplotter with a Axiom+ 9", I've had a strange recurring problem. It can take up to 30 minutes to get a fix. Once I get a fix, it generally is maintained, but not always. Every time I turn on the electronics, I have some variable amount of time before I get a fix. It could be 5 minutes or up to 30 minutes.

I also have "AIS loss" signals happening at the same time. These also go away eventually. During the time the GPS won't fix, I am not doing anything electrical on the boat. I'm not using the VHF (though it is on) and I'm not putting any electrical loads on the system. I'm plugged into shore power.

I've tried all variations of Axiom GPS settings to see if it makes any difference and it doesn't. I've removed my chartplotter from the binnacle to see if it is some weird interference, but it doesn't make any change. I've set up the Axiom to only use the internal GPS, so I'm confused by why I'm having this problem. There is some conflict, but why is it only on startup? Once the fix becomes stable (it remains for more than 15minutes), then it will do that for the rest of the day (in general, but it has dropped at inopportune times).

It seems the Axiom+ is at fault given that the old chartplotter worked fine with the AIS500. Or, there is some glitch between the Seatalk network (where the AIS500 lives) and the NG network where the Axiom lives. The fact that it does work mostly reliably after a period of time is very confusing to me.
 
I posted this for people like you as I felt that my experience was probably not unique. The Raymarine was a shoe-in as I had a seatalkNG cable in the headlining so it took seconds to connect it with the cables.
Seven Spades,
I had exactly the same issue with Axiom. I sent mine back to Raymarine but they gave it a clean bill of health. Still it took a long time to get a fix and would lose it in heavy rain and poor visibility - not exactly what I expected. Like you I bought an external RS150 GPS and the system now gets its fix by the time it has booted up and has not lost it in 3 years of use.
I couldn’t get Raymarine to accept the poor performance, so closed the issue and went sailing!! C’est la vie.
It is a good bit of kit now.
 
My Axiom+ 12 only uses internal GPS and gets location instantly, networked to ST60, ACU400 and Emtrak AIS. Very satisfied with it. It is located outside on the cockpit shelf, below the sprayhood.
 
I have filed a customer support issue with Raymarine/FLIR, I wonder what they will say. Unfortunately, the warranty is over. Going the Raystar 150 route is not cheap.
 
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