NASA AIS

[morgandlm]

I am thinking about buying the NASA combined Receiver/Plotter AIS for my Sadler 26. I do not currently have any integrated instrumentation on board but use a Garmin 72 and paper charts for all my Nav work. The AIS will need a GPS input and
I am considering an entry level Garmin GPS to install below to provide the NMEA input. Is there a better, cheap and cheerful way to provide GPS data to the AIS? I'n not too bothered about position data being displayed. I'd be grateful for any advice on this project especially if anyone has experience of the NASA kit. I have an old fixed VHF (not DSC) so I suppose in future I might be wanting NMEA data for a DSC radio if I ever get forced to upgrade.

I'm also uncertain how to provide the signal for the AIS since I keep reading warnings against using a splitter off the masthead VHF aerial cable. Again any advice based on real experience would be gratefully received. The AIS is likely to be for occasional use only - cross channel etc.
Thanks
Morgan

 

[Colvic Watson]

Simple Garmin GPS with a combined data/power cable (£15 on ebay). That feeds the Nasa, you may need a serial gender changer so you have pins to solder the data cables from the Garmin. A separate VHF aerial is about £30 from Cactus and is much better than a splitter, pushpit mount is fine for AIS and with a little adapter thingy it will act as an emergency VHF aerial. It's very simple electrical plumbing. The downside is that the AIS display is very useful in the cockpit and not very useful at the chart table as it's all about confirming and clarifying what you can already see, or in fog what you can't see but is close. The NASA set is, I think, not waterproof.

 

[Scomber]

hi
nasa fine for us with seperate stub antenna on pushpit-it works well and easy to nip down below and have a regular look when the big things are about-took the gps feed out back of garmin plotter feed i think!

I am thinking about buying the NASA combined Receiver/Plotter AIS for my Sadler 26. I do not currently have any integrated instrumentation on board but use a Garmin 72 and paper charts for all my Nav work. The AIS will need a GPS input and
I am considering an entry level Garmin GPS to install below to provide the NMEA input. Is there a better, cheap and cheerful way to provide GPS data to the AIS? I'n not too bothered about position data being displayed. I'd be grateful for any advice on this project especially if anyone has experience of the NASA kit. I have an old fixed VHF (not DSC) so I suppose in future I might be wanting NMEA data for a DSC radio if I ever get forced to upgrade.

I'm also uncertain how to provide the signal for the AIS since I keep reading warnings against using a splitter off the masthead VHF aerial cable. Again any advice based on real experience would be gratefully received. The AIS is likely to be for occasional use only - cross channel etc.
Thanks
Morgan

 

[blackbeard]

I have the NASA and it works well. I have just one aerial with a splitter - works well.
I have a cheap-ish Garmin plotter which provides input to the NASA. Very simple connection, just an ordinary wire connection, again works just fine.
It's a pity the NASA display isn't waterproof, I would prefer it in the cockpit.
You will need to use the NASA in good vis occasionally, just for practice, so you can interpret it. Otherwise, when to fog descends, you will have the display but you will not be able to make use of it.

 

[prv]

Is there a better, cheap and cheerful way to provide GPS data to the AIS?

Yes!

I am a big fan of the BR355 GPS puck:

No display or buttons, just an LED to show it's working and a pair of NMEA output wires. Ideal for feeding position to AIS or VHF kit; mine does exactly that and is mounted under the side-deck where it works perfectly well, so no drilling holes and waterproofing. Sadly the price seems to be creeping upwards these days but here's one for £30 delivered: http://www.ebay.co.uk/itm/NEW-Globa...455?pt=LH_DefaultDomain_0&hash=item337d6a8307

The only snag is that it expects a 5v supply rather than 12v. You get round this using a very simple circuit consisting of a voltage regulator and two capacitors, which converts the voltage for about a quid or so in parts. I made this myself, it's really very easy, but a fellow forumite now offers a ready-made board if you don't like the idea of soldering.

Pete

 

[RIBW]

View attachment 40773

I am thinking about buying the NASA combined Receiver/Plotter AIS.

I'd be grateful for any advice on this project especially if anyone has experience of the NASA kit.

I'm also uncertain how to provide the signal for the AIS since I keep reading warnings against using a splitter off the masthead VHF aerial cable.
Again any advice based on real experience would be gratefully received.
The AIS is likely to be for occasional use only - cross channel etc.

Hi, I have been using the kit illustrated for many years. It is particularly useful in the cockpit in TSS when trying to figure out small relative relative movements of 'threatening' ships - not just crossing the lanes but also when head on to a threat and you are trying to work out exactly what is happening. [At all other times I prefer a simple chartplotter display with AIS].

The GPS position is derived from the Garmin72 - a DIY connector (not Garmin) was bought from the web. At other times the G72 can be disconnected and used independently.
A built in SLA battery provides 12V to both NASA & Garmin, which means it can be moved freely between cockpit and saloon. A 12V input allows power to be augmented from the boat's 12V.
A £2.50 extending whip from Maplins connected to the 259 socket provides plenty of VHF coverage for threatening ships. Alternatively you can jury rig a an antenna on, say, the topping lift or anywhere convenient away from metal.
The metal case provides robust storage for the long periods the system is not in use, transporting home for testing and protection if the weather turns inclement.

Hope that helps
Bob

 

[morgandlm]

Many thanks for the replies. I've decided to go ahead with a separate aerial mounted on the pushpit rail and have ordered the GlobalSat GPS puck to provide GPS data. Fun still to be had getting the aerial coax from the stern neatly into the saloon!

Thanks to all for the advice.
Morgan

 

[doug748]

Very annoying but the NASA needs a smaller plug than the normal VHF thing. So be prepared for that. I have a converter plug that steps down the size but I have no doubt that introduces losses in the signal.

I have had it for years and I think I prefer it to my on deck plotter display. It is not much trouble to nip below on a small boat.

 

[AngusMcDoon]

Many thanks for the replies. I've decided to go ahead with a separate aerial mounted on the pushpit rail and have ordered the GlobalSat GPS puck to provide GPS data. Fun still to be had getting the aerial coax from the stern neatly into the saloon!

Make sure it's the serial Globalsat mouse (BR-355) and not a USB one. I still have some of these left if you would like one...

http://yappelectronics.co.uk/ybw/GPPS.htm

 

[30boat]

I have the Nasa AIS/display and a splitter.GPS is a Garmin 128.Works very well.

 

[morgandlm]

Make sure it's the serial Globalsat mouse (BR-355) and not a USB one. QUOTE]

Can you tell why I should not use a USB version? I assumed that the 353 and 355 and their cables were the same but just the terminations were different.

I have all the other hardware identified now so am nearly ready to go.

Thanks for advice.
Morgan

 

[Heckler]

Make sure it's the serial Globalsat mouse (BR-355) and not a USB one. I still have some of these left if you would like one...

http://yappelectronics.co.uk/ybw/GPPS.htm

John
can I have one please?
Stu

 

[prv]

Make sure it's the serial Globalsat mouse (BR-355) and not a USB one.

Can you tell why I should not use a USB version? I assumed that the 353 and 355 and their cables were the same but just the terminations were different.

Same reason it's no good plugging your telephone into a TV aerial socket. They're completely different signals.

Pete