Nasa AIS

[rosewood]

Its me birthday tomorrow and am thinking about an AIS. I like the look of the nasa stand alone version. But ive got a standard horizon 180 chart plotter so was looking at the nasa little box thing that plugs into the plotter. Does anyone have any thoughts please on either of these?
Cheers

 

[pvb]

If you have a plotter, it surely makes most sense to display the AIS data on the plotter screen?

 

[maby]

If you have a plotter, it surely makes most sense to display the AIS data on the plotter screen?

Guess it depends on where your plotter is located to some extent. The place for AIS is at the helm where you can see it and act upon it - if your plotter is at the helm, then put the AIS on it. Do check specifications carefully before buying, though. AIS runs at a much higher baud rate than most instruments (assuming you are looking at the NMEA0183 version) - depending on how many ports you have on your plotter and what else you have connected to it, you can hit difficulty - there have been others here in previous years bemoaning their inability to get everything they need hooked up simultanoeusly and talking. If you are not confident that you understand the issues, post a full list of your electronics - current and proposed - and someone here will be able to advise.

 

[rosewood]

Yeah that's what I thought too. My only concern is that the screen on a cp180 is quite small and I was a bit concerned it get too cluttered. It does make more sense though

 

[rosewood]

Guess it depends on where your plotter is located to some extent. The place for AIS is at the helm where you can see it and act upon it - if your plotter is at the helm, then put the AIS on it. Do check specifications carefully before buying, though. AIS runs at a much higher baud rate than most instruments (assuming you are looking at the NMEA0183 version) - depending on how many ports you have on your plotter and what else you have connected to it, you can hit difficulty - there have been others here in previous years bemoaning their inability to get everything they need hooked up simultanoeusly and talking. If you are not confident that you understand the issues, post a full list of your electronics - current and proposed - and someone here will be able to advise.

I have a standard horizon cp180 in the cockpit. Its a Hillyard 9 ton with minimal electronics. I looked at the nasa instructions and the plotter instructions and it looks like they work with each other. I think I will go with the little box "engine" rather than the stand alone one then

 

[prv]

If you have a plotter, it surely makes most sense to display the AIS data on the plotter screen?

I was not particularly impressed with the CP180's handling of AIS data when I had one on Kindred Spirit - although perhaps most other plotters are no better. Simple stuff like range and bearing to a target so I could confirm it visually with compass-equipped binos was not easily available, and the alarm settings were fairly primitive.

Pete

 

[pvb]

Yeah that's what I thought too. My only concern is that the screen on a cp180 is quite small and I was a bit concerned it get too cluttered. It does make more sense though

But the Nasa AIS display is only a 5" screen, much smaller than your plotter! Also, your plotter screen has a far higher definition. And the Nasa AIS display only tracks 30 targets, whereas your plotter can track up to 200.

 

[JimC]

I have the NASA AIS engine connected to a Standard Horizon CP300i plotter and the combination works OK, granted the plotter has a bigger screen than the CP10 but the ships show up clearly.

 

[Caer Urfa]

Its me birthday tomorrow and am thinking about an AIS. I like the look of the nasa stand alone version. But ive got a standard horizon 180 chart plotter so was looking at the nasa little box thing that plugs into the plotter. Does anyone have any thoughts please on either of these?
Cheers

Hows your radio ?, why not buy a SH GX 2100E AIS radio, no messing just plug it into your existing VHF aerial, you will find the AIS works very well with your 180 plotter, then next birthday you can then get a 300i plotter.

The AIS display on the radio is small and can only be used as a back up really, BUT, you will have an excellant AIS display on your plotter.

Mike

View attachment 37169View attachment 37170View attachment 37171

 

[rosewood]

Hows your radio ?, why not buy a SH GX 2100E AIS radio, no messing just plug it into your existing VHF aerial, you will find the AIS works very well with your 180 plotter, then next birthday you can then get a 300i plotter.

The AIS display on the radio is small and can only be used as a back up really, BUT, you will have an excellant AIS display on your plotter.

Mike

View attachment 37169View attachment 37170View attachment 37171

That actually looks a good idea. But I read somewhere that there might be a difficulty with the DSC

 

[Caer Urfa]

That actually looks a good idea. But I read somewhere that there might be a difficulty with the DSC

Had the system in for over a year now and no problems at all with anything nor the DSC functions, my only suggestion is in setting up 'do not' turn all the alarms on ALL at once, try each one in turn until you have 'ON' the ones you really use and want.

This is also the first plotter I have had with an 'inbuilt' aerial, however the reception and quality is excellant plus there are many other user friendly display function you can use. my favorite is 'go to', it's almost an idiots guide to navigating with ETA and distance showing.

Mike

 

[maby]

The potential difficulty with DSC is the NMEA0183 connectivity issue I mentioned earlier. It was discussed at some length around here a year or so ago and revolves around the fact that AIS operates at a much higher data rate than most other NMEA0183 devices. I don't remember the fine detail but there was someone here who bought one of those radios, then realised that because of the other devices he had connected up, he simply didn't have enough ports on his plotter to make it all hang together. Check the installation manuals for everything you will have connected together and make sure that it is possible to connect it all up.

 

[pvb]

The potential difficulty with DSC is the NMEA0183 connectivity issue I mentioned earlier. It was discussed at some length around here a year or so ago and revolves around the fact that AIS operates at a much higher data rate than most other NMEA0183 devices. I don't remember the fine detail but there was someone here who bought one of those radios, then realised that because of the other devices he had connected up, he simply didn't have enough ports on his plotter to make it all hang together. Check the installation manuals for everything you will have connected together and make sure that it is possible to connect it all up.

