By Russ, on August 24th, 2009
I applaud Raymarine for having brought this unit out earlier this year, it is good product marketing and market positioning (pun intended:-)
But if you already have a reasonably sophisticated set up, and already have AIS, is it worth spending £800+ to upgrade to this unit?
Here is my take on the list of features for the AIS500:
| Feature |
Comment |
| * Class B AIS Receive & Transmit |
Good – and so do all the competition at this level |
| * Dual Channel AIS Monitoring Ability |
Good – and so do all the competition at this level |
| * Targets displayed on chart and radar screens |
Clever – but I normally overlay radar on the chart plotter or display AIS targets on the chart rather than the radar which could be very confusing if not misleading due to the different methods of target acquisition |
|
* LED Status Indicator
|
Good – Surprising omission on so many marine electronics and very annoying when there is no status light and you are troubleshooting.
See my posting here on the RaymarineAIS250 |
| * NMEA 0183 – Compatibility with Raymarine A, C, E and G Series |
Good – the great majority of Raymarine users must be on C series (or lower) still. |
| * Buddy Tracking via Raymarine MFD – Distinguish favourite targets (MMSIs) from others by adding to favourite list |
Clever – but is this really needed – oh ok could stave off boredom in some situations to switch between “favourites” and “all” targets. In between calling your buddy on the radio… |
| * Silent Mode – Turn off transmit function during tournaments or races if you do not wish to be seen. |
Good – But only if you expect to be sailing in regions where piracy is possible – not really a problem in the Solent – yet!
I did refer to this as a good thing in my posting here:-) |
| |
|
| * Built-in NMEA multiplexor |
Not Good – I have a principle of using separate dedicated pieces of electronics instead of multifunction devices ion this situation. A faulty multiplexor can take down the whole backbone and all links between devices I would not want to troubleshoot that with a device that was doping so much else as well.
See my posting here on multiplexors. |
| * VHF Splitter – No need to buy a separate antenna. Utilize your existing VHF antenna and cable. |
Not good – don’t use splitters on your VHF cable!. keep the radio and its aerial as separate as possible. Yes I know that DSC has meant connecting the VHF to the NMEA circuit – but just don’t mess with the VHF aerial. This is a critical lifeline. Install a separate VHF aerial for AIS on the pushpit IMHO. |
| * Includes dedicated external GPS antenna (16 channels) |
Not good – as per comment above. Keep the GPS separate, you probably already have one, get another one for backup don’t get one built in to another multifunction device. |
|
* Configure via PC Software
* Software upgradeable through PC and RS232
|
Ok – but why use serial connections and then very probably a serial to USB convertor when you can use high speed USB. Most modern laptops don’t even have serial ports
See my posting here on serial / USB convertors |
I last did a quick survey of transponders (or are they transceivers) in June 2008, but I have held off updating this since I believe that we can expect another revolution in AIS for small boats in the next 6 months.
On that basis I would not buy the AIS500 now, if you already have AIS – if you don?t – then it is a very capable unit with the benefit of a back up GPS.
If you already have AIS and you want to spend £800 buy Raymarine shares, if you made 30% profit when Garmin buy them, that would be an extra £240 to spend on the next generation AIS – then again shares can go down as well as up:-)
By Russ, on May 18th, 2009
A bit late in the day I have been researching replacements for my Class B 121.5Mhz EPIRB which will be relegated to the grab bag and used as a PLB (Personal Locator Beacon) in an emergency. Cospas-Sarsat ceased satellite processing of 121.5/243 MHz beacons 1 February 2009. These beacons will only be able to be detected by ground-based receivers and aircraft for example actually engaged in a SAR operation that had been initiated using the new systems.
A bit of internet research reminded me that the old analog system was accurate to around 20km (10.8nm) and that a SAR (search and rescue) operation would only be launched after two satellite passes – which could mean a delay of about 2 to 3 hours, often it would take 6 hrs to resolve the location by using multiple passes of the weather satellites system. The other factor to note is that the old 121.5Mhz system transmitted using about 75-100 milliwatts of power as opposed to the new beacons that are using 5 watts of power – a stronger transmission is a good thing in bad weather or storm conditions or when your location may be obstructed by things like cliffs!
Satellites receiving the old analog 121.5Mhz and the new digital 406Mhz systems still use doplar shift techniques to try and resolve the location of the beacon. But the new system is accurate to about 5km (2.6nm) as opposed to the old 20km (10.8nm). The old analog system only transmits a tone so the SAR operation cannot determine what is going on until they locate the beacon and find out that it isn’t a false alarm or some errant piece of electronics like a set top box on TV! The new system transmits actual data digitally which can then be linked automatically to your registration data bringing up who to phone and details of your vessel and so on. In the UK you must register your 406Mhz beacon with the MCA
Is added GPS a useful feature?
