Stand-alone AIS

[snowleopard]

I would like AIS having tried it on someone else's boat. The problem is that I don't have a chart plotter and don't really want one. So, does anyone have one of these beasties and is it really any use? The display looks really crude.

 

[RobBrown]

Laptop?

Haven't used that but I installed a stand alone AIS receiver from Comar with a usb feed into my old boat laptop (which also conveniently acts as the powersource for the unit). This can display onto scanned & BSB charts I have using Shipplotter AIS shareware and I also have a copy of the Imray IDC PC chartplotter, which has a (ltd) AIS display facility integrated into the plotter display.

eg
http://www.yachtbits.com/comar_systems/comar_ais_2_usb_pc_ais_engine.php

 

[Juggler7823]

I have used a Simrad AI50 stand alone AIS for 2 years. It needs a VHF aerial but a splitter feed would do. It has its own GPS aerial. It has a (small) chart display that is crude but quite usable and shows any nearby coast line, our boat and other AIS targets. The device helped enormously last year in bad fog and strong tides when our normal chartplotter went down.

 

[doug748]

Your lucky day squire:

http://www.ybw.com/forums/showthread.php?t=283594

So for little more than the cost of the AIS you have plotter + charts thrown in!

The Nasa AIS is fine (I would say that wouldn't I). No flashy features that you might never use and I have found it reliable and esay to use. In fact I might even prefer it to the overlay on my new colour plotter but there we are, I have burnt my boats now.
I have only managed four miles range with a rubber aerial on the pushpit but I have been happy with that, I have no doubt this would be increased if I attended to my continuity arrangements. A lot of folk are not happy with the North Up display but I have found it ok once you get your bonce around it.

 

[snowleopard]

A lot of folk are not happy with the North Up display but I have found it ok once you get your bonce around it.

I'm used to paper charts and tend not to rotate them to the direction I'm going so I'd cope just fine. I'll look into it and get back to you. Could well be interested. Off to work now.

 

[Eygthene]

I've had the NASA AIS "Radar" on board for about 5 years now. I have found it to be an excellent tool for judging which ships are likely to come close enough to require avoiding action. I've crossed from Falmouth to the Isles of Scilly and back every year as well as from Salcombe to Guernsey a couple of times and three crossings to l'AberVrac'h and back. It probably saved our lives when we had a close call from a high speed catamaran ferry overtaking us off the west coast of Jersey.

I get about 20 miles range with a standard VHF whip aerial on the pulpit. The ships are on-screen before they show over the horizon, at the largest scale (32nm) and you can zoom in down to 1nm if they are getting very close.

Unlike many AIS systems, this one shows a "trail" from which it is easy to judge the possibility of a close encounter. You can also see when a ship alters course (as long as your heading does not change).

You can select any particular ship on screen to see its name and MMSI etc.

I stow mine below, but mount it on deck when crossing. It also helps when rounding the Lizard, as, when the overfalls are likely to be bad, I usually pass a few miles off. This is where quite a lot of ships also pass.

Unfortunately, I have seen occasional ships which have not been transmitting AIS despite its being a legal requirement. However I wouldn't be without it.

The north-up display has not been a problem for me, though my crew does not find it convenient.

 

[snowleopard]

The setup I used on the friend's boat had CPA. I would find a set without that facility of very limited use. Do these stand-alone sets do that? Presumably they'd need a GPS feed.

 

[pvb]

The setup I used on the friend's boat had CPA. I would find a set without that facility of very limited use. Do these stand-alone sets do that? Presumably they'd need a GPS feed.

The Nasa AIS "Radar" doesn't show CPA, just the positions of the nearest transmitting vessels (max 24).

 

[BrianH]

The setup I used on the friend's boat had CPA. I would find a set without that facility of very limited use. Do these stand-alone sets do that? Presumably they'd need a GPS feed.

I use OpenCPN (free) on a cheap netbook that calculates CPA and TCPA with alarms.

Some AIS engines will provide both AIS and GPS sentences (my cheapo Taiwan product does) but if not a second USB GPS dongle can provide that.

 

[timbartlett]

The setup I used on the friend's boat had CPA. I would find a set without that facility of very limited use. Do these stand-alone sets do that? Presumably they'd need a GPS feed.

Assuming you've got a GPS input, then yes, many (I'm tempted to say "most") AIS display devices will calculate and display CPAs, and will (if you wish) sort the list of vessels so that those with the smallest CPA is at the top -- but it does depend on the software.

