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Old 17-12-2013, 17:38   #16
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Re: Installing radar and AIS Question

"Your MMSI is globally unique so that is just fine."

I believe some MMSI numbers may not be internationally recognized, those issued by BoatUS (?) for example. Best to check on this unless you don' t plan on leaving USA.

I would get a Class B stand alone unit and connect to your plotter through NMEA 0183 or 2000. Your Raymarine should take one or the other input.
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Old 17-12-2013, 18:01   #17
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Re: Installing radar and AIS Question

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"Your MMSI is globally unique so that is just fine."

I believe some MMSI numbers may not be internationally recognized, those issued by BoatUS (?) for example. Best to check on this unless you don' t plan on leaving USA.

I would get a Class B stand alone unit and connect to your plotter through NMEA 0183 or 2000. Your Raymarine should take one or the other input.
The numbers are globally unique, like he said. That means tha tno two numbers are the same, regardless of where you get it. You boat US number will never be the same as someone from Shrilanka.

What DOESN"T HAPPEN with your boatUS issues MMSI number, is all your contact info does not get placed in the giant international database of MMSI numbers. The effect of that is that rescue staff in Shrilanka receiving your emergency alert won't be able to find out your name, when the boat is registered, or the type and size of the boat. It won't stop them from coming (assuming they would come anyway), and it won't stop your alert from being transmitted or received.

It's not the end of the world, but if you are traveling outside of the US it's definitely better to get a number from the FCC so it gets placed in the international database. You will need to go to them for a ships station license and an operators license anyway since those are required outside the US, and by simply checking a box on the application for your ships station license, you will get assigned an MMSI.

When you go through the process to get an MMSI from Boatus, they ask you if you plan to travel outside the US. If you say Yes, they send you to the FCC.
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Old 17-12-2013, 18:15   #18
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Just to clarify

IMO compliant class A , must have a display and keyboard.

A non compliant class A unit does not have such a requirement , such as a leisure vessel

There. Is no class C receive only spec
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Old 17-12-2013, 19:36   #19
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Re: Installing radar and AIS Question

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The numbers are globally unique, like he said. That means tha tno two numbers are the same, regardless of where you get it. You boat US number will never be the same as someone from Shrilanka.

What DOESN"T HAPPEN with your boatUS issues MMSI number, is all your contact info does not get placed in the giant international database of MMSI numbers. The effect of that is that rescue staff in Shrilanka receiving your emergency alert won't be able to find out your name, when the boat is registered, or the type and size of the boat. It won't stop them from coming (assuming they would come anyway), and it won't stop your alert from being transmitted or received.

It's not the end of the world, but if you are traveling outside of the US it's definitely better to get a number from the FCC so it gets placed in the international database. You will need to go to them for a ships station license and an operators license anyway since those are required outside the US, and by simply checking a box on the application for your ships station license, you will get assigned an MMSI.

When you go through the process to get an MMSI from Boatus, they ask you if you plan to travel outside the US. If you say Yes, they send you to the FCC.
Yes, that is what I was thinking of but could not remember the details. Good explanation. I suppose the FCC route costs a few bucks and the BoatUS way is cheaper so some people may chose that option.
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Old 18-12-2013, 03:38   #20
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Yes, that is what I was thinking of but could not remember the details. Good explanation. I suppose the FCC route costs a few bucks and the BoatUS way is cheaper so some people may chose that option.
The US has MIDs of 338, 366, 367, 368, 369, assigned how do they then break up the MIDs between FCC MMSIs and boatus ( and the others ) ??

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Old 18-12-2013, 03:55   #21
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Re: Installing radar and AIS Question

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The US has MIDs of 338, 366, 367, 368, 369, assigned how do they then break up the MIDs between FCC MMSIs and boatus ( and the others ) ??

Dave
I'm not sure, but the BoatUS number I got some time back was from the 338 block, and the FCC number I got a year or so later was from the 367 block.

And thanks for the clarification on the Class A specs. I guess pretty much everyone making a Class A device goes the extra step to make it IMO compliant. After all, most people purchase Class A in order to be IMO compliant...
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Old 18-12-2013, 03:58   #22
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I'm not sure, but the BoatUS number I got some time back was from the 338 block, and the FCC number I got a year or so later was from the 367 block.

