Seatalk-NMEA-Display

[lockie]

Hi folks;

I'm after a MUX/bridge that will connect my Seatalk and NMEA gear, and display data on an integral small LCD screen.

RS232 or USB to repeat to a laptop would be a nice-to-have, but not essential. I'm very capable with electronics assembly, so a home-brew job would be fine if poossible to keep the cost down. Any suggestions?

Cheers, lockie

[osirissail]

Most electronic nav programs has buried in them somewhere a display pane where assorted ship's data can be displayed from whatever NMEA information is being generated by your various instruments and sensors. You will need a SeaTalk instrument with a NMEA in/out connections or SeaTalk/NMEA junction box to be able to access the information flow and route it to your PC or whatever. All these equipment is easily available. Your new PC - if it does not have a "serial DB9" port will need an adaptor to convert old fashioned "serial" to USB along with a driver. These adaptor cables are also available everywhere. Ebay has lots of this stuff listed for a fraction of the retail costs from boat supply/computer supply stores.

[sandy daugherty]

You won't need the MUX unless you have a lot of NMEA 0183 devices and AIS, which requires a high speed on the chart-plotter port.

[scotte]

Take a look at what Brookhouse has - they sell MUXes that support SeaTalk - allowing you to integrate the SeaTalk bus data into your NMEA bus. They also sell one with a customizable LCD screen that can display any sentences you choose. Very nice products - you'll likely have to purchase directly from the manufacturer in NZ, but shipping wasn't that expensive and didn't take very long at all - a few days.

Brookhouse NMEA multiplexers Home Page

I found this to be the ideal setup for me, which integrates everything together with great flexibility. For example, if I turn off my C70, I still get SeaTalk data on my NMEA bus - so I still have access to wind instrument data. I had some issues due to software bugs in the C70 (confirmed by Raymarine), but with some help from Brookhouse support was able to create filtering rules on the MUX to work around them.

[ActiveCaptain]

I'm using a ShipModul to Bluetooth mux - it's nice having it wireless for laptop use. There are also other options for the output - serial - and I think they have a USB version.

The thing I like about ShipModul is that they handle SeaTalk very well and even convert incoming SeaTalk data into NMEA on the fly so you can get all of the data on your SeaTalk network without the expensive Raymarine conversion box.

ShipModul Marine Electronics

[Captain Bill]

My RL70 Plus has an NMEA 0183 output port that can be setup to repeat almost anything that is available on the Seatalk bus. Currently I use it to send position data to my dsc radio, but additional data can be output that the radio will ignore. Interestingly the RL70 NMEA input conforms to RS-422 (differential input) and the output conforms to RS232 (transmit and ground). I have been considering putting a serial to bluetooth adapter on the output to send seatalk data to my laptop. Does a Raymarine setup that includes a chartplotter/radar display really need a mux? Surely the output from the display does not walk on itself, or does it?

[s/v Jedi]

When you start using your plotter to bridge seatalk to NMEA it won't be long before you get into the dreaded NMEA-loop trouble. We've been there and it wasn't funny... like keeping a GPS position even with the GPS turned off etc.

I join ActiveCaptain and recommend the Shipmodul mux. It's the best one out there afaik and I know a lot of them! The bluetooth option is great but you will need GPSgate to get it to work with MaxSea (no problem, GPSgate is probably needed for other options).

What is so good about the Shipmodul mux is that you can define filters on each input port, create automatic switch to backup GPS etc.

cheers,
Nick.

[Captain Bill]

If I'm only using the NMEA out I don't see how I could get into a looping situation. Since I'm already using the NMEA out to repeat position information that is supplied to the display from a Seatalk GPS, if this was a real problem I'ld already have it. I can see that there might be an issue if I was having the laptop feed data back to the NMEA in, but that is not what I was proposing.

[lockie]

Thanks chaps, maybe a little clarification would help: my set-up is quite simple, with the NMEA output from a basic plotter connected to the autopilot and VHF radio, plus I have a Bidata with Seatalk output. I want to display basic stuff inside the cabin, like lat/long, bearing, course etc from the plotter, and depth and speed from the Bidata.

So all I want is something with one NMEA input, and one Seatalk input, which will display the data. An RS232 or USB output for a laptop in the future would be nice but by no means essential.

Sounds like the Brookhouse unit is the only one so far.

lockie

[r.furborough]

Look at the Raymarine E85001 Raymarine Marine Electronics - PC/NMEA/SeaTalk Interface Box
It will do everything you need and is relatively cost effective.... and for the display look at the Furuno RD30 http://www.furunousa.com/Press%20Art...yacht-RD30.pdf which is designed as a data repeater for NMEA information.

[s/v Jedi]

Lockie: I don't think that Brookhouse is the display you are looking for....

Tell us about your plotter... surely the brand isn't "basic"?

cheers,
Nick.

[lockie]

The plotter is an older Navman (5430 I think), but that doesn't change anything - I'm after a simple display in the cabin (not the cockpit) which will show data from both the plotter (NMEA output) and the Bidata (Seatalk output).

If you know "the Brookhouse isn't what I'm looking for" you presumably know what I am looking for - so what is it?

lockie

[s/v Jedi]

I think the Brookhouse shows NMEA sentences and what you want is a repeater display of the data on your Seatalk and NMEA busses, right? You probably end up with this:

see Furuno RD30 Repeater as just an example (first hit on Google).

Besides that, you need to convert the seatalk data to NMEA and combine it with the plotter output. There's Shipmodul and Brookhouse options.

I checked and see that I was wrong, Brookhouse indeed has a mux with a separate display that can show 1 value with a button to page through the available fields. This is it:

It also has a Seatalk option and the total price would be just under $400.- I think it looks a bit retro but it will be the cheapest solution.

cheers,
Nick.

[lockie]

Thanks Nick. I also see Brookhouse also has something with pretty much the same features, but in a "naked" format for fitting into a custom panel or box. Getting closer, aprreciate all the help..................

I'm really looking forward getting this istalled, to avoid having to climb back out into the cockpit to see all this data when I want to do plots on the paper charts and fill in my logbook. I find that when I've been at it for many hours solo, and finally grant myself a short break in the cabin out of the weather, it's a real pain to have to climb out again because I've forgotten to note all the data. Just another little thing to make life easier.

lockie

[s/v Jedi]

I think your best option is a mux without display and connect the Furuno repeater to that. You have a full display much like their GP-32 GPS and the unit has proven to be very reliable; it's a big step between the two options and I think the price difference is worth it to go with the Furuno repeater.

cheers,
Nick.