Cheap/Easy AIS transponder

[AedanC]

Originally Posted by George_SD

Cheapest AIS transponder that I can think of is the iCOM M94D

$300 handheld AIS+VHF with DSC

https://www.westmarine.com/buy/icom-...3?recordNum=17

That's a VHF tranceiver with a built in AIS receiver, it cannot transmit AIS so it's not an AIS transponder/transceiver.

[Statistical]

Originally Posted by muttnik

* I'm personally unaware of how widely this tech is deployed in transceivers or if the ITU recommendation that it be limited to class A was adhered to (I'm guessing yes)

Here is one study from two years ago

However, the use of the AIS3 and AIS4 channels is still not widespread, with only 17,531 out of at least 68,161 vessels detected using the AIS3 and AIS4 channels versus the AIS1 and AIS2 channels, as shown in Table 2. In 2014, the number of AIS3 and AIS4 reporting vessels was estimated to less than 2 300 using an ASR100 type receiver on the International Space Station [22, 28]. With a linear adoption rate, the full fleet adoption of the AIS3 and AIS4 channels is not expected for another 14 years.

https://link.springer.com/article/10...67-019-00245-z

Some other interesting conclusions:
* Use of AIS 3/3 & msg 27 made vessels about twice as likely to be seen in high traffic area.
* Saturation limit using AIS 3/4 & msg 27 is about 11,750 vessels transmitting within the satellite field of view vs 1,750 for "standard" AIS.
* Satellites even in 2019 are not fully optimized (either lack 4 channel receivers are secondary payloads so antennas not optimized for AIS reception).

One thing is I have seen conflicting reports on if msg 27 and AIS3/4 chanels are available on Class B+ trasponders. The fact that no manufacturer of B+ devices make such claims leads me to beleive that even if it is allowed it isn't being done to save cost although I would be happy to find out I am wrong.

[s/v Jedi]

Satellite AIS is supported in all new class-A and class-B SOTDMA transceivers. If you have a class B SOTDMA transceiver then you have satellite AIS.

Even though some think this is of no use for cruisers, they may change their mind if they ever require search and rescue to find them. I think it’s chilling to find that people think AIS is only for collision avoidance...

Here is a table showing which transceivers (not complete) support satellite AIS: https://www.milltechmarine.com/custo...comparison.pdf

[muttnik]

Thanks statistical and Jedi: Both interesting links

Originally Posted by s/v Jedi

Even though some think this is of no use for cruisers, they may change their mind if they ever require search and rescue to find them. I think it’s chilling to find that people think AIS is only for collision avoidance...

I confess to valuing AIS for collision avoidance in a limited set of scenarios which is why outside of those scenarios it gets turned off with the other non-essential electronics [EDIT: obviously if required by local legislation which was the point of the OP, it would also be on]. I do understand your point but having thought for the past 10 minutes as to whether I should worry that I'm squandering a potential safety benefit to supplement for the sake of a mere 7.4W nominal...I'm ashamed to say that I don't and will doubtless continue to rely on epirbs and plbs if the worst should ever happen.

[Statistical]

Originally Posted by s/v Jedi

Satellite AIS is supported in all new class-A and class-B SOTDMA transceivers. If you have a class B SOTDMA transceiver then you have satellite AIS.

Even though some think this is of no use for cruisers, they may change their mind if they ever require search and rescue to find them. I think it’s chilling to find that people think AIS is only for collision avoidance...

Here is a table showing which transceivers (not complete) support satellite AIS: https://www.milltechmarine.com/custo...comparison.pdf

Thanks for the very good cite. Glad to see my B600W supports it. I am surprised more Class B SOTDMA ("B+") manufacturers don't tout the improved satellite reception. If nothing else it would make good marketing.

Also I agree it is very unlikely that a cruiser would ever need this capability but it they do they will be very glad they have it.

[IslandHopper]

Originally Posted by s/v Jedi

Satellite AIS is supported in all new class-A and class-B SOTDMA transceivers. If you have a class B SOTDMA transceiver then you have satellite AIS.

Even though some think this is of no use for cruisers, they may change their mind if they ever require search and rescue to find them. I think it’s chilling to find that people think AIS is only for collision avoidance...

