Installing Radar and AIS Question

[ddsailor25]

Last year we purchased a Raymarine E7D multi function chart plotter. This year I would like to add in the radar and AIS to our sailboat, but as I was reading more about AIS I'm not sure of best options for us. Our plan is to start cruising in about two years which will involve the east coast of the USA down through the Bahama, caribbean, then head west to Panama. As a sailboat I'm more interested in a class B reciever, but do other cruisers find it useful to transmit their location with the class A? Can this also backfire with pirating? If we do go with a class A AIS do we have to go through the FCC application process and how involved is it where we want to sail out of US waters? Or, what happens if you get a MMSI number then decide to go out of the USA with out the application process done?
As you can see I have lots of questions and greatly appriciate all advice.

Dave

[downunder]

Here is a recent thread discussing AIS

http://www.cruisersforum.com/forums/...on-101295.html

If you go to the CF search function and search for AIS there are heaps of threads.

I personally would be looking at the Vesper marine units that has a transponder, wifi and anchor watch functions. Should marry up fine with the Ray system as well as being stand alone.

Vesper Marine: WatchMate AIS Transponders - Dedicated Marine Collision Warning System

[ranger58sb]

If you're sailing outside US waters, your VHF should have an FCC-supplied callsign. Getting an MMSI for your DSC-capable VHF is easy, same form. Using that MMSI for a Class-A AIS (should you chose to install one) follows naturally. The FCC application is relatively easy.

-Chris

[ddsailor25]

I have a standard Raymarine VHF radio that is not digital. So, in order to go with a class A unit I'll have to change that out as well?

[twistedtree]

I think you are confused over the difference between Class A and Class B. Both classes transmit and receive. Class A transmits more info like Next Port, ETA. It also transmits slightly more frequently and with a slightly different algorithm. Also, Class A must have it's own, dedicated control and display panel. Personally I see no reason to spend the extra $$ on Class A.

The difference you are talking about is between a Receiver (receive only) and a Transceiver (transmit and receive). I think a receive-only AIS is foolish for anything other than a backup. I want to see, AND BE SEEN, especially as a slow moving sail boat That requires a transceiver.

[ddsailor25]

Thanks for clearing that up for me. So, with a class B receiver and transponder the radio will need to be digital. Sorry for all the questions. Electronics are not my strong point on a boat. I can replace an engine, but making sure I have all the right electronic components that communicate with each other seems confusing. Thanks

Dave

[twistedtree]

Originally Posted by ddsailor25

I have a standard Raymarine VHF radio that is not digital. So, in order to go with a class A unit I'll have to change that out as well?

No, I don't think any of these things are related. Any AIS transceiver, class A or B, is separate from your VHF. There is no need to change the VHF. Some people use an antenna splitting device that allows both devices to use the same antenna, but they will work with any VHF. If you can install a separate antenna for the AIS.

I'd skip right over Class A devices and look at Class B transceivers. Ignore the new VHFs that have "built-in AIS". They are the source of your confusion, I expect. That "built-in" AIS capability is receive-only and I think it is really spoiling the effectiveness of AIS by leading people to believe they have AIS when they really only have the less important part. Yes, you will be able to see the big ships on your AIS device, but the big ships are the easy ones to see out your window. The bigger problem is whether the big ships can see you, the tiny boat that can't get out of the way or that might be on a collision course.

[DotDun]

Originally Posted by ddsailor25

Last year we purchased a Raymarine E7D multi function chart plotter. This year I would like to add in the radar and AIS to our sailboat, but as I was reading more about AIS I'm not sure of best options for us. Our plan is to start cruising in about two years which will involve the east coast of the USA down through the Bahama, caribbean, then head west to Panama. As a sailboat I'm more interested in a class B reciever, but do other cruisers find it useful to transmit their location with the class A? Can this also backfire with pirating? If we do go with a class A AIS do we have to go through the FCC application process and how involved is it where we want to sail out of US waters? Or, what happens if you get a MMSI number then decide to go out of the USA with out the application process done?
As you can see I have lots of questions and greatly appriciate all advice.

Dave

I'm curious why you believe you want Class A? Class B transponders work well for recreational vessels.

Regardless of Class A or Class B transponder, you should obtain your MMSI number from the FCC is you plan to cruise outside the USA.

