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Discussion Starter · #1 ·
Like most of us, I try to cut costs whenever possible, and after using a friends Lowrance 3G Radar, I'm seriously considering installing it on my boat, which I think would be a great safety feature when I'm sailing at night. Then I thought about an AIS transceiver, which cost nearly as much as the radar. My wife said stop spending all that money on the boat and don't sail at night - she is deathly afraid of nighttime sailing.

Then I thought about the benefits of having both 3G Radar and AIS, and integrating it all on my Lowrance HDS7 GPS/Plotter. The cost would be about $2,000 for the combination. Of course, if the admiral finds out I'm even considering this, funeral services will be within a week of her finding out I blew that much cash again. ;)

Any opinions from users of either 3G Radar or AIS would be welcomed.

Gary :cool:
 

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2k for the combo ? Would you send me a link . But back to your thread, one or the other? As I see it if I had to choose I would first get radar . Just for the fact that not everyone has AIS , and I'm pretty sure a sea wall or what ever does not either .
 

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I'm intrigued. I've not researched new gen radar but a couple of grand ? Sounds almost too good to be true.
 

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I doubt you can get combo radar and AIS for $2,000


If you are going to sea day or night i would get the AIS first.

AIS can save your life when you screw up.

A radar cant save your life when you screw up. It can only help when you are right on the ball.
 

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I doubt you can get combo radar and AIS for $2,000


If you are going to sea day or night i would get the AIS first.

AIS can save your life when you screw up.

A radar cant save your life when you screw up. It can only help when you are right on the ball.
Huh??? Not sure the guys on the recent Shackelton re-enactment would agree, I'm betting on their final approach to King Haakon Bay, they would have preferred to have radar... :) Radar can have great value as a position-fixing device, after all, especially in a place like this. Radar doesn't 'lie', like charts sometimes can... :)





Depends where you happen to be sailing at a given time, of course... Western Approaches to the English Channel, I might give AIS the nod... Approaching the Maine coast in thick visibility, on the other hand, or tracking the movement of squalls at night in the Mona Passage, radar wins hands down...
 

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Of course, if the admiral finds out I'm even considering this, funeral services will be within a week of her finding out I blew that much cash again. ;)

Gary :cool:
Hey, if ya gotta knock her off ya gotta . . . we understand.
 

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The GX2150 is AIS receive only, I think Gary is looking at transmitting it too.
[Edit]
Beat me to it. Get everything, it's only money
 

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AIS send and receive is the best thing since sliced bread. Those big ships will know you are there! You will know how far away they are, what their course is, and how fast they are going! I dont know how I managed to go up and down Chesapeake Bay at night without it and still remain calm.
 

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Discussion Starter · #12 · (Edited)
I already have the HDS7 GPS/Plotter. Absolutely the best I've come across, very user friendly, incredible resolution, rapid update time, seamless operation.

The Lowrance NAIS-400 Class B AIS system sells for $929 and I've seen it at some internet stores for $100 less. Lowrance NAIS-400 Class B AIS System - LOWRANCE | Marine Electronics

The Lowrance 3G Radar system sells for $1,299 list price, but there are places lowballing it for about $1,000. And, because I have the HDS7, no special interface needed - just an Ethernet cable - that's it. Lowrance Broadband 3G Radar - LOWRANCE | Marine Electronics

So, yeah guys, it's about 2-grand or a bit less for both, when you already have the GPS/Plotter.

Gary :cool:
 

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Oh man, a transceiver for $600. Last I saw one of those babes they were 1k . OK now questions for three hundred . Can I use my chart plotter for a radar screen ? Please give your answer as a question . Thank you Alex .
 

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One is not a substitute for the other, although a lot of people think they are. If you can't swing both now because of finances I would get the radar. I hear so many people rave about AIS, and I agree that it's great, but not everyone has it and those that do (including ships) aren't always looking at it. With radar you will not only "see" all the other traffic, but you will have an excellent navigation tool available to you. I know it's comforting to think that just because the ship sees you on their AIS that the burden is off you, but what about that 80' fishing boat that doesn't have it steaming right for you in the fog? Get both if you can.
 

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AIS send and receive is the best thing since sliced bread. Those big ships will know you are there!
Not necessarily...

AIS Class B Filtering

by Andy Norris, 20 December 2010

Although AIS is a highly useful system for ships and small craft the warnings that I gave in 2006 to AIS Class B users still remain. You cannot rely on your AIS transmissions being picked up and appropriately reacted upon by any vessel. There are numerous reasons for this. The knotty problem of AIS Class B target filtering is only one of these and is probably near the bottom of the list in terms of the potential issues that can cause problems.

