Maritime decoding, NAVTEX, GMDSS etc

[Reece]

Back in the old days I used to monitor NAVTEX transmissions and the reports from stations like NRV/NMC were very interesting, you could manually plot/mark these on a map, I really liked this!
It seems that these reports are rare/thinning out nowadays and now use GMDSS, the problem is there is virtually no info that is of any use, almost no lat/long info to plot, unlike HFDL for aircraft.
Is there any other transmissions that give lat/long info on ships at sea including distress calls?
Anyone know anything about DSC?

 

[ka3jjz]

As this crosses over into the VHF marine world, I've moved the question...

AIS signals will give ship positions - in fact, it's become so prevalent that an experiment on the ISS took place last year to see if a satellite could improve coverage along coastlines where there may be dead spots.

And as for DSC - well these 2 links will do the job, I think

AIS - The RadioReference Wiki

DSCdecoder

I'm fairly certain that a discriminator tapped scanner would be needed for AIS - I know the experiment on the ISS used a tap off their Kenwood radio (many ham radios have a '9600 baud output' which is, in fact, pretty close to a tap...) to drive their experiment.

By the way, the experiment went well. They got so much traffic that it's clear they would need some additional filtering and selection criteria to be applied to the software to avoid overloading the message buffers.

HTH...Mike

 

[Reece]

Thanks Mike, that's worth investigating!!
AIS seems to be dead here in Australia!