Here is a table showing which transceivers (not complete) support satellite AIS: https://www.milltechmarine.com/custo...comparison.pdf

You just don't give up do you, even though it's plainly obvious that the whole Msg 27 is still a new novelty to you it's ancient tech and has been around for over 10 years!

And just because i didn't mention anything other than Collision Avoidance you assume i think AIS has no other function?? thats nothing more than a desperate argument from someone with no argument at all....I've been using Class A AIS everyday since it's inception and have owned my own Class B's since they became available, and used them in all of there intended uses!... you just can't help putting words into other peoples mouths can you?!

But go ahead and have your 15 mins of fame believing you are the bearer of new information, joke....

[Emoyeni]

Thanks for this post. Gosh I really want to get one if it's this cheap. Can anyone confirm if any of the "brand name" AIS units are not made in China? Ideally I won't directly or indirectly support genocide with my purchases...

[Simi 60]

Originally Posted by Emoyeni

Ideally I won't directly or indirectly support genocide with my purchases...

Yeah, have fun with that
America and Canada make the list as does Australia.
What are you typing your response out on?

https://en.m.wikipedia.org/wiki/Geno...genous_peoples

https://en.m.wikipedia.org/wiki/List..._by_death_toll

[Emoyeni]

Originally Posted by Simi 60

Yeah, have fun with that
America and Canada make the list as does Australia.
What are you typing your response out on?

https://en.m.wikipedia.org/wiki/Geno...genous_peoples

https://en.m.wikipedia.org/wiki/List..._by_death_toll

I don't want to take this thread off track; I will just say this: I can't have any effect on what happened centuries ago. I can do a teeny bit about what's going on now. Just in case you are curious: https://www.bbc.com/news/world-asia-...ynp9_3GIOSmxWY

If I have a choice between Chinese products and those of most other countries, I'm going to go for the other countries after reading the above article. Pretty simple.

[Simi 60]

Originally Posted by Emoyeni

I will just say this: I can't have any effect on what happened centuries ago.

Bad stuff happening in the above mentioned countries now, no need to go back centuries.

I'll just leave this here
https://www.hrw.org/world-report/202...hapters/canada

If I have a choice between Chinese products and those of most other countries, I'm going to go for the other countries after reading the above article. Pretty simple

Again, what are you typing your response on?

[bobnlesley]

Another vote for Matsutec We crossed the Pacific using their 33A unit with its own antenna mounted on the rear goal posts; it worked well, indeed the GPS on it rarely 'lost signal', which happened quite regularly with both our Garmin 128 fixed GPS and the chart plotter's dongle, to the extent that I rewired the cockpit repeater to the AIS rather than the Garmin unit - you need to do something for entertainment on a long passage

[Franziska]

This. Typical type B transponders do not transmit satellite data.
They rely on an external or internal GPS to get a position, speed and direction which is than augmented by the ships details and call sign before it is broadcast on a special VHF frequency which other AIS receiver can pick up.
Typical range is like any VHF radio.
They do typically not broadcast other ships data.
Type A systems on commercial vessels may do more.

The satellite AIS is mostly based on satellites which can specifically receive VHF AIS signals.

Originally Posted by IslandHopper

I thought that was fairly well know these days, a quick look at MarineTraffic will clear that up.

I should add that AIS Transponders have not been designed with the aim of transmitting to Satellites, they are still a terrestrial transponder, satellites have been launched with receivers aimed at picking up the AIS signals.

[s/v Jedi]

Originally Posted by IslandHopper

You just don't give up do you, even though it's plainly obvious that the whole Msg 27 is still a new novelty to you it's ancient tech and has been around for over 10 years!

And just because i didn't mention anything other than Collision Avoidance you assume i think AIS has no other function?? thats nothing more than a desperate argument from someone with no argument at all....I've been using Class A AIS everyday since it's inception and have owned my own Class B's since they became available, and used them in all of there intended uses!... you just can't help putting words into other peoples mouths can you?!

But go ahead and have your 15 mins of fame believing you are the bearer of new information, joke....