One of the neat things about the Nasa "radar" display is that if any "trail" is pointing straight at the centre of the screen, you know it's a threat. Any that are pointing somewhere else are less of a threat. Once you get used to working with north up, you can quickly tell whether other vessels are going to pass ahead of you or astern, just as you can with real radar.

 

[webcraft]

.
If we are sailing in waters warranting it we use a NASA AIS engine linked in to OpenCPN on a GPS-endongled EEEPC netbook - it gives CPA and works really well.

- W

 

[tarik]

AIS Problem

Advice please.

I have fitted an AIS engine with separate AE also installed OPENCPN on my laptop, I'm getting absolutely nothing - what am I doing wrong?

Hopefully its something simple - yes I have switched the laptop on !!!

As ever - very grateful for all replies.


David

.
If we are sailing in waters warranting it we use a NASA AIS engine linked in to OpenCPN on a GPS-endongled EEEPC netbook - it gives CPA and works really well.

- W

 

[Conachair]

I would like AIS having tried it on someone else's boat. The problem is that I don't have a chart plotter and don't really want one. So, does anyone have one of these beasties and is it really any use? The display looks really crude.

I have one and it's one of the best gadgets on the boat. Very low current draw and works down at low voltages. The "tadpole trails" show in an instant which ones you need to keep an eye on. Quite a loud alarm as well.

For day to day usefulness against cost this one is up near the top.

 

[snowleopard]

I have one and it's one of the best gadgets on the boat. Very low current draw and works down at low voltages. The "tadpole trails" show in an instant which ones you need to keep an eye on. Quite a loud alarm as well.

A question on that - if the tail is heading for the centre of the circle, is it going to hit you or pass behind, i.e. are the directions relative to your current position or to your motion?

 

[Conachair]

A question on that - if the tail is heading for the centre of the circle, is it going to hit you or pass behind, i.e. are the directions relative to your current position or to your motion?

relative. If the tadpole is pointing at the centre then you really should be thinking of doing something

I've used a portland plotter on mine before to have a look at where the ship would go if I stopped, using the ships true heading from the side bar.

Offshore I've watched ships a few miles away change course to miss me the go back on course once clear.

The low power draw is great, 0.1a , leave in on all day without a worry.

 

[PaulR]

we have had the nasa unit for several years - simple to use - straightforward to interpret - for us a winner (mind you we do not have a chartplotter set up so standalone makes sense for us)

 

[RichardS]

Advice please.

I have fitted an AIS engine with separate AE also installed OPENCPN on my laptop, I'm getting absolutely nothing - what am I doing wrong?

Hopefully its something simple - yes I have switched the laptop on !!!

As ever - very grateful for all replies.


David

Don't mean to suck eggs etc but you do have GPS enabled and charts installed on the laptop?

Richard

 

[BrianH]

Advice please.
I have fitted an AIS engine with separate AE also installed OPENCPN on my laptop, I'm getting absolutely nothing - what am I doing wrong?

Your first step should be to ensure you have the correct parameters set in the OpenCPN toolbox for both GPS and AIS COM port(s), including the GPS input nmea baud data rate. How you ascertain the COM port depends on your operating system, but there are utilities you can download for that.

If you are sure you have all parameters correct and still have no input, perhaps you have no AIS targets within range? If, however, you are testing where you are sure commercial ships are nearby then you need to test if the AIS receiver is outputting nmea sentences into the computer by monitoring via terminal mode or another utility.

For COM port splitting, or debugging, you may find XPort useful.

 

[snowleopard]

Advice please.

I have fitted an AIS engine with separate AE also installed OPENCPN on my laptop, I'm getting absolutely nothing - what am I doing wrong?

The first thing I'd look at is the settings of the two devices. Almost certainly they don't match. They must both be using the same version of NMEA e.g. 0183 and the same baud rate. You also need to be sure the AIS is putting out its signal in the format the laptop expects, e.g. serial, usb or firewire.

 

[tarik]

AIS Connection Problem

Very many thanks to all who have come to my aid ! I've printed the thread and will go back to the boat next week end, hopefully with somebody who understands rocket science !!


best wishes and good sailing


David

Advice please.

I have fitted an AIS engine with separate AE also installed OPENCPN on my laptop, I'm getting absolutely nothing - what am I doing wrong?

Hopefully its something simple - yes I have switched the laptop on !!!

As ever - very grateful for all replies.


David