Since you already own the RM E7D, you might consider the RM AIS650, it integrates nicely with the E7D allowing software control of silent mode. If that doesn't matter to you, there are several 'black box' units that work well at lower cost.

[ranger58sb]

Originally Posted by ddsailor25

Thanks for clearing that up for me. So, with a class B receiver and transponder the radio will need to be digital. Sorry for all the questions. Electronics are not my strong point on a boat. I can replace an engine, but making sure I have all the right electronic components that communicate with each other seems confusing. Thanks

Dave

No, your (existing) VHF doesn't need to be digital; and AIS transceiver is a completely separate unit, usually with it's own VHF antenna.

My earlier point was that you also need a real VHF callsign outside US waters, which in turn means you should do the FCC application... and while you're at it, getting an MMSI can happen at the same time.

If you eventually upgrade your radio to DSC capable, the MMSI is useful -- to transmit ship's information and location and so forth in an emergency (assuming tied to your GPS).

That same MMSI is what's used in an AIS transmitter.

-Chris

[ddsailor25]

I was confused at the difference between class A and B. Class B is what I'll be looking at. Not sure how others have theirs set up, but my thoughts are it might affect the VHF radio by splicing into that cable and will look to add in it's own antenna off the radar pole.

[DotDun]

Originally Posted by ddsailor25

I was confused at the difference between class A and B. Class B is what I'll be looking at. Not sure how others have theirs set up, but my thoughts are it might affect the VHF radio by splicing into that cable and will look to add in it's own antenna off the radar pole.

Different opinions on whether an AIS transponder should have it's own antenna or share an antenna (via a splitter) with the VHF comms radio. A search on CF will show you all those discussions.

[goboatingnow]

Originally Posted by twistedtree

I think you are confused over the difference between Class A and Class B. Both classes transmit and receive. Class A transmits more info like Next Port, ETA. It also transmits slightly more frequently and with a slightly different algorithm. Also, Class A must have it's own, dedicated control and display panel. Personally I see no reason to spend the extra $$ on Class A.

The difference you are talking about is between a Receiver (receive only) and a Transceiver (transmit and receive). I think a receive-only AIS is foolish for anything other than a backup. I want to see, AND BE SEEN, especially as a slow moving sail boat That requires a transceiver.

Just be aware that only IMO approved AIS needs a keyboard and a display , a leisure class A can be " headless"

Dave

[mub]

Originally Posted by ddsailor25

As a sailboat I'm more interested in a class B reciever, but do other cruisers find it useful to transmit their location with the class A? Can this also backfire with pirating? If we do go with a class A AIS do we have to go through the FCC application process and how involved is it where we want to sail out of US waters? Or, what happens if you get a MMSI number then decide to go out of the USA with out the application process done?
As you can see I have lots of questions and greatly appriciate all advice.

Dave

Dave
In US waters
Class A is for vessels more than 300 tonnes 12W and is really for commercial vessels. It transmits @12W and receives. It allows the user to type a 2 and from field and other useful stuff... tugs in my area often put "TOWING" in their destination field.
Class B also transmits @ 2W and receives. Most units have a "quiet" switch.
Class C is receive only

Anything other than 300 tonnes is not required to have any unit.
Those are not the rules in other flagging countries.

I have a Class B and a Class C unit on the boat.
Although no substitute for careful watch ( blar blar ) there are plenty of times that I have been alerted by the AIS before I have seen an vessel.
I find that knowing if the 125k tonne ship is about to turn is really nice.

As for your choice of Class C or class B or Class A-

Class B has a second GPS - I like the backup.
The switch gets away from the piracy issue... but they have got you on radar any way. Priv
In any traffic zone the more ways you can let the ship know you are there the better IMO
IMO Class A is overkill and requires a whole setup that you don't want to go through.
Class C are the cheapest.


Your MMSI is globally unique so that is just fine.

[twistedtree]

Originally Posted by goboatingnow

Just be aware that only IMO approved AIS needs a keyboard and a display , a leisure class A can be " headless"

Dave

Interesting. All the descriptions I've seen of Class A includes what I think they call a "Minimal user interface". I don't know enough about who owns all the standards that go into it, and like most good standards, they are kept secret unless you buy them :-).

[twistedtree]

"Class C AIS"??? Never heard of it and can't find any reference to such a thing.