Navico RT650 radio and NMEA

[Mikedefieslife]

Think I've seen somewhere that a few people on here have this radio.

I'm curious how you've got it hooked up to the rest of your system.

The radio outputs AIS at 422 and 38.4k baud. Yet it will only receive GPS information at 4800 baud.

On my chartplotter, and I presume many others you can only set a single baud rate, and that is used for both Tx and Rx signals.

Am I right in thinking that without an external multiplexer I have a choice of either having AIS (displayed on my chartplotter from the radio) or GPS (sent from the chartplotter to the radio)?

Bit of a crappy state of affairs.

On a separate note. I must have past 14 container and cruise ships last night. One as close as 50 metres (scary as ****) while I was under sail. Not a single one of them was on AIS.

 

[pvb]

The radio outputs AIS at 422 and 38.4k baud. Yet it will only receive GPS information at 4800 baud.

On my chartplotter, and I presume many others you can only set a single baud rate, and that is used for both Tx and Rx signals.

Am I right in thinking that without an external multiplexer I have a choice of either having AIS (displayed on my chartplotter from the radio) or GPS (sent from the chartplotter to the radio)?

Many people find that fitting a separate GPS receiver to feed the radio is the simplest and cheapest solution. The Evermore SA-320 is often suggested.

On a separate note. I must have past 14 container and cruise ships last night. One as close as 50 metres (scary as ****) while I was under sail. Not a single one of them was on AIS.

I find that very hard to believe, it's more likely that your radio isn't receiving properly.

 

[Mikedefieslife]

I ought to upgrade everything to NMEA2000. 0183 just seem antiquated. The thing is go I but a proper AIS transponder, or just upgrade the radio.

On the subject of the ships. It's bizarre. Not a single one, then other times the only ships that up are ones that 20nm away rather than those I can see with my eyes. Oddly as soon I got into the harbour I got an AIS alert from a class A vessel that was moored.

 

[pvb]

On the subject of the ships. It's bizarre. Not a single one, then other times the only ships that up are ones that 20nm away rather than those I can see with my eyes. Oddly as soon I got into the harbour I got an AIS alert from a class A vessel that was moored.

Unless your radio is getting GPS data, I can't see how it can display proper AIS data. For example, it can't give you the "plotter mode" display, as it doesn't know where it is. And it can't give you the distance away of AIS targets.

 

[prv]

Bit of a crappy state of affairs.

It is. Not uncommon though. Comes from the manufacturers not considering the typical whole system their kit will be installed in. Standard Horizon get good marks here, they have a choice of port settings made available for exactly this situation.

I'd second the suggestion of a separate GPS anyway, on the same power circuit as the VHF. It's good to have the radio able to work even if the plotter is switched off for some reason.

N2k is certainly convenient for yachts, but worth noting that it's pretty much unknown in commercial shipping. NMEA0183 is still the standard there. I was looking at a new model of steerable sat-dome the other day (the kind of thing you see on top of cruise ships to provide Internet connection) and it needs a position and heading input to help it aim at the satellite. The only input it accepted was NMEA0183 at 4800kbps over RS422.

Pete

 

[superheat6k]

I think the Navico RT650 is the same set as the Furuno Radio Ocean RO4800. This had differing baud rates for AIS TX and GPS RX. It wouldn't work properly with a single port GPS such as the Lowrance I bought to go with it, so this was changed to a Garmin GPSMap750 with two ports and that worked just fine.

Because the AIS on the VHF set is only a receiver, and not a transponder, there is no requirement for it to have a GPS built in, it is simply passing on the GPS positional details received from the AIS transponder equipped vessels it shows. Transponders are required by the AIS standards to have their own GPS to provide the reference for their position.

The RO4800 manual is available here if you need a pdf version ...

https://www.dropbox.com/s/kqgu2zdhxhs92rj/Furuno RO4800 Operators Manual.pdf?dl=0

 

[Vladis]

Think I've seen somewhere that a few people on here have this radio.

Am I right in thinking that without an external multiplexer I have a choice of either having AIS (displayed on my chartplotter from the radio) or GPS (sent from the chartplotter to the radio)?

