Transceive GPS to iCom IC-M323

[Boh999]

Hi!

Was looking to get GPS into VHF by connecting a GPS receiver to its green and yellow input cables.

However, just changed plotter to Raymarine ES75 and had to install a SeaTalk NG to SeaTalk converter, to get all old instruments into the plotter.

I now have two hubs: the old SeaTalk hub and the SeaTalk NG hub, interconnected. Connected my True Heading AIS transceiver via its NMEA 2000 output port to the SeaTalk NG hub, worked straight out of the box!

iCom IC-M323 supports only NMEA 0183, not NMEA 2000. Can I get the GPS signal it needs for DSC functionality from the SeaTalk/SeaTalk NG backbone, rather than having to mount an extra GPS unit?

Can I even get VHF data into the Raymarine ES75 MFD? (Why would I want it?). I.e. can I connect the
brown (NMEA in - Talker B, Data-L),
white (NMEA in +, Talker A, Data-H),
green (NMEA Out -, Listern B, Data-L) and
yellow (NMEA Out +, Listener A, Data-H)
cables from the VHF to the SeaTalk network?

The colours seem different with SeaTalk:
http://api.ning.com/files/1zNsEY*-C...JIvUdgZd0Hem5cCzhw6dIRiStJWW7irX/e7DSCVHF.pdf

I would rather by a ready-made cable for this than welding, especially with the mix-match of colours between Raymarine vs. iCom above.

The local dealers have no clue, they think 12 V + to the MFD is NMEA out - or something...

Thanks for a good forum!

Cheers

 

[bitbaltic]

I don't do raymarine equipment but a dedicated kit for exactly what you are asking about is made by Raymarine:

http://www.cactusnav.com/raymarine-nmea0183-seatalk-converter-p-13045.html

No idea if it is two way.

Personally I would have handled all these various connections via a shipmodul multiplexer which is capable of directly working with Seatalk, N2k/NG and multiple 0183 options as well as producing a wifi networkand all in a single box. It is more expensive than a single converter but once you start bundling them up....

Hopefully the raymarine experts on the forum will be along with perhaps some better ideas in a bit.

 

[prv]

SeaTalkNG is NMEA2000, SeaTalk1 is its own thing, NMEA0183 is neither of these.

Going from either N2K or ST1 to 0183 for your radio will require a converter. The one BitBaltic links to is suitable, particularly for STng since it already has the right plugs, but there are others out there which will convert from generic N2K. However, all will be more expensive than just connecting a basic GPS module, which being self-contained (you'd power it from the same circuit as the radio so they always come on together) will also be simpler and more reliable.

The output from the VHF to the plotter would allow positions in DSC messages (for example, other people's Maydays, or if you position-polled a friend) to be plotted on the chart. I think most people would consider this optional.

Pete

 

[Boh999]

Thanks Pete and others. I found a GPS Receiver lying around that I can use for the VHF. I also ordered this:

http://www.cruisersforum.com/forums...a0183-to-stng-converter-kit.html#.WUV6IcaezIU

I'm not going down the multiplexer route, will try this instead to get the optional benefits Pete mentions.

I still wonder the following:

1. Does the AIS receive GPS from the plotter when no separate GPS receiver connected to it? Or is it getting GPS from "internal circuits" which explains the poor signal strength? You see, when I run the AIS diagnostics program on a laptop and connect it to the AIS via USB, I the staples are quite low, but when connecting a dedicated GPS Receiver to it it gets better.

2. I take it I can get GPS receive both for the AIS transceiver and the VHF from the SeaTalk NG network, not having to use any extra GPS:s.

If I connect the two extra GPS:s I got, one to the AIS and one to the VHF, will that affect my system negatively, please?

I am thinking it will be better from a redundancy perspective? I could turn off the plotter and still have DSC functionality with the VHF. Or I could turn off the plotter and still have AIS working, please? As we're going on an Atlantic passage not too far in the future, power consumption will be an issue. Perhaps we can turn of the AIS for example, a few hours during daylight. Wouldn't want to turn off the VHF though, but just to analyze all options...

I have seen, perhaps rumours, on the internet, that the plotter will incorrectly get GPS receive from one of the external GPS:s rather than its internal, not something I want, as the ES75 supposedly has a good internal GPS? (Doubt it though, as the AIS had poor signal strength when disconnecting its GPS?). If this is true, then I cannot have extra GPS receivers in my system.

3. Raymarine states in their manuals to connect a power supply to the SeaTalk NG hub. I think they have a pretty good business going on, selling extra hubs and cables this way. As I will be using the 6 pin port on the adapter then, I would need another SeaTalk NG hub to connect further equipment.

I noticed that all my SeaTalk 1 instruments wouldn't turn off if I power supply the SeaTalk NG.

It seems totally unnecessary? It is alive and kicking without that power supply. I suppose it gets power from elsewhere and probably the SeaTalk 1 network is power supplied somewhere (I don't know all the details of the SeaTalk 1 network I got, just know it works).

If I opt-in for the power supply option (thereby loosing an important data port of the SeaTalk NG hub), I would have to route that power via the instruments on-off switch, which involves 1-2 hours of extra labour.

Can I skip that extra power supply, please?

4. If I connect, in parallel (parallel to the SNT>VHF NMEA0183 converter hub), the external GPS to the VHF, will that affect the VHF:s capability to send data to the plotter via the SeaTalk NG network? I would of course want that functionality. Not sure yet what functionality I will be getting but I think possibly: the plotter with mark the boat calling me on the chart, its position. And if I press the Mayday button (DSC) on the VHF it will be plotted on my plotters' chart? If boats in the vicinity press the DSC Mayday button, will that get plotted on my chart? Could be useful if I am close and will aid them?

Cheers

 

[Boh999]

Down at the boat.

Beginning to understand SeaTalk vs. NMEA etc.

Sorry for confusion earlier. Anyway, I cannot find a way to turn on/off GPS output from the chart plotter over its SeaTalk NG port.

I am only using its SeaTalk NG port, not the NMEA 0183 ports. Therefore I must convert back to NMEA 0183 at the Nav station, if needed by any instrument.

My AIS is not Raymarine and does not speak SeaTalk. Therefore I get no GPS input to the AIS over its NMEA 2000 port (the port going into the SeaTalk NG hub).

No harm in connecting a GPS unit to it I suppose.
I will also connect a GPS unit to the VHF. + the SeaTalk NG VHF Converter (converts SeaTalk GPS to NMEA 0183?!?). I will also get DSC into the plotter I hope.
The SeaTalk NG converter will get its power from SeaTalk 1. Will do this summer, we'll see what will happen.