Okay I am very very annoyed. I have been using Raymarine for well over 20 years and probably before that. SeaTalk , SeaTalk2, nmea 0183 to SeaTalk, Mostly been very happy. On my second Axiom but come on, this SeaTalk-ng cable is GARBAGE. It could just be called SeaTalk-G . Yes, I realize the concept was good, and they did everything they could to be backward compatible, koodoos for that. But over $50 for a 1 foot cable?? $30 for and end-of-line resister that you can not remove from the connector without breaking it.
What is below is simply a shared opinion from a guy who studied electronics back when transistors were new, was an electrician for 20 years and knows something about electronics and was also in the software business. To some degree, what is here is for my own information, and “works for me”. Most of it is accurate, or mostly accurate and some of it may be wrong. But maybe it will clarify something for you, maybe it will be helpful. I hope so.
So just a word from and old-salt and an electronics guys, go with equipment that uses Device-net if you have a choice. The connections won’t freeze up on you, so you break the cable, end-of-line resister or the instrument trying to get it apart after a few years. AND things will be interchangeable between equipment manufactures.
Will all that bashing, I will explain a bit about what is going on and the backward compatibility challenges they had to deal with. AND while some stuff is ridiculously priced, a real bargain is the SeaTalk to SeaTalk-NG converter block. THIS IS NOT JUST A CONNECTOR BLOCK, There is a data translation circuit in there that changes the NMEA 2000 data stream back to the SeaTalk protocol, which unfortunately is not straight NMEA 0183, (but close).
The yellow ended connector for seatalk normal . Whereas most of the cables have 6 conductors, this cable only has 3. The shield, which is also “ground” or common negative, the red, which is the 12 volt power and the yellow, which is the wire that carries the old seatlak signal information. The wire can pass information from old seatalk instruments onto the NMEA / SeaTalk-ng backbone or visa versa, from backbone to old instruments. As long as your old seatalk instruments are daisy-chained whatever data is compatible will be “seen” by the backbone, and again, visa versa.
The typical spur, with the white connectors has 6 wires/conductors, including the shield . unlike an N2K spur or “drop” it also has this extra yellow wire in it. So old-seatalk instruments can link to each other so when it plugs into the backbone, this yellow wire does not do anything, but if it links between instruments it may be doing something. Here is a helpful link. BUT BEWARE. It looks at the CABLE end, not the connector end, so make sure you flip the image if needed.
The blue wires only have 5 conductors, including the shield. This equates to the N2K/ NMEA2000 backbone. So two for power, positive and negative nominal 12 volts, two for data can L and can H and a shield. The thing is many of us use this stuff on private boats, in the under 50-foot range, or under 40 feet This stuff is all designed for ships, that can be hundreds of feet long. Way overkill in many ways. So if you have do some tinkering, or splicing or use some cat-5 network cable, most of the time IT WILL WORK. Ya know, when you are cursing and can get parts, don’t have transportation, but you have a soldering iron and heat shrink tubing. This stuff is just wires. Data goes back and forth over two of them and power goes over the other two and the shield keeps the bad signals out.
That’s it for now, but I hope to come back and explain a bit more about the cables and what you can and can-not do regarding mixing and matching protocols and equipment. But seriously, unless Raymarine embraces device net, do yourself a favor and take a serious look at:
A) using another brand
B) using a device net backbone, spend a few extra bucks if necessary and ONLY use the SeaTalk-ng network where you absolutely have to in order to connect your Raymarine instruments. Which I will say again, the instruments are very good, top-notch, in in my opinion. the SeaTalk-ng cabling system, which may have been a good idea, is nothing but a headache in its implementation. And because it is a proprietary system, you can’t even get a break from China (Alibaba etc.) which you can get on deviceNet components.