And thanks for the clarification on the Class A specs. I guess pretty much everyone making a Class A device goes the extra step to make it IMO compliant. After all, most people purchase Class A in order to be IMO compliant...
Yes indeed and the provision of a keyboard and display has been taken to quite minimal extremes. In Comars new IMO compliant class A AIS.

Interesting I do see quite a few larger leisure vessels using CLass A.

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Old 18-12-2013, 04:05   #23
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Re: Installing radar and AIS Question

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Interesting I do see quite a few larger leisure vessels using CLass A.

Dave
I've had this exact debate with the Nordhavn community. Most insist on Class A. It seems completely silly to me. I imagine part of it is legacy carry-over from early adopters when only Class A was available. But now I think people feel their boat is more manly if it has Class A. Mine will be a girly boat, I guess, but will still see and be seen just as well.......
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Old 18-12-2013, 08:16   #24
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Re: Installing radar and AIS Question

For a short cruise like the OP is sugesting, Caribbean et al, then class B is fine. But if I was builing a boat for long range cruising I would get Class A.


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Old 18-12-2013, 12:06   #25
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Re: Installing radar and AIS Question

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But if I was building a boat for long range cruising I would get Class A.


Mark
I'm curious why? What parts of a Class A device are important for long range cruising? I ask because I'm building just such a boat, but have selected Class B. Trying to see what I missed.
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Old 19-12-2013, 01:20   #26
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Re: Installing radar and AIS Question

the class A has more transmit power. other boats (or shore) will see you from further away. class A will get ~45 miles B is much less.

you will see everyone else the same with either.
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Old 19-12-2013, 03:20   #27
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Re: Installing radar and AIS Question

I've found that with most pleasure craft, the line of sight limits get you long before the power limit does. In other words, you lose contact because you lose line of sight, not because you run out of transmit power.

I've also wondered just how far away you need to see another ship anyway. 5-10 miles seems like plenty to arrange a safe passing.

In general I feel the same way about radar power. These 40 and 70 miles radars seem kinda pointless to me, both because they won't see most targets that far away anyway because of curvature of the earth, and because I can dodge even the most recalcitrant freighter from 10 miles away. It just seems to be wrapped up in a "more power is better" mentality.

There is a clear advantage to a larger antenna/narrower beam on a radar, and that tends to go hand in hand with a higher power unit. But it's interesting that the electronics companies market the power, not the beam width and/or resolving power.
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Old 19-12-2013, 04:29   #28
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Re: Installing radar and AIS Question

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..... I've also wondered just how far away you need to see another ship anyway. 5-10 miles seems like plenty to arrange a safe passing.
I agree. Not much navigational value knowing about a vessel 15-20 miles away.

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In general I feel the same way about radar power. These 40 and 70 miles radars seem kinda pointless to me, both because they won't see most targets that far away anyway because of curvature of the earth, and because I can dodge even the most recalcitrant freighter from 10 miles away. It just seems to be wrapped up in a "more power is better" mentality.

There is a clear advantage to a larger antenna/narrower beam on a radar, and that tends to go hand in hand with a higher power unit. But it's interesting that the electronics companies market the power, not the beam width and/or resolving power.
It is nice to know if the thunder cell on the horizon is 30 or 50 miles away. I've seen storms out to 60 miles with my 4kw pulse scanner.
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Old 19-12-2013, 04:43   #29
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Re: Installing radar and AIS Question

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\
It is nice to know if the thunder cell on the horizon is 30 or 50 miles away. I've seen storms out to 60 miles with my 4kw pulse scanner.
The Thunder cell doesn't suffer the line-of-sight limitation that a boat on the water does, hence the great range. If you can see them that far out with a 4kw radar, do you feel there would be much more value in a 6kw, 10kw or 25kw?
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Old 19-12-2013, 05:00   #30
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Re: Installing radar and AIS Question

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The Thunder cell doesn't suffer the line-of-sight limitation that a boat on the water does, hence the great range. If you can see them that far out with a 4kw radar, do you feel there would be much more value in a 6kw, 10kw or 25kw?
Nope, 4kw is enough for my needs! But I would question a lesser unit (i.e. Broadband).
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