If the unit you buy has the added facility to transmit GPS location data as well then the accuracy is even greater – about +/-125m. It isn’t as accurate as your chartplotter GPS simply 
because the transmission of the GPS data is limited by the message length of the protocol being used. Even if your beacon is destroyed in the emergency it only needs to transmit for a few minutes for the satellites to pick it up and resolve the location. Pretty damn good I think:-)
The main satellite system for picking the beacon’s signal is the SARSAT system, but in addition the geostationary GEOSAR satellites that cover more than 80% of the earths surface also pick up signals and can relay the GPS location data even though they cannot compute location themselves using the doplar effect.
So how do you choose a 406Mhx beacon for your boat?
The choice is then between Category I (auto deployment) and Category II (manual deployment) 406Mhz beacons…and also units with or without GPS.
I have prepared a small table of units available in the UK market below. Click on the images for a larger view.
Clearly I think you should get one with built in GPS, and if you can get a 16 channel GPS all the better. I dont think the CatI auto deployment is worth the extra money…
By Russ, on December 17th, 2008
I have long lamented the poor service that boaters whether power or 
sail get when installing electronics on their vessels. Getting someone that understands a good installation, is honest enough to read the manual before starting, and doesn’t rip you off with unexpected “extras” is as rare as getting a good plumber or an honest politician.
I have recently been looking at the The British Marine Electronics Association web site and noticed that they do more than represent the trade. The obviously are a trade organisations that represents installers and manufacturers of electrical and electronic equipment for marine use.
But they do have a “Code of Practice for Electrical and Electronic Installations in Small Craft”. This code is produced by the BMEA as a guide to how installations should meet the Standards required for compliance with the Recreational Craft Directive (RCD). It is based on the ISO Standards for AC & DC installations. The Code of Practice is available to all including trade and DIY installers alike and can be obtained through the BMF technical department (phone 01784 223634 or email: cabel@britishmarine.co.uk)
They also run an accreditation scheme called BMET. British Marine Electronics Technician accreditation is a new scheme that has been introduced to recognise the qualifications and experience of those involved with the installation of electronic and electrical equipment in boats.The scheme consists of intermediate and advanced level examinations and, verification of a candidate’s practical competence.
One can but hope that by choosing a company with staff that have attained BMET accreditation …”you can be confident that you will get the highest standards of workmanship and expertise …”
hmmm…is this like the logos that builders put on the back of their vans – or is it a real qualification?….I would love to know…
By Russ, on September 20th, 2008
Bilge pumps are like flares… you never need them until you REALLY need them, and when you do, you will wish you had 2 fitted!
The recent test of bilge pumps carried out by Profs. at Southampton Solent University for Practical Boat Owner has a few gems in it. I didn’t realise for instance that the recommended discharge point is at the stern just like the engine exhaust. The discharge pipe has to be as short as possible because the energy required to overcome friction can exceed the energy required to lift the water!.
Most of the pumps tested were 12v, manual switched, and under £50. The most impressive were the Attwood Tsunami and the Vetus EBP 80 . Both capable of lifting 40 litres (10 gals) of water 1 metre in 1 minute, and a good flow rate for power consumed.
Due to lift height / friction loss in outlet hoses, bilge pumps are only running at (estimate) 80% of their stated capacity. So a 1200 gph bilge pump, is in the real world only giving you 960 gph.
A wave that swamps the cockpit can easily dump 500 litres (132 gals) of water in the boat in one hit. I realise that that does not mean that the water goes into the bilge -it should drain out of your cockpit drains. But, just imagine for arguments sake that the water all goes below. The Attwood Tsunami rated at 1200gph (4,542 lph) running at full capacity would take 6.6 minutes to pump this out. If you say that friction losses cause by the length of pipe reduce efficiency to 80% then the time to pump 500 litres would be more like 8 minutes.
Of course if the water was from wave then at least you have the inter wave delay to pump water out – if the water was coming from a leak in the hull then there would be no respite to the water ingress and the pump may be fighting a losing battle, Nevertheless it would, in theory, buy you a few extra minutes to find the right sized bung!
I think I would rather blow the budget of £50 and fit a higher capacity pump such as the Johnson 2200 gph pump.
By Russ, on September 14th, 2008
Just like the PowerMonkey that I reviewed and have used on my boat, for the past year, the FreeLoader is a power pack that can itself be charged using a solar panel.
Freeloader is a portable charging system that can power any hand held device anywhere, anytime. Freeloader takes power from its solar panels, the supplied Supercharger or via its charge cable that plugs into a computers’ USB. Once charged, 
Freeloader’s internal battery can power an iPod for 18hours, a mobile phone for 44 hours, PSP for 2.5 hours or a PDA for 22 hours.
I can verify the the Powermonkey works fine having used it since August 2007. But it looks like this company have a number of other products in the portable solar device market. See the Solar Technology website – they even make solar toys like helicopters!
Its good to see so many alternative energy products coming on to the market now. It will mean that they will get more and more powerful and efficient – and maybe one day all this product development will result in real hybrid or even totally solar powered boats. I will be posting on that subject soon.
If your are wondering how to workout what size of solar panel to buy for a specific purpose on your boat there is a simple calculator and explanation on the Solar Technology web site.
I applaud Raymarine for having brought this unit out earlier this year, it is good product marketing and market positioning (pun intended:-)
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