Electronics fit

[BogMonster]

Time to start thinking about electrickery for the new boat

I'm pretty much set on a basic non DSC Icom for the VHF, as far as I know the DSC functions are next to useless here so may as well save some money.

Nobody makes an AIS-receiving chartplotter as far as I know, so a chartplotter is probably a waste of time and likely to be deleted to save money. If I could get AIS positions I might be interested in it.

So that will mean a basic GPS that will show speed/position/course on one screen like the one I have (GPS72 which depending on who you listen to, may or may not be available) would be fine. If I can't get a GPS72, what would you recommend for something similar?

So ... what about fishfinders? I have a Piranha 1 on the Humber which is OK but loses the signal over about 20kt however I think that is down to location of the sounder on the transom, anyway it no longer appears to be made. New boat will have the sounder built into the hull. The Eagle Cuda 128 seemed to be one often recommended, but now also no longer available. All I want is something basic to show the water depth and the shape of the bottom plus any whales that happen to be underneath me - any recommendations? Fancy colour display not needed.

Thanks

[willk]

I can't really help with product suggestions, but I do have a few thoughts on the general plan.

First off, I'd say get the DSC VHF (you won't save much not getting it) as with the growth of the oil industry you will find more monitoring of the system around you. In any case, any other DSC VHF in the Falklands will react to a Distress Alert from your's. I think you'd be MAD not to .

AIS is available on this DSC VHF, it's a Furuno brand. It will pass the AIS signal to a plotter but I think has a small schematic AIS display itself.

As you will be short of console space, I'd suggest linking that general type of VHF to a small combi plotter/sounder. This kind of kit costs about £400-£600 depending. Obviously you'll need to be sure the plotter in question WILL display the AIS data.

This leaves you with two electronic units on your console plus a compass. The plotter may have an internal antenna and your transducer is in hull. The VHF/AIS requires only one antenna and no splitter box.

All in all a tidy physical package and with transducer, antenna and chart (if available?) should be doable for well under £1000 ex VAT.

EDIT: Forgot to say that the DSC VHF should show your position, heading, speed and time, which is handy if you are using the entire plotter display in Sounder mode

[Erin]

I think if you do a search under the make 'digital yacht' I seem to remember they do a combined AIS plotter. IIRC

[Channel Ribs]

Originally Posted by Erin

I think if you do a search under the make 'digital yacht' I seem to remember they do a combined AIS plotter. IIRC

Yep, they do indeed.

And as willk says there are a few DSC AIS units about, perhaps the best value being the Navicom one.

The Garmin GPS72 is still listed in Garmin's price list, you should be able to get one for about 110 or 130 with the marine mount etc.

You can get a 451S with fishfinder transducer for under 400 quid and a Navicom DSC AIS for 250.

[BogMonster]

Interesting, thanks...

I presume it is this one http://www.digitalyacht.co.uk/produc...oducts_id=1120

I don't really understand DSC but I thought DSC needed MMSI vessel registration to work? as far as I know we don't have that here.

One other question I have is that if I went for a plotter, it would need to be one which has charts of the Falklands area, and I don't think most of them do. I know charts covering this part of the world exist, but I think only in limited formats. Does anybody know how to check on this?

What do I need to specify to make sure all these instruments talk to each other? I'm dimly aware of NMEA something or other but it's a bit of a closed book to me

[Channel Ribs]

Originally Posted by BogMonster

... it would need to be one which has charts of the Falklands area...

What do I need to specify to make sure all these instruments talk to each other?

The Falklands are in with the Chile chart in the case of Garmin, not sure about the others.

NMEA is the way to go, not a catchy name for something which in reality is easy enough to wire up.

[Cookee]

Originally Posted by BogMonster

I don't really understand DSC but I thought DSC needed MMSI vessel registration to work? as far as I know we don't have that here.

What do I need to specify to make sure all these instruments talk to each other? I'm dimly aware of NMEA something or other but it's a bit of a closed book to me

The MMSI number is just a number you put into the radio and is transmitted when you press the emergency button, you may find you need to put a random number in to get it to work or not, but it will still transmit your position if it is connected to your GPS via the NMEA wires - easy enough to do, and if you get compatible GPS and VHF sets they will not only send your position in case of an emergency, but also plot the position of any emergency received!

[Poly]

Steven, Google suggests a FI vessel should have an MMSI starting 740xxxxxx - and that there are certainly a few large fishing vessels registered with 740 numbers.

[BogMonster]

Thanks, I see 740 codes for several vessels I know on the local register so I might contact the FI fishing companies and see what they say about who issues the codes. Would hate to pop up on all the panic alarms saying somebody else was sinking

Back to NMEA there seem to be two sorts basic NMEA0183 and a more whiz-bang NMEA2000, which one do we all use these days?

