Which AIS?

[BlueChip]

It's some years since I bought any new gadget for the boat but SWMBO says I can have an AIS receiver for Christmas.

It's looking to be quite a complicated choice for me.

I've got a Raymarine RL90 radar/plotter with quite a few out of date C-MAP charts but AIS interfacing to that is not possible.

I've also got PC Maritime's Navmaster software with a load of ARCS charts that I have used and kept updated for years, I like that software but there's no chance of AIS interfacing to the Navmaster system without upgrading to their Superyacht version which I'm not willing to do. Unfortunately it's not possible to transfer my ARCS chart licenses to another plotting package.

I've got the PC card reader for C-MAP so I'm thinking that I should move to a new PC charting package that interfaces to AIS and will let me use my existing C-MAP charts.

I know little about AIS but understand that a 2 channel receiver is the way to go, I probably dont want to go to the additional expense of a transmitter system at this time, but the possibility of upgrading later might be useful.

Does anyone have suggestions?

 

[FullCircle]

I have got my packet of crisps and a bottle of coke, and I am sitting comfortably.

I am moving over to Software On Board SOBvMax by Digiboat (C-Map supported), and looking at the same AIS choice.

 

[BlueChip]

I have got my packet of crisps and a bottle of coke, and I am sitting comfortably.

I am moving over to Software On Board SOBvMax by Digiboat (C-Map supported), and looking at the same AIS choice.

SOBvMax looks interesting, I'm downloading the demo now

 

[FullCircle]

SOBvMax looks interesting, I'm downloading the demo now

Cor blimey this is a bit boring.

I will offer you a Comar AIS2 USB. Spoke with them today, very knowledgable. ASR100 Splitter for stern mounted Glomex VHF antenna.

Masthead is shared with car HiFi so not splittable again.

Seems like 2 channel is the way to go for 200 quid.

If you want to join in and transmit, then 500 quid.

 

[Playtime]

If you want to keep your current chart software, I can recommend Yacht AIS as a separate package - see http://www.y-tronic.com/english/standard_en.htm.

This displays the AIS targets on a separate screen like a radar display. I find this much clearer to view and work with than the same info overlaid on a chart. The current price for the package is €79, cheaper than a new charting package!

Choice of AIS receiver comes down to how much you want to pay. I have the NASA unit and have not had any problems. If you really want a full 2 channel receiver then the Comar unit has been mentioned in previous AIS threads.

 

[forethought]

AIS choice

Unless you have a serious problem with space, then there are better solutions than the ICOM M 505-AIS : it is only a single channel scanning AIS receiver combined with a DSC VHF. As a compact solution with only a single antenna connection for AIS reception and VHF it is very convenient.

But combined with a remote mic needed so you can get at the DSC cancel button (when it starts wailing about a distress call) without going below, it costs well over £500 .....

It uses the main receiver of the DSC VHF to scan AIS1/AIS2 and 16 in AIS mode and makes annoying crunch noises (admitted in the manual) as the squelch opens before the AIS decoder mutes it again. To get rid of them you need to turn the volume to zero.

You can add more channels to scan to the AIS group but it still only receives one at a time.

It also sends the decoded AIS data out at 9600 baud which would not be fast enough if it were a 2 channel parallel receiver.

But it is only single channel and combined with the scanning means it misses AIS transmissions in the Solent where Southampton VTS seems to be commanding slower update rates from ships than the fastest possible - it can be half an hour or so before a nearby (1 nm) moored vessel's name and static information will appear even if you have a 2 channel receiver.

I ended up having keep a persistent store of vessel details (name length draft etc) seen within the last _day_, when I wrote an AIS decoder at work using a 2 channel Comar receiver as the source. My Garmin chartplotter tends to invalidate vessel details when they are 2 minutes old.

 

[Channel Ribs]

Choice of AIS receiver comes down to how much you want to pay. I have the NASA unit and have not had any problems. If you really want a full 2 channel receiver then the Comar unit has been mentioned in previous AIS threads.

Price wise, the NASA comes in at 99.00 and the Comar AIS-2-NMEA at 180.00.

As you say, a considerable difference but the Comar is considered much more reliable.

 

[bitman]

standard horizon gx2100 vhf + ais

if you don't have a dsc vhf kit on your boat... standard horizon has a new fixed vhf radio what includes an ais receiver. in the us this is the gx2100. not sure when it will come to the eu. have a look here http://www.navagear.com/2009/11/standard-horizon-gx2100-vhf-and-ais-all-in-one/

 

[Playtime]

Price wise, the NASA comes in at 99.00 and the Comar AIS-2-NMEA at 180.00.

As you say, a considerable difference but the Comar is considered much more reliable.

On what evidence is the Comar "considered much more reliable" than the NASA? I can understand the arguments about dual channels but reliability is another matter.

In reality I have had no problem with the NASA unit where it matters i.e. crossing shipping lanes, not messing around in the Solent. Several times over the last 3 seasons I have used the AIS info to call up 'problem' ships and in every case the name and other (slow) details have been provided by the unit in plenty of time.

 

[Graham_Wright]

You might want to consider power drain and redundancy.

A stand-alone AIS saves powering up the slave plotter and also allows a back-up if the rest of the kit fails.

 

[eddie2000]

It's some years since I bought any new gadget for the boat but SWMBO says I can have an AIS receiver for Christmas.

It's looking to be quite a complicated choice for me.

I've got a Raymarine RL90 radar/plotter with quite a few out of date C-MAP charts but AIS interfacing to that is not possible.

I've also got PC Maritime's Navmaster software with a load of ARCS charts that I have used and kept updated for years, I like that software but there's no chance of AIS interfacing to the Navmaster system without upgrading to their Superyacht version which I'm not willing to do. Unfortunately it's not possible to transfer my ARCS chart licenses to another plotting package.

