Cheap Chinese AIS Transponder

[BrianH]

I am looking at the specs for my GX2100. It does not say if it monitors both channels. Any way to tell? I notice it often gets the MMSI of a ship (with a class A transponder) before it gets its name. Is that normal?

Yes, the target data is in two sets, dynamic and static. Dynamic with MMSI and all the positional information is repeated within seconds, depending on speed, while the static data, also with MMSI for matching, with the ship name is sent only ever 6 minutes. It is one reason why I want to replace my original receiver which, common to most at the time, is two channel but single receiver that switches between the two frequencies. It can get out of synchronisation by missing one transmission and having to wait another six minutes for the next .. and if it misses that because again it was on the other, non-listening channel ...

Sometimes I had to wait up to 20 minutes before a target's static data was filled in. Manufacturers can be very cagey about whether their receiver is genuinely two-channel, parallel, simultaneous reception, quoting only two-channel - NASA were noted for that. However, nearly all modern units are simultaneous, dual-channel receivers now ... although often price is the final decider.

 

[pvb]

2) In very crowded waterways like the Solent it may be prudent in clear conditions in the daylight to turn off your AIS transmissions. On the other hand it has been suggested that if filtering was better on AIS display software this would not be necessary. It is not an issue with the AIS bandwidth just with clutter.

Bandwidth of course isn't an issue, but AIS does have a finite number of available time slots for transmission. Priority is always given to Class A units, and Class B units are allowed to pick up spare time slots. In somewhere like the Solent, if lots of yachts have Class B transponders operating, it's feasible for the Class B performance to degrade significantly. It won't worry the ships, because Class A will still work, and generally they'll switch off Class B, but it could frustrate a lot of yachties.

 

[AngusMcDoon]

Some people do seem to be forgetting that AIS is a standard used around the world and that while CE marking is undoubtedly helpful, it is not a necessary condition for adequate quality. Neither is price.

Are you implying that I don't realise that AIS is a standard, because if so, you are incorrect? However, just because a manufacturer has implemented the AIS standard does not mean that the device is safe to use. For example, they may have used cheap sub-standard components in the analogue transmission side that might allow the transmission frequency to drift on a hot day with the consequence that it could splat noise all over channel 16 denying VHF comms to thousands of others. Proper testing will identify this type of fault, because the transmission frequency will have been measured across a wide range of environmental conditions. I don't know what your profession is, but I suspect that the testing that takes place before a certificate is issued is considerably more exhaustive than you realize.

 

[AngusMcDoon]

a Chinese made AIS system might possibly work perfectly well in Chinese waters without the Magic Stamp.

And there are the 2 important words. Yes, possibly it might, but unless it has a CE mark (which this product has) and you can verify that it is genuine (which as a personal importer is not straightforward), you just don't know.

 

[pvb]

Are you implying that I don't realise that AIS is a standard, because if so, you are incorrect? However, just because a manufacturer has implemented the AIS standard does not mean that the device is safe to use. For example, they may have used cheap sub-standard components in the analogue transmission side that might allow the transmission frequency to drift on a hot day with the consequence that it could splat noise all over channel 16 denying VHF comms to thousands of others. Proper testing will identify this type of fault, because the transmission frequency will have been measured across a wide range of environmental conditions. I don't know what your profession is, but I suspect that the testing that takes place before a certificate is issued is considerably more exhaustive than you realize.

CE marking is somewhat farcical, because the authorities are quite happy for non-CE marked equipment to be used on visiting vessels. One of my handhelds isn't CE marked; I bought it years ago on eBay fron Hong Kong because it was tiny, had a DSC emergency button, and also received entertainment radio. It hasn't denied VHF comms to thousands of others, though.

 

[JumbleDuck]

Are you implying that I don't realise that AIS is a standard, because if so, you are incorrect? However, just because a manufacturer has implemented the AIS standard does not mean that the device is safe to use. For example, they may have used cheap sub-standard components in the analogue transmission side that might allow the transmission frequency to drift on a hot day with the consequence that it could splat noise all over channel 16 denying VHF comms to thousands of others. Proper testing will identify this type of fault, because the transmission frequency will have been measured across a wide range of environmental conditions. I don't know what your profession is, but I suspect that the testing that takes place before a certificate is issued is considerably more exhaustive than you realize.

I am quite sure you are aware of all the issues. My point is that when a protocol or standard applies worldwide, there is not necessarily much practical point in having multiple certification; if this unit is safe and effective in Chinese waters it will also be safe and effective here, off Sri Lanka or around Hawaii. If, has been suggested, it is widely sold in China, I would have expected any shortcomings to have been picked up there.

It's different when local standards are involved. For European systems it clearly makes sense to have European certification, but just as boats without RCD compliance float around quite happily all over the world, so non-CE electronic equipment can be perfectly good.

 

[AngusMcDoon]

CE marking is somewhat farcical, because the authorities are quite happy for non-CE marked equipment to be used on visiting vessels.

That, I agree, is a weakness and unless the IMO were to implement world wide conformance testing, I don't see a solution. There is a similar issue in aviation but it seems operators of sub-standard aircraft are just banned from entering our airspace.

 

[JumbleDuck]

And there are the 2 important words. Yes, possibly it might, but unless it has a CE mark (which this product has) and you can verify that it is genuine (which as a personal importer is not straightforward), you just don't know.

It's perhaps a little Eurocentric to suggest that only a CE mark can possibly guarantee standards compliance. Aren't the Americans capable of testing AIS systems, for example?

