Chart plotter, DSC VHF and AIS set up - advice please

MILLPOND

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I want some advice please. I have just purchased a Nauticat and want to set up a digital chart plotter with AIS. I also want to have an AIS transponder so I am visible to shipping. I also need to upgrade my old VHF to a DSC model.

As far as I can work out, I have the following options:
1. To purchase a wireless AIS box (iAIS) which will allow me to buy an iPad and Navionics software, also purchase a separate DSC VHF and AIS transponder
2. To purchase a marine PC with some form of digital chart plotter with AIS overlay taken from a combined AIS/DSC VHF radio and have a separate AIS transponder - but would I need an inverter to supply the computer? Is there a combined DSC+AIS receiver+AIS transponder VHF radio that could be linked to the PC?
3. To buy a marine chart plotter/raymarine device, which seem much more expensive and not as versatile.

The boat is a motor-sailer with a wheel house so there's plenty of room to mount an LCD screen in the dry, and I'm not too worried about power consumption.

Any advice, personal recommendations or tips would be welcome.

Thanks

Henry
 
Keep it simple

Laptop or PC running a chart plotter capable of displaying AIS. Personally I use OpenCPN, which is free, on an old laptop but you will need charts. There are 'free' CM93 vecor charts available on the net but personally I prefer UKHO raster charts (Maptech or Memory Map). OpenCPN still has the best AIS presentation IMHO.

Next you need an AIS transponder which will also receive AIS (you don't need a separate receiver). I have a Digital Yacht AIT2000 which works well and is competitively priced but there are others available. This comes with a separate GPS receiver which can be used to drive the chartplotter and the DSC

Finally you need a DSC radio.

The laptop can be powered by a DC-DC converter - Maplins sell several models.

As a back-up a small tablet with a built in GPS would suffice. I have a Nexus 7 with Memory Map charts which use the same licence as the laptop.

Good luck.
 
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I have just purchased a Nauticat and want to set up a digital chart plotter with AIS. I also want to have an AIS transponder so I am visible to shipping. I also need to upgrade my old VHF to a DSC model.

If you really believe an AIS transponder will ensure your visibility to shipping, you're impossibly optimistic. Spend the money on an active radar reflector instead - that really will make you visible!

Purpose-designed chartplotters do have an advantage; they're very good at what they're designed for. Many of the better ones will also take a radar input and display a radar/chart overlay, surely one of the best innovations of recent years. If you get a combined VHF radio and AIS receiver (Standard Horizon for example), there's also the added benefit that you can call ships directly, without having to re-enter their MMSI number.
 
you don't need a separate receiver

More than that - you don't want a separate receiver, if you have a transmitter. Otherwise (unless it's cleverer than the ones I've seen) your receiver will be constantly screaming that there's another yacht right on top of you.

Pete
 
If you get a combined VHF radio and AIS receiver (Standard Horizon for example), there's also the added benefit that you can call ships directly, without having to re-enter their MMSI number.

In theory this ought to be possible with a separate AIS display or a plotter, too. The display sends an NMEA message to the radio to set up the call. However, for some reason many manufacturers seem to have been rather poor at implementing this (both in displays and in radios) so at present it's probably better to assume that any given combination of display and radio will not allow direct calling a target, until you find a report that says otherwise.

I know for instance that the Vesper Watchmate series works with many Icom radios, but that Standard Horizon radios do not.

Pete
 
If you really believe an AIS transponder will ensure your visibility to shipping, you're impossibly optimistic. Spend the money on an active radar reflector instead - that really will make you visible!

There are other benefits of fitting an AIS transponder apart from the obvious, but rather dubious one I agree, of visibility to other vessels. In order of merit I would list the benefits of a transponder as follows -

1. Vital safety aid - visible to rescue craft.
2. Useful secondary safety aid for relatives and friends to monitor your progress using internet reporting.
3. Useful for fellow boat owners to assist rendezvous.
4. Gives visibility to large vessels, particularly offshore.

Purpose-designed chartplotters do have an advantage; they're very good at what they're designed for. Many of the better ones will also take a radar input and display a radar/chart overlay, surely one of the best innovations of recent years.