I've got the PC card reader for C-MAP so I'm thinking that I should move to a new PC charting package that interfaces to AIS and will let me use my existing C-MAP charts.

I know little about AIS but understand that a 2 channel receiver is the way to go, I probably dont want to go to the additional expense of a transmitter system at this time, but the possibility of upgrading later might be useful.

Does anyone have suggestions?

I too have Navmaster. However, I use SeaclearII which supports AIS, in conjunction with NASA AIS engine. With the CCS program that comes with SeaClearII, you can screen capture your charts in Navmaster and then use them in Seaclear with a little bit of calibration work.
You can find SeaClearII here:- www.sping.com/seaclear/

 

[BlueChip]

I've looked at SOBvMax software and don’t like it. I downloaded YachtAIS but as soon as I run it the demo tells me its expired, so I didn’t get very far with that and gave up. It looks promising though and I will look out for that at the Boat Show and see if I can get a demo off someone.
I've already got a DSC radio and for no good reason other than I had some unpleasant dealings with the company many years in the past I wouldn’t consider anything from NASA.
I like the idea of an AIS receiver powered through USB with an antenna splitter and I am coming round to the idea of having whatever I use to display AIS data separate from my charting software. On the other hand if I upgrade my radar/plotter in a few years I may regret not going for a AIS NMEA receiver.
At least I can now go to the Boat Show with a mission, always makes it much more interesting than aimless wandering around.

 

[FullCircle]

I've looked at SOBvMax software and don’t like it. I downloaded YachtAIS but as soon as I run it the demo tells me its expired, so I didn’t get very far with that and gave up. It looks promising though and I will look out for that at the Boat Show and see if I can get a demo off someone.
I've already got a DSC radio and for no good reason other than I had some unpleasant dealings with the company many years in the past I wouldn’t consider anything from NASA.
I like the idea of an AIS receiver powered through USB with an antenna splitter and I am coming round to the idea of having whatever I use to display AIS data separate from my charting software. On the other hand if I upgrade my radar/plotter in a few years I may regret not going for a AIS NMEA receiver.
At least I can now go to the Boat Show with a mission, always makes it much more interesting than aimless wandering around.

Miniplex and Tinley both do a 38400 Baud input for NMEA Multiplexer, which is wghat I am intending to do, so if I do get round to changing my chartplotter, it will display on that as well.
I have emailed Miniplex today with my potential system diagram.

 

[BrianH]

On what evidence is the Comar "considered much more reliable" than the NASA? I can understand the arguments about dual channels but reliability is another matter.
In reality I have had no problem with the NASA unit where it matters i.e. crossing shipping lanes, not messing around in the Solent. Several times over the last 3 seasons I have used the AIS info to call up 'problem' ships and in every case the name and other (slow) details have been provided by the unit in plenty of time.

Beware so-called dual channel AIS receivers that in reality are single channel in operation, switching channels alternately or based on signal.

I have such a unit (the AIS-2 from San Jose Navigation), which under most conditions performs well with reporting dynamic data sentences but often takes a long time to acquire the less frequent static data transmitted at longer intervals. As this sentence contains the ship's name I often have no ship's name to call if it assumes a threat. In fact, my list of targets is often populated by many objects with constantly updated positions but agonisingly slow to be updated by the static data.

For software I am using the excellent and modestly-priced OziExplorer, the development version of which supports AIS - highly recommended.

One advantage of the AIS-2 is that it is supplied with an antenna and 5M cable and produces both AIS and GPS signals on a single output. I feed this via a serial to USB connector to a PC on the chart table, which OziExplorer can decode effortlessly, displaying both my ship's position and all AIS targets with CPAs.

 

[brians]

AIS Test Report

There was a test of most of the current available units in either YM or PBO in the last couple of months. Can't remember which issue but sure others will advise.

 

[Conachair]

stand alone

You might want to consider power drain and redundancy.

A stand-alone AIS saves powering up the slave plotter and also allows a back-up if the rest of the kit fails.

Would agree with that. I have the nasa unit and it works fine for me, draws very little power and the alarm is half decent volume as well. Tadpole trails usually will tell you straight away is a close quarters situation is coming up, if not a few seconds with a portland plotter will normally show the cpa of other vessels.

 

[Quester]

NAS AIS engine setup with laptop

I have been using a NASA AIS engine with VHF input via an EasySplit VHF splitter and GPS NMEA input for basic GPS (RMC only) strings. The AIS and GPS output is sent at NMEA 2000 , 38400 Bd from AIS engine via a serial to USB converter to my laptop USB port. I also have full GPS strings at NMEA 083 2.0 , 9600 Bd via the COM 1 serial port.

Last couple of seasons I have used ShipPlotter software to display AIS plots and ship data as a radar display in its own window and overlaid this window in a quarter of my screen behind my direction of travel when viewing my chart plotting screen (either CAPN (Maptech raster charts) or C-Map CMAPECS using CM93 vector charts. This set-up gives an uncluttered view of the shipping with range rings to show proximity whilst being able to switch to the main chart (Alt Tab switches the ShipPlotter AIS window on/off).

Next season I will be trying Digiboat’s Software-on-Board with C-Map Max charts which overlays AIS on the charts. I fear that this will all be a bit cluttered but worth a try. The main advantage seams to be that there is a graphic indication on the chart of the closest point of contact with a vector showing the distance off.

AIS is great for seeing ships behind a land mass or behind other ships |(unlike radar but don’t forget the downside of AIS – a lot of craft big enough to cause you grief are not transmitting and therefore invisible..