 

[AngusMcDoon]

It's perhaps a little Eurocentric to suggest that only a CE mark can possibly guarantee standards compliance. Aren't the Americans capable of testing AIS systems, for example?

Once again, I didn't say that, and yes, of course they are. However, like it or not, we are in the EU for now and CE marking is our conformance regime. The OP has imported one into the EU, not the USA. You may not realize it, and you may not like the considerable costs it incurs on low volume products like marine electronics, but conformance testing and approval has brought huge benefits to everyday mundane products like mobile phones.

 

[JumbleDuck]

Once again, I didn't say that,

"unless it has a CE mark (which this product has) and you can verify that it is genuine (which as a personal importer is not straightforward), you just don't know"

which, you'll remember, applied to my suggestion that they might work fine in Chinese waters.

However, like it or not, we are in the EU for now and CE marking is our conformance regime. The OP has imported one into the EU, not the USA. You may not realize it, and you may not like the considerable costs it incurs on low volume products like marine electronics, but conformance testing and approval has brought huge benefits to everyday mundane products like mobile phones.

Agreed completely. Anyone buying untested equipment is taking a big risk. But for global standards, I really, really don't think it matters, practically speaking, where the testing is done. Would you reject a piece of equipment because it was made to DIN standards and not BS?

 

[ianabc]

$401 US for a 12 volt AIS transponder


plus Paypal fee of 16 and shipping

hard to beat on price and featuresMatsutec


"HP-33A 4.3” AIS transponder combo GPS navigator.

Best price of HP-33A AIS transponder combo GPS navigator is us$320.
Shipping cost to Canada is us$65 by DHL.
Paypal fee: us$16
Total amount: us$401"

 

[JumbleDuck]

$401 US for a 12 volt AIS transponder

Yeah, but what does the FCC know about testing and certifying electronics?

 

[Neeves]

This is almost like an anchor thread.

Whatever ones views on the specific item of equipment the problem is going to be increasingly common. 'China' is going to be a cheap source of marine electronics.

They have a huge marine industry, many of the vessels in their local waters are small and they are going to need the same sort of equipment we need.

Given that (I think) the availability of cheap equipment will increase it would be a great service if someone were able to define the route to determining if a said 'Certificate of Conformity' was valid - otherwise the debate over conformability will be repeated again and again. Surely checking a certificate is relatively easy. If the equipment does conform the debate can then focus on the equipment and its pros and cons.

Jonathan

 

[BruceDanforth]

It isn't about the product meeting the global standards associated with AIS or whether it 'works fine'. It is about conformance. Some details of the type of stuff here:

http://www.cclab.com/ce-testing.htm

"unless it has a CE mark (which this product has) and you can verify that it is genuine (which as a personal importer is not straightforward), you just don't know"

which, you'll remember, applied to my suggestion that they might work fine in Chinese waters.



Agreed completely. Anyone buying untested equipment is taking a big risk. But for global standards, I really, really don't think it matters, practically speaking, where the testing is done. Would you reject a piece of equipment because it was made to DIN standards and not BS?

 

[JumbleDuck]

It isn't about the product meeting the global standards associated with AIS or whether it 'works fine'. It is about conformance.

And how much trouble is someone likely to get into who uses an AIS system which meets the standards and works well? Is there chaos every time a non-EU ship enters the Solent with its AIS switched on?

 

[Bi111ion]

$401 US for a 12 volt AIS transponder

Unfortunately we would have similar costs importing from the US as we have from China, making it more expensive here. Actually I didn't check the price for the AIS transceiver only (rather than the combined GPS/AIS display unit).

 

[BruceDanforth]

Flag your boat in some third world administration and put whatever **** on it you like.

You've been told about the conformance regime for bringing goods into the EU ad-nauseum by people more eloquent than me and I've lost the will to argue with your straw men.

And how much trouble is someone likely to get into who uses an AIS system which meets the standards and works well? Is there chaos every time a non-EU ship enters the Solent with its AIS switched on?

 

[Bi111ion]

Flag your boat in some third world administration and put whatever **** on it you like.

You've been told about the conformance regime for bringing goods into the EU ad-nauseum by people more eloquent than me and I've lost the will to argue with your straw men.

I don't use this forum very much but I am not sure what is going on. It has been determined that the unit in question is CE marked. Why are people still arguing about importing non-compliant ones? Is there someone selling even cheaper AIS transceivers that are not CE marked? Are people just reading some of the posts and reacting to them with out reading the thread. I have heard it said that the internet is mainly for arguing with strangers but this seems to be taking it to extremes.

 

[BruceDanforth]

It has been determined someone has screen printed 'CE' on it.

I don't use this forum very much but I am not sure what is going on. It has been determined that the unit in question is CE marked. Why are people still arguing about importing non-compliant ones? Is there someone selling even cheaper AIS transceivers that are not CE marked? Are people just reading some of the posts and reacting to them with out reading the thread. I have heard it said that the internet is mainly for arguing with strangers but this seems to be taking it to extremes.

 

[Rigger Mortice]

I don't use this forum very much but I am not sure what is going on. It has been determined that the unit in question is CE marked. Why are people still arguing about importing non-compliant ones? Is there someone selling even cheaper AIS transceivers that are not CE marked? Are people just reading some of the posts and reacting to them with out reading the thread. I have heard it said that the internet is mainly for arguing with strangers but this seems to be taking it to extremes.

Just wait till you post about something controversial!
In the meanwhile, thanks for letting us know about this unit and do post about how it performs when you've tried it out. I for one will be thinking about putting one on my shopping list.