From my experience of dedicated chartplotters I would argue that they do not compare well with the best PC based chartplotters. There are obvious benefits of a dedicated chartplotter - waterproof, low power consumption, radar overlay (on the more expensive ones) - none of which are priorities for the OP. However, for the simple task of route planning and real time navigation give me a PC every time. For the record, I have a latest generation Simrad MFD with radar overlay (it came with the boat), similar to the B&G, Lowrance and Navico devices, so my opinion is based on personal use.

If you get a combined VHF radio and AIS receiver (Standard Horizon for example), there's also the added benefit that you can call ships directly, without having to re-enter their MMSI number.

This is a marginal benefit. A separate AIS will identify a dangerous target by name on a screen that can be easily read (unlike a DSC VHF AIS ) and it is a simple matter to call the vessel by name on channel 13 or 16. I have done this several times myself with immediate results.

I believe my recommendations in #2 above best meet the stated requirements of the OP.
 
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From my experience of dedicated chartplotters I would argue that they do not compare well with the best PC based chartplotters. There are obvious benefits of a dedicated chartplotter - waterproof, low power consumption, radar overlay (on the more expensive ones) - none of which are priorities for the OP.

Radar overlay, an incredibly useful feature, is available on the £300 Standard Horizon CP180, hardly a more expensive model! I use a Raymarine C120 radar/plotter, so have no knowledge of PC-based chartplotters - how well does radar overlay work on OpenCPN?
 
Radar overlay, an incredibly useful feature, is available on the £300 Standard Horizon CP180, hardly a more expensive model! I use a Raymarine C120 radar/plotter, so have no knowledge of PC-based chartplotters - how well does radar overlay work on OpenCPN?

I agreed above that radar overlay was one of the benefits of a dedicated chart plotter. However, it was not one of the OPs requirements (at least not stated). Maybe he already has an adequate stand-alone radar?

Regarding OpenCPN, over the last 12 months there has been a development in progress to provide a radar overlay plug-in. I believe it works with the latest Simrad/Lowrance etc. brand of radars but is not fully released. I haven't had the time (or inclination yet) to try it. However, if you are (really) interested (and technically competent to understand such things) you could read up on it here -

http://www.cruisersforum.com/forums/f134/opencpn-radar-overlay-plugin-79081.html.

Let me know your conclusions as I haven't read it all!
 
Regarding OpenCPN, over the last 12 months there has been a development in progress to provide a radar overlay plug-in. I believe it works with the latest Simrad/Lowrance etc. brand of radars but is not fully released. I haven't had the time (or inclination yet) to try it. However, if you are (really) interested (and technically competent to understand such things) you could read up on it here -

http://www.cruisersforum.com/forums/f134/opencpn-radar-overlay-plugin-79081.html.

Let me know your conclusions as I haven't read it all!

I don't have time to read it all, but I gather from your post that radar/chart overlay on a PC isn't easy?
 
I don't have time to read it all, but I gather from your post that radar/chart overlay on a PC isn't easy?

I'd imagine that it's because there isn't a standard way of transmitting radar information. It can't be done using NMEA because that is oriented towards short sentences of data with a slow refresh rate. So, you're into proprietary interfaces and data formats.
 
Laptop or PC running a chart plotter capable of displaying AIS.

Nauticats have beatiful large windows that give great light into the wheel house. Even when waterproofing a laptop or PC is not an issue, being able to see the screen in sunlight probably is...
 
Nauticats have beatiful large windows that give great light into the wheel house. Even when waterproofing a laptop or PC is not an issue, being able to see the screen in sunlight probably is...

If daylight (not really sunlight, with a roof overhead) viewing is a problem there are plenty of daylight (and sunlight) viewable monitors available. Modern flat screen TVs also work quite well as monitors.
 
I don't have time to read it all, but I gather from your post that radar/chart overlay on a PC isn't easy?

I think the reason for the long development process has been resourcing issues rather than technical. Don't forget that OpenCPN has been developed collaboratively by a number of very dedicated programmers (most of whom also sail) but it is voluntary and unpaid work. They have actually done a splendid job to date IMHO and continue to add useful features with each release.

Regarding the radar overlay development, unfortunately, very few of the developers have access to the required radar antenna that is needed for testing (Simrad/Lowrance BR24/3G or 4G) and the couple that do are probably not the best programmers . . .

I think they are also getting into more complex areas of development like MARPA that are not essential for a first release, but the more technical guys are probably enjoying the challenge!

