Class A AIS for $499

[STB]

Hi folks,

I've got one of these EM-Trak A-100 Class-A (Commercial) AIS units and bought it 2 years ago at this $499.00 price, right before they disappeared from inventory everywhere:

Then, they went out of stock everywhere on earth for months to years.

West Marine apparently has them back in stock and on sale at $499.00. No one else seems to have them.
-- https://www.westmarine.com/buy/em-t...0&cm_mmc=EM-_-National_all-_-2021_2_16-_-null

I still think it was one of the greatest bargains I've ever gotten. Even WM's fll price on this unit, $749, was less than other comparable options. For anyone who wants a full Class-A AIS, especially who already has a plotter, you might want it too.

Only nuance I noticed is that, since it is intended for commercial where it shouldn't be turned off, there is no on-off switch. I wired one in-line with the power and put it right next to the unit on the panel.

 

[CaptTom]

Wow, yeah, that is a good price!

No NMEA 2000, no WiFi, but it does support NMEA 0183, so there's still a lot of functionality there.

 

[STB]

Yeah. I ended up using a converter to connect it to NMEA-2000 and, from there, I can send it over wi-fi with the rest.

 

[obthomas]

You can get a new class B transceiver with NMEA 2000 for the same money or less. The only advantage to class A is it tries harder to interact with others in a high radio traffic situation. My class B has always been there for me.

 

[lwarden]

Following this.
I was planning to get a Vesper 8000 but this along with a gateway with Wifi might be a better option.

Perhaps something like this:
https://www.ebay.com/itm/1332485319...LMEy75Yvk1aNcJTgd5CBLyqiqx3yBv28aAslBEALw_wcB

 

[rslifkin]

I wouldn't bother with a class A personally. Then you have to make sure you're good about setting the correct status, etc. I'd just go for one of the class B+ SOTDMA units, as they use the same method to get transmit slots as class A, just with only 5W transmit power instead of 12.5W (but more than the 2W of standard class B).

 

[stevemitchell]

That's a fantastic price on a Class A unit.

You could also go the Class B + route with SOTDMA which is pretty close to a Class A unit in terms of transmit power and trying to get your boat to be "seen" and get a bunch of other integration features like NMEA 2000, etc. but not for that price. The cheapest one I've seen in that world is from AMEC (did a review on it a few years ago at https://seabits.com/amec-widelink-sotdma-ais/) for about $540 at Milltech Marine.

 

[rslifkin]

That's a fantastic price on a Class A unit.

You could also go the Class B + route with SOTDMA which is pretty close to a Class A unit in terms of transmit power and trying to get your boat to be "seen" and get a bunch of other integration features like NMEA 2000, etc. but not for that price. The cheapest one I've seen in that world is from AMEC (did a review on it a few years ago at https://seabits.com/amec-widelink-sotdma-ais/) for about $540 at Milltech Marine.

That AMEC unit is the one I've got my eyes on for adding AIS. To me, it's a good pick not just for the price, but because it can feed AIS data (as well as any other incoming NMEA2000 data) out over USB and wifi (for the version with wifi). Which means I can get depth and other info onto the laptop with OpenCPN without needing an extra piece of hardware.

 

[stevemitchell]

That AMEC unit is the one I've got my eyes on for adding AIS. To me, it's a good pick not just for the price, but because it can feed AIS data (as well as any other incoming NMEA2000 data) out over USB and wifi (for the version with wifi). Which means I can get depth and other info onto the laptop with OpenCPN without needing an extra piece of hardware.

It's a very stable unit and the WiFi piece is good. It's not as good as, say, the Vesper XB-8000 in terms of the features you can tweak in WiFi, but Vesper doesn't have a Class B+ unit unless you buy the Cortex, which is a whole different discussion....

Just like with all of the other AIS transponders, the USB side is always with caveats. Windows-only software in many cases, weird restrictions, etc. AMEC has a Mac version, but it was pretty buggy when I used it to program and change mine. Just have patience if you go this route

The other fun thing with the AMEC is the SD card slot where you can do data logging. Not as useful as Signal K or even the Yacht Devices Data Recorder, but it can come in handy.

 

[pjtemplin]

You can get a new class B transceiver with NMEA 2000 for the same money or less. The only advantage to class A is it tries harder to interact with others in a high radio traffic situation. My class B has always been there for me.

Another advantage of class A is that some agencies only listen to A, not B. Puget Sound VTS is a good example of this.

 

[stevemitchell]

Another advantage of class A is that some agencies only listen to A, not B. Puget Sound VTS is a good example of this.