[Cookee]

Originally Posted by BogMonster

Thanks, I see 740 codes for several vessels I know on the local register so I might contact the FI fishing companies and see what they say about who issues the codes. Would hate to pop up on all the panic alarms saying somebody else was sinking

Back to NMEA there seem to be two sorts basic NMEA0183 and a more whiz-bang NMEA2000, which one do we all use these days?

For this purpose I believe 0183 is fine - 2000 is for stuff like engine information displayed on your GPS

[willk]

Originally Posted by malthouse

The Falklands are in with the Chile chart in the case of Garmin, not sure about the others.

Hmm. I wonder what the Chileans call them? It would be VERY IRRITATING for Mr. Luxton if they used the nomenclature favoured by their immediate neighbours (not that there's any love lost there either)

[Erin]

If you can, I'd would go for NMEA2000 on all your equipment. It is so much easier to hook up, with proper matching plugs and sockets rather than soldering wires together etc. It aslo means you can easily upgradde items in the future with less risk of obselescence. 0183 will get gradually phased out I would think.

[wavelength]

when I was in Chile and teling the locals I was on the way to the falklands, I mentioned malvinas they said no no here it is the falklands. Not a great deal of friendly neighbourly relations with chile and argentina eh

[willk]

Originally Posted by wavelength

Not a great deal of friendly neighbourly relations with chile and argentina eh

I've had the "pleasure" of crossing that border just the once - there's not much joy at Immigration

The Irish Passport did no harm either side , Gen. Bernardo O'Higgins on one hand and Las Malvinas Fever on the other

[BogMonster]

A (probably thickie) question ... what is the relationship between DSC and AIS?

I'm looking at the Icom ICM411 DSC VHF, and the Garmin GPSMAP 551s in particular, and I downloaded the Garmin manual to see what it can do.

The Garmin says that you can "view information about other vessels" if connected to a DSC or AIS system so what is the difference between "DSC information" and "AIS information"?

[Poly]

Originally Posted by BogMonster

A (probably thickie) question ... what is the relationship between DSC and AIS?

I'm looking at the Icom ICM411 DSC VHF, and the Garmin GPSMAP 551s in particular, and I downloaded the Garmin manual to see what it can do.

The Garmin says that you can "view information about other vessels" if connected to a DSC or AIS system so what is the difference between "DSC information" and "AIS information"?

Exactly what information you can see is going to depend on exactly which reciever / plotter you have, and of course what the other person has/is transmitting. But here is what you might be able to get:

DSC data fed to a plotter
If someone transmits a DSC distress call by holding down the red button expect to see their position on the plotter.

If you have a "friend" who's MMSI you know, you can 'ask' them (digitally) their position and it will show you on the plotter. As far as I know you need to know who you are asking so its not covering all vessels - and probably isn't set up to automatically ask every 5 minutes so update (although some might do this?).

AIS
Vessels with AIS transmitters (mostly large commercial vessels, and yachties with money to spend on toys - but probably not the Navy) send out their MMSI, speed, direction, size etc. Your plotter can then show the position of these (if suitably enabled) and many (all?) will work out from your course / speed and their if you are likely to collide and warn you. As you're on a budget you are unlikely to be transmitting AIS data yourself. On the more sophisticated systems you can presumably select and AIS target on screen and ask the plotter/vhf to call that vessel directly.

[BogMonster]

Thanks - I know roughly what ships around here transmit AIS as my other half has a PC-based AIS receiver system in the office - part of her job. I'm not worried about transmitting my own position, I really just wondered whether a DSC-enabled VHF linked to a chartplotter would show large ships who were actively transmitting an AIS position, but I guess not by the sound of it?

[willk]

Originally Posted by BogMonster

I really just wondered whether a DSC-enabled VHF linked to a chartplotter would show large ships who were actively transmitting an AIS position, but I guess not by the sound of it?

No, you'd need a VHF with an AIS receiver in it (extra £100)

Or a plotter with an AIS receiver in it.

Or a stand-alone AIS receiver black box linked to your plotter.

[BogMonster]

Thanks - thought that was probably the case. The only two Icoms with AIS look like big whizzy ones so they are out.

Looking at this Standard Horizon GX2100

http://www.standardhorizon.com/index...3&isArchived=0

This says it has "38400 AIS VDM sentence output to compatible GPS Chart Plotter" and then elsewhere in the spec it mentions NMEA but not specifically in relation to AIS output - would it work with the Garmin 551s? I have also looked at the manual for the GX2100 but it appears to use one set of NMEA wires for regular communication and a different wire for AIS signal so I'm not clear if this is "normal" NMEA or not ... anybody know? I thought NMEA was only two wires but I don't know much about it

If the two will work together it would provide chart, AIS, DSC VHF and sonar which is not a bad combination out of two boxes and one external antenna

[Channel Ribs]

You have two sets of NMEA connections, one fast and one slow. The fast provides the AIS data and the slow is a two-way feed for DSC stuff.