AIS: Nasa v Comar

Fascadale

Fascadale

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I want to buy an AIS engine to connect to my SH CP180i plotter.

The Nasa unit is £110+VAT, the Comar £215 +VAT.

In pure performance terms I suspect the difference lies in the Comar monitoring channels A and B simultaneously whereas the Nasa switches between the two channels. (But I may well have got this completely wrong)

On a slow moving MAB is this difference in performance significant?

Is the Nasa unit a dependable and reliable bit of kit?

Will the Nasa connect easily to the SH plotter?

Is there anything else I should be considering?

Thanks
 
We had a NASA engine (mark1) on our last boat - connected to the SH 180i - had a little issue with a few targets - when you rolled over them it rebooted the plotter - neither NASA or SH were interested - blamed the other party!
We noticed the lack of names on a lot of ships - obviously the engine was listening on the wrong channel at the time of transmission - no huge issue though.
We've bought a comar unit for the current boat - and that feeds in to the SH 180i too ... so far no problems to date (other than the lack of alarm filtering on the SH!). Names seem to be there more frequently too - but that could just be my perception.

Oh - plus side for NASA - our first engine had a reception problem - sent it back just over a year after purchasing (yes - I was slow in installing it!) and they repaired it FOC* - actually they replaced the whole board - I know because I'd marked the old one ... so thats a good plus for their customer service

*actually - they said there would be a charge, but they never did charge me.
 
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Have you looked at the Advansea RX100 unit which appears very good? I'm considering it.
 
I wondered about getting some ships with names and some as MMSI.I was told that the bit with the name of the ship is only sent every six minutes which is why it may start as a number and then appear as a ship name.
 
most AIS receivers are built on top of the same chipset. The underlying chipset is now at it's third generation. Nasa AIS receiver is still the first generation stuff, most Comar units are second generation. Third generation is better in all aspects (including real dual channel) . I would see no reason to go for older technology. Third generation units are being retail packaged by Plastimo as Advansea RX100, Watcheye in Netherlands, SI-Tex and many others.
 
testmonkey said:
most AIS receivers are built on top of the same chipset. The underlying chipset is now at it's third generation. Nasa AIS receiver is still the first generation stuff, most Comar units are second generation. Third generation is better in all aspects (including real dual channel) . I would see no reason to go for older technology. Third generation units are being retail packaged by Plastimo as Advansea RX100, Watcheye in Netherlands, SI-Tex and many others.
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Interesting.........thanks

That swings it in favour of the Advansea; not much more expensive than the Nasa unit and a lot cheaper than the Comar
 
I ended up with the Comar because it came as standard with an aerial splitter built in, and also a usb output for my back up laptop plotter. Also their service is also very good.
 
We had a few seasons of poor performance from a NASA engine connected to a Furuno where targets come and go and range seemed to be poor and details were slow to appear.

I have a dedicated ais aerial.

NASA checked the unit and reported it fully working. I borrowed a second NASA engine with alternative cable it performed the same . Some targets stable on my phone AIS app came and went from yachts and training ships in sight less than 5 miles away.

Breaking point was in mid channed with 6 sihps in sight all aboit 2 miles range by radar with us in the middle, NO AIS displayed from those. a couple of Fishing boat 5 miles away was displaying.

We have bought a Comar. Brilliant in comparrison. Things you expect to display do 2-3 times the number of targets, range 30+ miles easily, From Hurst you can see targets at the other end of the Solent and further up and down Cowes and Soton water than i think should be line of sight,

I recomend you go for the Comar.

I should add that both Furuno and NASA were happy to say their kit was working but made no effort too solve what is, i think a comms problem.
 
fireball said:
Oh - plus side for NASA - our first engine had a reception problem - sent it back just over a year after purchasing (yes - I was slow in installing it!) and they repaired it FOC* - actually they replaced the whole board - I know because I'd marked the old one ... so thats a good plus for their customer service

*actually - they said there would be a charge, but they never did charge me.
Click to expand...

So they sold you something which didn't work, and you had to go to all the trouble of taking it out, sending it back, and then reinstalling the repaired unit. And you think that's great service? Great service would be if they built the stuff properly to start with, surely?
 
+1 For advanceSea RX-100. It monitors both frequencies at same time (so better than NASA), connects to my Raymarine C90W chart easily and also connects to OpenCPN on my laptop via USB as well.

No problems so far and it will also multiplex in another slow NMEA signal and output it to the plotter alongside AIS data at 38,400 baud. e.g. DSC distress position data from VHF.

Seems like a good bit of kit at the price. I paid £70-£80 if I remember (special discount) but Marine Super Store still seem to have them at £100.
 
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I have a NASA connected to the CP180I & a pushpit mounted antenna. Seems to work fine.

There is a problem IMO with how the plotter alarms work. I've posted this before & also contacted SH. They are not interested.

It has a range setting beyond which alarms will not sound. Since we get fast moving cross channel cats, which cover 5 miles in around 8.5mins, even a 5 mile setting on this is marginal. So, anything within 5 miles will set off the alarm if TCA OR TCPA is breached. I can turn either of these on or off but I can't set it to AND. So, if something gets to its CPA within 15 mins for instance I get an alarm even if CPA is several miles. Or, if it get's to it's CPA or 0.1nm but takes 2 hours to do it, I still get an alarm. So, in the Solent the alarm is permanent & useless. the best I can do is take the range down to a couple of miles & use the MK1 eyeball to spot the fast movers. But, then AIS would show them up when they are on the horizon.

What I want is an alarm that will sound if CPA is less than 0.5nm AND it's going to happen within 15 mins. I don't care how far away the target is when the alarm sounds. i just know I have to do something about it.
 
pvb said:
So they sold you something which didn't work, and you had to go to all the trouble of taking it out, sending it back, and then reinstalling the repaired unit. And you think that's great service? Great service would be if they built the stuff properly to start with, surely?
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Great service - as in it was outside it's warranty and they fixed it ...

I looked at the board and couldn't see anything particularly wrong with it - it could've been a dry joint or component error/failure. Had it been within a short timeframe of receiving then I'd consider it standard service - but outside that warranty I was pleased (and relieved) when they replaced FOC - they didn't have to.
 
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