Puget Sound VTS routinely call out Class B targets from my experience. On foggy days you can call when crossing lanes and they can see you. I've heard them list my boat out in challenging conditions to Washington State Ferries and other Class A / commercial traffic.

They may filter it out most of the time, but they definitely can see it. I wouldn't say that they won't see you if you go Class B.

 

[pjtemplin]

Puget Sound VTS routinely call out Class B targets from my experience. On foggy days you can call when crossing lanes and they can see you. I've heard them list my boat out in challenging conditions to Washington State Ferries and other Class A / commercial traffic.

They may filter it out most of the time, but they definitely can see it. I wouldn't say that they won't see you if you go Class B.

Here's my source. I'm in no position to confirm nor deny, and perhaps things have changed in six years: Adventures of Tanglewood: Upgrading to AIS Class A If I'm wrong, I'm happy to be wrong. Nonetheless, going with class A is a way to avoid this problem altogether, wherever it may exist.

 

[stevemitchell]

Here's my source. I'm in no position to confirm nor deny, and perhaps things have changed in six years: Adventures of Tanglewood: Upgrading to AIS Class A If I'm wrong, I'm happy to be wrong. Nonetheless, going with class A is a way to avoid this problem altogether, wherever it may exist.

Yes I remember that post from twistedtree I don't think it's valid anymore in terms of Puget Sound VTS ignoring or not being able to see class B, as I've heard them communicating with B targets many times in the last few years.

I also have a pseudo-ethical (not sure that's even the right word) conundrum using a Class A AIS transponder on a non-commercial, recreational boat. It's not illegal, and I'm not saying that, but I think there's a reason that a lot of bigger commercial boats filter out Class B - so they can see the things that would really make a big dent if they hit them! Having a bunch of us get Class A would just clutter it up for them, unless we're going very fast or are big enough to make a dent.

I know a friend who has a very, very fast 40' aluminum boat, and standard Class B doesn't spit out updates frequently enough for his speed to be tracked safely. That seems like a potential good case for B+ or maybe A.

Anyhow, just my thoughts...

 

[Jeff F]

I have an em-trak B953 unit on the boat waiting for installation. It seemed like a decent unit for the money when I bought it. Haven't seen them for sale in the US, but in Canada the 5W SOTDMA units start at about $US500.
https://ca.binnacle.com/Electronics-AIS-Systems/c12_479/index.html

 

[CaptTom]

It's a very stable unit and the WiFi piece is good. It's not as good as, say, the Vesper XB-8000 in terms of the features you can tweak in WiFi, but Vesper doesn't have a Class B+ unit unless you buy the Cortex, which is a whole different discussion....

I have a Vesper XB-8000. I was very impressed when it first came out. But it's sort of an orphaned and obsolete product now. No development, no firmware updates, no promised additions to the list of NMEA sentences it'll broadcast over WiFi. And, as you say, no SOTDMA. I'm not ready to spring for Cortex, so I suspect this will be my last and only Vesper.

 

[twistedtree]

Puget Sound VTS routinely call out Class B targets from my experience. On foggy days you can call when crossing lanes and they can see you. I've heard them list my boat out in challenging conditions to Washington State Ferries and other Class A / commercial traffic.

They may filter it out most of the time, but they definitely can see it. I wouldn't say that they won't see you if you go Class B.

That's good to hear, and I think an enhancement since circa 2014. At that time I came through with Class B and called VTS to tell them I was doing something or other (don't recall what). They couldn't find me and asked if I was Class B and said they could only see Class A. I don't know if that was localized, or if it applied everywhere, or if maybe I was just being fed a line. Who knows.

 

[twistedtree]

Hi folks,

I've got one of these EM-Trak A-100 Class-A (Commercial) AIS units and bought it 2 years ago at this $499.00 price, right before they disappeared from inventory everywhere:

That's a great unit, and was relabeled by numerous other vendors. I had the ComNav version and thought I got a great deal for $1200 or $1300 at the time. $500 sure beats that. I did notice them coming down over time, and that's typically precursor to a new model being introduced, which finally happened with the A200. Now they are clearly clearing inventory, and that makes for great deals.


I'm curious what instrumentation data you are feeding it, and whether you have been able to clear all the alarms? From my limited experience, Class A devices are very particular about what external data they will accept, and will perpetually alarm if they don't get it. The alarms can be silenced, but will still be there. At one point I dug up the Class A spec, and sure enough it was all required functionality.


When installing one, there is a fundamental difference between Class A and Class B. Both have their own dedicated GPS, but they are used differently. With Class B, the dedicated GPS is the source of data for AIS transmissions. With Class A, you MUST feed it external data from the boat's primary instrumentation, and the internal GPS is strictly as a backup. Class A insists on:


- GPS (position, COG, SOG)

- HDT (true heading, not magnetic, and definitely not COG)
- ROT (rate of turn)


Is this what you have experienced?