The GX2100 radio will easily connect to the CP180 plotter. Wiring diagram is here - http://www.standardhorizon.co.uk/fi...rizon Chart plotter to GX2100E Matrix AIS.pdf

 

[maby]

The GX2100 radio will easily connect to the CP180 plotter. Wiring diagram is here - http://www.standardhorizon.co.uk/fi...rizon Chart plotter to GX2100E Matrix AIS.pdf

It certainly will - the problem that the previous thread addressed stemmed from the paragraph in those instructions that reads:

"Port 2 input of the NMEA In/Out Connections in the plotter menu must be changed to AIS 38400 to show AIS targets on the Chart page and the AIS List page. When AIS 38400 is selected, the NMEA output from Port 2 is disabled."

Hence my original message about checking the configuration of the electronics as a whole. The high data rate of AIS introduces incompatibilities with other items of equipment. That radio effectively consumes all the connectivity on the plotter, so the OP does need to confirm that he is not using NMEA for anything else.

 

[pvb]

That radio effectively consumes all the connectivity on the plotter, so the OP does need to confirm that he is not using NMEA for anything else.

It doesn't. The other port continues to output NMEA data. Plotters will usually drive a number of NMEA "listeners", so there isn't a problem.

 

[prv]

It doesn't. The other port continues to output NMEA data. Plotters will usually drive a number of NMEA "listeners", so there isn't a problem.

I guess there is a problem if you want to feed something else into the plotter. I seem to remember that it will display wind / speed / depth / etc, though I'm not sure it's all that useful.

Pete

 

[maby]

I guess there is a problem if you want to feed something else into the plotter. I seem to remember that it will display wind / speed / depth / etc, though I'm not sure it's all that useful.

Pete

Exactly! it probably isn't a problem, but there has been at least one case discussed round here where the purchaser had not done enough research and ended up unable to make all the connections he was expecting. Worth checking before shelling out the money. It could also be a problem if you are driving multiple external devices such as an autopilot as well as the radio - you may need a higher speed for some than others or the ability to filter or configure the message stream. NMEA0183 is a bit of a nightmare when you start connecting large numbers of devices and those SH plotters do not have a large number of independant ports.

 

[pvb]

NMEA0183 is a bit of a nightmare when you start connecting large numbers of devices and those SH plotters do not have a large number of independant ports.

They have more ports than many plotters! If people want to input wind/depth info, a multiplexer might be needed - but it probably would with other makes of plotter too.

 

[wooslehunter]

Got both. They work together reasonably & were easy to install. AIS antenna is on the taffrail (yes I read the pushpit post) & gives way more range than needed. The OP's profile doesn't say where he is. I'm in the Solent & there are lots of AIS transponders around & there is a problem. This is not the first time I've described it here & I have told Standard Horizon with no change in the CP180 firmware. So here goes:


In a crowded area with fast movers, the CP180 AIS alarms are next to useless. The CP180 can be set to alarm when a target is inside a certain range, pAND it's CPA OR TCPA break the thresholds. So, I set the range to 5 miles because the fast movers like the cross-channel cats doing 35knts only take 8.5 mins to do 5 miles. I set the CPA alarm to 0.25nm & the TCPA to 15mins. So anything inside 5nm that will approach closer than 0.25nm causes an alarm. But, that may not happen for a hour, so why do I care. Second, anything within 5nm that reaches TCPA within 15mins will alarm. But the CPA could be 4nm. So again why do I care.

What I really want is to forget the range & set the CP180 to alarm when the target breaks both CPA AND TCPA thresholds. So anything that gets closer than 0.25nm within the next 15mins will cause the alarm. Anyone see a problem with that logic?

So, I use the Mk1 eyeball as the primary lookout (as I should anyway) & then I use AIS to track anything that looks as if it's going to get close enough to make me get out of the way. Second use of AIS of course is to check on the rest of the club racers & see how they're doing......... Shame most of them seem to switch off when they're racing.

 

[prv]

In a crowded area with fast movers, the CP180 AIS alarms are next to useless. The CP180 can be set to alarm when a target is inside a certain range, pAND it's CPA OR TCPA break the thresholds. So, I set the range to 5 miles because the fast movers like the cross-channel cats doing 35knts only take 8.5 mins to do 5 miles. I set the CPA alarm to 0.25nm & the TCPA to 15mins. So anything inside 5nm that will approach closer than 0.25nm causes an alarm. But, that may not happen for a hour, so why do I care. Second, anything within 5nm that reaches TCPA within 15mins will alarm. But the CPA could be 4nm. So again why do I care.

What I really want is to forget the range & set the CP180 to alarm when the target breaks both CPA AND TCPA thresholds. So anything that gets closer than 0.25nm within the next 15mins will cause the alarm. Anyone see a problem with that logic?

This is why I don't like the very basic AIS implementation in many plotters, and prefer the Vesper Watchmate dedicated display instead. It has much more flexible alarm settings (though still not fully configurable in terms of combinations) and also four profiles which can each be set up differently.

I have one profile for empty seas - tell me if anything at all is out there.
Another for cross-Channel and similar circumstances - alert me to things which will pass a moderate distance away within the next 20 minutes.
A third profile for confined waters, which narrows the times and distances right down so that only genuine potential collisions will sound. Also hides stationary targets, which otherwise clutter up the screen around busy ports etc.
A profile for being nosy rather than collision avoidance, which displays all targets but doesn't sound any alarms.

That said, even with the "confined waters" profile available, I generally leave it turned off in the Solent.

Pete