What do we think of Smartfind?

[FishyInverness]

So is it a Class A broadcasting at around 18W? How long does the battery last?

[Kannad Safelink R10] Battery lasts 7 years in storage and will operate continuously in broadcast mode for a minimum of 24 hours.

Power is claimed as 2w nominal and Range is claimed as 4 Nautical Miles (typical)

 

[lenseman]

So is it a Class A broadcasting at around 18W? How long does the battery last?

I think you are slightly misunderstanding the differences between an AIS transmitter Class 'A' and an AIS transmitter Class 'B'. Basically they are the same transmitters but the Class 'A' will transmit a greater amount of information, not just an increase in transmitter power.

Agreed that an AIS Class 'A' does transmit at a higher power 7dB higher than Class 'B' (12½ watts compared to 2 watts from Class 'B') but a Class 'A' also sends the vessels Rate of Turn, IMO, Destination more importantly, it transmits every 2 seconds whereas an AIS Class 'B' transmitter sends out a signal every 30 seconds or so.

Just out of interest, when a vessel is at anchor and no change or small changes of GPS, the AIS transmitter goes into 'sleepy mode' and will transmit with a greater time between transmissions, usually once every 3 minutes or so.

So when the new SART MOB/AIS units are talking "Class 'A' " it might have a small increase in transmit power (if you are able to measure it) but the number of transmitted position codes will be increased, it will not necessarily be the full Class 'A' that will be transmitted but will certainly be the 2 second transmit time interval.
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[st599]

Hello Fishy

I think you are slightly misunderstanding the differences between an AIS transmitter Class 'A' and an AIS transmitter Class 'B'. Basically they are the same transmitters but the Class 'A' will transmit a greater amount of information, not just an increase in transmitter power.

Agreed that an AIS Class 'A' does transmit at a higher power 7dB higher than Class 'B' (12½ watts compared to 2 watts from Class 'B') but a Class 'A' also sends the vessels Rate of Turn, IMO, Destination more importantly, it transmits every 2 seconds whereas an AIS Class 'B' transmitter sends out a signal every 30 seconds or so.

Just out of interest, when a vessel is at anchor and no change or small changes of GPS, the AIS transmitter goes into 'sleepy mode' and will transmit with a greater time between transmissions, usually once every 3 minutes or so.

So when the new SART MOB/AIS units are talking "Class 'A' " it might have a small increase in transmit power (if you are able to measure it) but the number of transmitted position codes will be increased, it will not necessarily be the full Class 'A' that will be transmitted but will certainly be the 2 second transmit time interval.
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It also transmits a class a position report rather than a class b.

 

[FishyInverness]

Hello Fishy

Erm, you quoted and replied to (or appeared to) Haydude, but said hello to me?! Was that a typo?

 

[lenseman]

Erm, you quoted and replied to (or appeared to) Haydude, but said hello to me?! Was that a typo?

Yes, apologies

and edited

 

[Chalker]

I've bought the McMurdo AISs for the two of us.
In crowded waters I'm not too concerned, in the middle of an ocean crossing with a missing crew a PLB response would be hours/ days.
Any AIS is likely to be my missing crew. Having up to a 4 mile range would be like magic compared to daylight visibility in big swells, let alone night time.