 

[boomerang]

I have a Vesper XB-8000. I was very impressed when it first came out. But it's sort of an orphaned and obsolete product now. No development, no firmware updates, no promised additions to the list of NMEA sentences it'll broadcast over WiFi. And, as you say, no SOTDMA. I'm not ready to spring for Cortex, so I suspect this will be my last and only Vesper.

I, for one , have been very impressed with Vesper, both the company and the product. I agree , their legacy 6000 & 8000 models have been around for a while and lack the B+ advantages. I'm sure they'll be updating the line in the future with a larger selection of B+ units.

The Vesper folks are always available via phone or email for support which is nice and they also make it easy to wipe the MMSI clear from the memory, without shipping the unit to the factory and without a fee, if one decides to take the unit to another boat. I'm not aware of any other manufacturers that offer that service.

I do see the advantage of B+ units & but I don't see the advantage of an A-class model on a recreational boat, especially a slower trawler as ours. I'm fine with our non-B+ vesper 8000B. If everybody had an A class unit, the display would be littered with targets in a busy harbor, which was a driving reason the B-class was developed in the 1st. place.

 

[STB]

That's a great unit, and was relabeled by numerous other vendors. I had the ComNav version and thought I got a great deal for $1200 or $1300 at the time. $500 sure beats that. I did notice them coming down over time, and that's typically precursor to a new model being introduced, which finally happened with the A200. Now they are clearly clearing inventory, and that makes for great deals.


I'm curious what instrumentation data you are feeding it, and whether you have been able to clear all the alarms? From my limited experience, Class A devices are very particular about what external data they will accept, and will perpetually alarm if they don't get it. The alarms can be silenced, but will still be there. At one point I dug up the Class A spec, and sure enough it was all required functionality.


When installing one, there is a fundamental difference between Class A and Class B. Both have their own dedicated GPS, but they are used differently. With Class B, the dedicated GPS is the source of data for AIS transmissions. With Class A, you MUST feed it external data from the boat's primary instrumentation, and the internal GPS is strictly as a backup. Class A insists on:


- GPS (position, COG, SOG)

- HDT (true heading, not magnetic, and definitely not COG)
- ROT (rate of turn)


Is this what you have experienced?

Mine is all hooked up now and getting fed everything it needs to be happy, but as I remember it, it wanted at least the following from external sources: COG, SOG, LAT, LON, ROT, and HDT. And, there were a bunch more optional inputs.

In my case, this was straight-forward to achieve, because they were provided by my Raymarine autopilot's EV-1 sensor core. I was a little worried that the sensor core wouldn't provide ROT because it wasn't listed in the docs, but it did.

When I first installed the unit, and before I got it tied into NMEA, it did "alarm" due to missing inputs. This turned out not to be a big deal because the "alarm" is silent and basically just builds a list of missing inputs and other conditions. I'd turn the unit on, do some other pre-departure chores, and then acknowledge all of the alarms simply by tapping on the same button a few times in a row until they were all ACKed. Once I did that, the alarms didn't appear again, they just showed up in a list of ACKed alarms.

Even disconnected from the NMEA data sources, the unit still worked fine and sent out the data it did have, including the location data from its internal GPS, leaving the missing data empty.

 

[ex-sailor]

I have an em-trak B953 unit on the boat waiting for installation. It seemed like a decent unit for the money when I bought it. Haven't seen them for sale in the US, but in Canada the 5W SOTDMA units start at about $US500.
https://ca.binnacle.com/Electronics-AIS-Systems/c12_479/index.html

I bought and installed this unit last year. Easy install, solid performance. Binnacle has a US "branch" and sells this unit for $599 currently. This model includes an antenna splitter. I still need to install an on/off switch for transmit, but I've been very happy with it in foggy New England.

 

[Frosty]

My perfect world would be a Vesper XB8000 with SODTMA. This is what's been holding me up from buying the 8000. Reason I don't just go with something else is that the additional functionality Vesper has are things I would definitely use. As with CaptTom, I don't see wanting a Vesper Cortex in the near future though.

(Or if the XB8000 price came down, I'd probably be fine without SODTMA in actual fact.)

 

[CaptTom]

My perfect world would be a Vesper XB8000 with SODTMA.

I'm with you there, but I suspect the XB8000 is a dead end. Vesper seems to have dropped it like a hot potato. No development at all for years now. It's too bad they chose to go off in a new direction. I really like the XB8000. And the support (for problems, not enhancements) has always been good.