Recommendations for AIS Transponder

[Mr Cassandra]

Would this be a simple plug in to an Raymarine Axiom Pro.
I have absolutely no technical ability understanding all the jargon about various ,similar to me products.

The reason i offer this one as there not the ones recommended on Amazon de .

 

[pvb]

Would this be a simple plug in to an Raymarine Axiom Pro.
I have absolutely no technical ability understanding all the jargon about various ,similar to me products.

The reason i offer this one as there not the ones recommended on Amazon de .

Yes, with NMEA2000 it's just plug'n'play. No fiddly wiring involved.

 

[TopBanana]

Thanks chaps, just saved me a packet as I was all set to go with Simrad

 

[Mr Cassandra]

Yes, with NMEA2000 it's just plug'n'play. No fiddly wiring involved.

Apologies this type Matsutec HA-102 Marine AIS Receiver and Transmitter System Class B AIS Transponder Dual Channel Function Cstdma Function

 

[PaulRainbow]

Yes, with NMEA2000 it's just plug'n'play. No fiddly wiring involved.

The Matsutec doesn't look as though it has NMEA2000, only NMEA 0183 and the Axiom does not support 0183

 

[pvb]

The Matsutec doesn't look as though it has NMEA2000, only NMEA 0183 and the Axiom does not support 0183

That's correct, but rtboss1 didn't mention Matsutec. I assumed he meant em-trak.

 

[pvb]

Apologies this type Matsutec HA-102 Marine AIS Receiver and Transmitter System Class B AIS Transponder Dual Channel Function Cstdma Function

No, it won't work with Axiom Pro. And I wouldn't recommend it anyway; customer service is dire according to reports.

 

[Boathacker]

Last year or so there was a significant change to the class B transceiver to improve operation. The permitted power has been increased to 5W and the protocol changed to SOTDMA from CSTDMA.
As I understand it the SOTDMA device claims a transmission slot and reserves it for itself regardless of any other vessels, this is the same as Class A AIS found on large commercial vessels. In contrast CSTDMA only listens for a quiet slot and then attempts a transmission.

The number of time slots is very large so I do not know why the change has been made unless they are concerned that the carrier sense only system was causing too many transmit collisions as the use of class B is increased at sailing events like the round the Island Race and hence making the system inefficient.

I wondered if the new class B+ will start to crowd out class B as they reserve five or more time slots in advance.
I am surprised there is not much knowledge of this change - it seems to be a simple software update that really costs nothing.

My question is why would you not choose SOTDMA as it only 20% more expensive (see the em-track 900 range for example ) and it should work better in the future?

 

[PaulRainbow]

Last year or so there was a significant change to the class B transceiver to improve operation. The permitted power has been increased to 5W and the protocol changed to SOTDMA from CSTDMA.
As I understand it the SOTDMA device claims a transmission slot and reserves it for itself regardless of any other vessels, this is the same as Class A AIS found on large commercial vessels. In contrast CSTDMA only listens for a quiet slot and then attempts a transmission.

The number of time slots is very large so I do not know why the change has been made unless they are concerned that the carrier sense only system was causing too many transmit collisions as the use of class B is increased at sailing events like the round the Island Race and hence making the system inefficient.

I wondered if the new class B+ will start to crowd out class B as they reserve five or more time slots in advance.
I am surprised there is not much knowledge of this change - it seems to be a simple software update that really costs nothing.

My question is why would you not choose SOTDMA as it only 20% more expensive (see the em-track 900 range for example ) and it should work better in the future?

It's true that the time slots are reserved in the same way as class A AIS, but unless you are travelling at speed that's not going to be a significant thing. Transmission rates with SOTDMA are the same as CSTDMA unless you are travelling at speeds in excess of 14 knots. So very useful for high speed craft, not so much so for slower vessels.

Still worth having, especially with the higher transmit power and not significantly more expensive, as you say.

 

[prv]

That's correct, but rtboss1 didn't mention Matsutec. I assumed he meant em-trak.

For some reason he wrote it in enormous letters in the post before the one in which he asked the question. But since it ended up on the previous page, it was easy to miss.

Pete

 

[Mr Cassandra]

For some reason he wrote it in enormous letters in the post before the one in which he asked the question. But since it ended up on the previous page, it was easy to miss.

Pete

Did I mention i was technically challenged!

Very slow Internet here in lavrio Greece ,all letter and numbers transposed .some9 a simple sentence end up with a number in it for some reason

 

[Boathacker]

Just started programming my em-track 953.
I have discovered that only the new SOTDMA 5W AIS has the long range broadcast to satellite on channel 27 included (I presume this is used used when out of range of shore stations not for just for distress). This is not made clear in the sales literature. You should to bear this in mind if you are about to purchase standard rather than high power AIS transceivers as it seems you will not benefit from this valuable safety feature.
It will be a while before I can test this but there are many dead spots around the coast that have no AIS shore reception.

All this assumes that shore based vessel tracking is an important safety feature to you as this is in addition to ship to ship tracking which is, of course a very useful navigation aid.

Question for forum - Anyone had any experience of ship to satellite AIS tracking and does it really work on small vessels with a standard masthead aerial?