Since 2008 all new ship radars have had to include AIS display functionality. It is an IMO requirement that means for filtering of sleeping AIS targets are included on such radars 'to reduce display clutter'. In the list of example filtering modes 'AIS target class A/B' is mentioned. The requirements for filtering are not particularly explicit, especially with regards to its interaction with automatic activation algorithms, which are themselves left to manufacturers to decide upon. It may have been at the back of the mind of some legislators that innovation by manufacturers would be the best way to evolve both filtering and acquisition strategies in these relatively early days of AIS/radar integration. Maybe, in the future, more explicit functionality could then be statutorily defined. Until then, manufacturers will be implementing their own best ideas in these areas.

The problem with AIS Class B targets with regards to filtering is, depending on scenario, you may wish to have a filter that prevents all Class B targets being shown either as sleeping or activated, or you may wish to activate filtered targets under certain special conditions. Class B targets typically apply widely different safety zones compared to interactions between Class A targets, because of their differences in size and manoeuvrability. Particularly in busy areas, small craft often pass closer to ships than is generally considered safe for ship-to-ship encounters, even though needing particular alertness by the small craft skipper.

For this reason, especially in areas that are crowded with small craft but that also have appreciable shipping movements - such as in the Solent area of the UK - it could well be the case that any activation of Class B targets will cause almost constant activation of the Closest Point of Approach (CPA) alarm on the ship - continually distracting the navigating officer/pilot. A 1.0 NM CPA may be appropriate for ship-to-ship encounters in such an area, but many small craft skippers will be quite happy approaching ships at very much closer distances. Therefore, filtering of all AIS Class B targets, together with preventing their activation, may be the appropriate strategy in such areas to avoid possibly dangerous alarm distraction of the bridge team.

Many such areas are found around the world, justifying the inclusion of such a mode in manufacturers' equipment. It should not be forgotten that the bridge windows form the most widely used navigational aid. When operating in busy areas in reasonable visibility they normally form the primary collision avoidance tool.

In inclement weather in such waters it would generally be the correct practice to switch off the AIS Class B filter, considerably improving the probability of identifying small craft in poor visibility and bad radar clutter conditions. In general, there would be fewer Class B targets in such conditions. These would naturally wish to keep a greater distance from ships and, in any case, any detrimental over-alarming of the ships system would, in these conditions, be compensated by the benefits of increased probability of target detection. Of course, in other than crowded waters in good visibility, the AIS Class B filter should generally be switched off.

No normal ship would ever want to ignore the presence of small craft. In most situations AIS Class B transmissions are a useful additional detection aid. In some circumstances, however, Class B filtering is essential to avoid unnecessary and distracting alarms.

Over the next few years it will be interesting to see the strategies that evolve for AIS filtering and activation, especially when combined with evolving radar/AIS association algorithms. Combining radar and AIS data enhances navigational integrity. Used on their own, both AIS and radar have significant integrity issues but the overall integrity of navigation is greatly improved when used appropriately together - and can be enhanced by further integration with other navigational aids. Navigation sensor integration continues to form a highly interesting and relevant research area.

- See more at: Panbo: The Marine Electronics Hub: Class B AIS filtering, the word from Dr. Norris
 

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Discussion Starter · #17 ·
Can I use my chart plotter for a radar screen ? Please give your answer as a question . Thank you Alex .
Much of this will depend upon your chart plotter. Some may require an interface device, but in my case, everything is compatible so just one inexpensive cable is all that's required. You should be able find this information in the User Manual, or by contacting the Plotter's customer service department.

Gary :cool:
 

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We have the 3G radar, it is a great navigation tool, and if I had to choose between radar and AIS, I would choose radar every time. Information on your position in relation to objects around you is invaluable at night or in fog.
Regards,
Tanya
 

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Interesting thread. I was looking to upgrade to radar and decided not to bother. I am heading off for a year and figure if you have AIS and GPS, then radar isn't essential.

IF you don't sail in fog and not much at night. Which I won't.

I think for positioning, gps suffices. I know there is the dreaded "guess what, you are on land now" issue, but with most boats having multiple GPSs, this is very very rare.

Besides, eyeballs beat all, and you don't want to be fewking around dodging reefs at night, they don't show up on radar either!
 
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