Wow, you Aussies are pretty dense in your comments, aren’t you? There is nothing new or different in your posts than what I write, yet you seem to have the desire to make it sound like I post some terrible falsehoods. You must be Sith, bashing the Jedi, I get that
I got a class-A transceiver in 2005 so that puts me 5 years ahead of you. Furthermore, I got that because I helped design & develop it so please spare me your spread of knowledge on the subject because it doesn’t even touch my first day of study on the subject

When you would have looked up the ITU specifications for AIS then you would have found that satellite AIS incl. Msg 27 is an addendum. Google the definition of that word, it means it wasn’t part of AIS before the addendum was written.

So what is new to most cruisers is the class-B SOTDMA transceivers: all who got AIS early, got class-B CS transceivers and are still using these today. They don’t do satellite AIS. With the receivers and CS transceivers everybody learned that AIS uses two channels that are up high in frequency so that special AIS antennas were marketed, tuned at 162MHz instead of 156.8MHz. Those antennas are unsuitable for use as VHF antennas because VSWR is worse than 2.0:1 at 156.8 MHz.

As antenna splitters for use with AIS were invented, Vesper came out with an antenna that could do both VHF and AIS.

Now we got the SOTDMA class-B transceivers with satellite-AIS. Just like the class-A transceivers have (they are SOTDMA). It means that when you have one of these, you need a broadband antenna like that Vesper antenna.

Another good choice is a Phase III antenna from Shakespeare. The correct version is the 6500-WB. It requires an additional ferrule for mounting on a 1”-14 threaded base.

For more in depth info on the history of satellite AIS, this ITU document from 2009 is a good start as it is the proposal for it incl. the reasons for the new msg27 and the two extra transmit-only channels.
https://www.itu.int/dms_pub/itu-r/op...2009-PDF-E.pdf

[olddog57]

A bit offtop, but I think close enough to put my question here.
I have Standard Horizon DSC-VHF (with AIS receiver built in), and I have an Axiom chartplotter.
It is very easy to initiate a DSC call to an AIS target with the above VHF, but should I install an AIS transponder and connect it to the Axiom - will I be able to connect to these the VHF and then to place DSC calls on AIS target through the Axiom? Which , if possible, should be more convenient than through the VHF with its small screen).

I should add, the VHF only has the NMEA 0183 interface, while bith Axiom and AIS have NMEA 0183 & NMEA 2000

[DavidN]

Hi,

Sorry if this has already been answered but i thought i would try and help not having read the full post but here goes in answer to the original question......

I found the Alltek Marine Electronics Camino 108 to be about the cheapest AIS class b transponder out there, i think i got mine for $379 which was way cheaper than the raymarine, garmin or navico ones and its worked flawlessly for 2 years now.

It was almost plug and play, took about 20 mins to set up. You can use a splitter to get AIS data from the vhf antenna however I just bought a $30 antenna off Amazon, bolted it to my Bimini and it works a treat. I have heard it's best to seperate the antenna for vhf and ais but not sure if that is true. Once you put in your vessel data via the usb cable they give you connected to software on your computer and set the mmsi number in the unit (be careful as it locks it in once you put it in) i connected it to my mfd via nmea2000 and it all worked without a glitch. It receives and transmits ship data via the ais antenna attached to it that i believe is a constant process but then gets the gps location from a gps antenna provided for those messages it sends. Power draw doesn't seem that high but it's hard to tell and i've not tested it but maybe the specs for the AIS transponder you choose will have the power draw listed.

I would advise anyone to get one as in a squall the other night at 3am I literally couldn't see the oil tanker 500 meters in front of me and i am not sure he was looking for a small sail boat offshore at 3am so i made sure i let him past across my bow as he wasn't stopping. It was the AIS that made me see him in time with an alarm i've set up to warn me if a vessel comes within 1nm when moving.

Cheers

David

Originally Posted by Boatguy30

With NZ and Fiji currently requiring AIS passage “verification” and I think Thailand already had, need to fit an AIS transponder. Currently have a receiver incorporated into my VHF.

What is the easiest way to go about this? Separate antenna on the stern arc? What AIS are the cheapest and lowest power consumption.

Also does AIS only ping to satellite when you encounter a ship that transmits the data? This is what I’ve been told and considering we saw very few ships between French Polynesia and NZ, it makes this ridiculous “verification” even more annoying!