Hi,

This multiplexer does what you need.

Regards, Luis

 

[pvb]

Hi,

This multiplexer does what you need.

Regards, Luis

I'm not sure how that multiplexer could do what the OP asked for. It might also have been more honest of you to have explained that you make and sell this multiplexer.

 

[Vladis]

I'm not sure how that multiplexer could do what the OP asked for. It might also have been more honest of you to have explained that you make and sell this multiplexer.

Hello,

Yes I make and sell the multiplexer and my aim was to help the OP pointing out to one of many possibilities to solve his problem. He can connect his GPS to my input port P1, his AIS to my input port P2, and my output port P3 to his chartplotter.

Regards, Luis

PS: If my post is against the rules of this forum, I apologise and I kindly ask the administrator to delete my posts and my registration.

 

[pvb]

Yes I make and sell the multiplexer and my aim was to help the OP pointing out to one of many possibilities to solve his problem. He can connect his GPS to my input port P1, his AIS to my input port P2, and my output port P3 to his chartplotter.

Try reading the OP again. He doesn't have a separate GPS - the GPS is in his chartplotter, which only has one port.

 

[Hoolie]

He can:-
connect his AIS from the radio at 38.4k to the chartplotter
connect the GPS signal from the chartplotter at 38.4k to Vladis' device
connect Vladis' device to the radio at 4.8k to transfer GPS data

 

[pvb]

He can:-
connect his AIS from the radio at 38.4k to the chartplotter
connect the GPS signal from the chartplotter at 38.4k to Vladis' device
connect Vladis' device to the radio at 4.8k to transfer GPS data

Yes, he might try that, but the multiplexer's description includes the warning "It is important to note that if the baud rate of the output port is inferior to those of the input ports, data may be lost." So that might not work too well.

The easiest solution is a separate GPS receiver, as I suggested in post 2. This has the added benefit of redundancy in the event of the chartplotter failing.

 

[Hoolie]

I agree the separate GPS is better, but I was just pointing out the NMEA device could be used in this case. I would be surprised if there was a lot of data from the plotter, otherwise it wouldn't cope with a 4.8k setting on its port.

 

[prv]

I would be surprised if there was a lot of data from the plotter, otherwise it wouldn't cope with a 4.8k setting on its port.

Yep - RMC at 1Hz doesn't take much

(It will probably be spitting out GLL, GGA, and a couple of others as well by default, but still well within the capability of 4.8k)

Pete

 

[Heckler]

Hello,

Yes I make and sell the multiplexer and my aim was to help the OP pointing out to one of many possibilities to solve his problem. He can connect his GPS to my input port P1, his AIS to my input port P2, and my output port P3 to his chartplotter.

Regards, Luis

PS: If my post is against the rules of this forum, I apologise and I kindly ask the administrator to delete my posts and my registration.

Bom Dia
não tome conhecimento desta merda!
Continua
Stu

 

[Vladis]

Try reading the OP again. He doesn't have a separate GPS - the GPS is in his chartplotter, which only has one port.

Hello,

Thank you for correcting me. Actually I did not read well the OP problem. But, as it has been said later, "my multiplexer" could make a translation from 38400 down to 4800 or 9600 if the VHF accepts one of these rates.

Best Regards, Luis

 

[dgadee]

I have one of these radios and use a puck for GPS input. I liked it for its simplicity of operation rather than the Standard Horizon. Documentation is poor, though, and not so many dealers about. Changing mmsi number is v expensive. Probably go Standard Horizon when I need want to replace.

 

[FWB]

There’s always the..

Plus crystals.

 

[Mikedefieslife]

I'm going to use a Raymarine SeatalkNG (since that is what I use as my backbone even though I have a Simrad plotter) to NMEA0183 cable. This is a unidirectional cable designed specifically for this purpose. Costs around £25 so not going to break the bank.

Eventually I do want to get a new radio and an AIS transponder, but their are more pressing things to deal with.

I actually have a Garmin Oregon 600 that can output NMEA sentences if I find the right bloody cable.