As I understand it, the basic radar display and overlay capability work well in OpenCPN. I expect a working release will be available in the next few months if the required resources and programmers can be brought together.
 
Regarding the radar overlay development, unfortunately, very few of the developers have access to the required radar antenna that is needed for testing (Simrad/Lowrance BR24/3G or 4G) and the couple that do are probably not the best programmers

Sounds like the way for someone to ensure support, then, would be to buy a scanner and lend it to the relevant developers until the feature is done :)

Pete
 
Sounds like the way for someone to ensure support, then, would be to buy a scanner and lend it to the relevant developers until the feature is done :)

Hmmm.... maybe! When commercially available radar/plotters are available relatively cheaply, are waterproof, have low power requirements, are simply plug-and-play, are supported by large organisations, are very easy to use, and work incredibly well, why mess about with laptops and software cobbled together by well-meaning amateurs?
 
Sounds like the way for someone to ensure support, then, would be to buy a scanner and lend it to the relevant developers until the feature is done :)

Pete

Right - but would you be willing at £1,800 a go?

BTW - I think we are into serious thread drift here. Not heard back from the OP yet
 
Hmmm.... maybe! When commercially available radar/plotters are available relatively cheaply, are waterproof, have low power requirements, are simply plug-and-play, are supported by large organisations, are very easy to use, and work incredibly well, why mess about with laptops and software cobbled together by well-meaning amateurs?

. . .because the end result from the well-meaning amateurs is actually better for route planning and real time nav than the (sometimes) over priced items produced by the large organisations (and much more flexible)!
 
. . .because the end result from the well-meaning amateurs is actually better for route planning and real time nav than the (sometimes) over priced items produced by the large organisations (and much more flexible)!

In what way is it better? I have to say my Raymarine plotter is very easy for route planning, and it can display a radar overlay on the chart without difficulty, plus it has decent MARPA. So what's better about the amateur solution?
 
Thank you all for the replies. As Playtime said, the thread seems to be caught in overfalls and is drifting rapidly off course!

I took your suggestion, Playtime, and had a look at OpenCPN which seems like an excellent piece of software. As far as the charts are concerned, I'd probably prefer vector charts so that I can fiddle with the amount of data displayed and de clutter as required. Where can I get the CM93 charts from? I've googled it, and there seem to be some on torrent sites, but it all looks a bit iffy. Are there any above board ways of obtaining them, or can any forum members share the file with me?

I have had a think about hardware and I have an old laptop with a large screen which is quite good in daylight, so will try and resurrect that. Digital Yacht have a device called an AIT2000 class B transponder which also provides GPS position data to a DSC radio. It is 500 quid though. Does anyone know of a cheaper alternative?

I take on board the comment about AIS not being the best method of improving visibility to shipping, so will also look into an active radar reflector. Any recommendations? Incidentally, I do have an old Furuno radar set on board - it's very old fashioned with a green cathode ray tube but it seems to work well. No chance of radar overlay though!
 
In what way is it better? I have to say my Raymarine plotter is very easy for route planning, and it can display a radar overlay on the chart without difficulty, plus it has decent MARPA. So what's better about the amateur solution?

A PC based solution can call on the full facilities of the operating system like file manager, instant internet access with Google Earth overlays and file transfer for sharing routes and waypoints between main and back-up systems.

When route planning the waypoints can be named using a proper keyboard and their properties (name, icon, colour, position etc.) can be instantly changed.

The route can be printed with name, number, bearings/distances, ETA etc. calculated, and the whole route planning process is just much quicker and less 'clunky'. I think few people who have seriously used PC based route planning would argue that a dedicated chart plotter is better (for route planning).

Regarding real time nav the display is on a large screen (and doesn't cost £2,000 plus). Google Earth overlays are available. AIS presentation with adjustable CPA parameters and alarms is the best that I have seen (OpenCPN). Finally on-line logbook with all interesting parameters automatically logged plus free form entries is available.

I could go on . . . .

Maybe you should try it (OpenCPN) for a few weeks - you might be pleasantly surprised!

The major advantage of the dedicated chart plotter is that it can be mounted 'in your face' at the helm. A secondary advantage, as already agreed, is the ability to handle radar overlay. Size for size these benefits come at a high price.
 
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