VHF-DSC-GPS-AIS question.

wigen

wigen

New Member
Joined
13 Sep 2007
Messages
20
Location
Denmark
Visit site
Yesterday I heard from a sales guy in a marine shop that a DSC enabled VHF radio sends AIS info when it's connected to a GPS !!! The VHF/DSC radio acts as a AIS tranciever.

Is the sales guy right ?

Thanks.
 
a DSC enabled VHF radio sends AIS info when it's connected to a GPS !!! The VHF/DSC radio acts as a AIS tranciever.

***************************************************

WHen you press the tit on a DSC radio it transmits a data signal on channel 70 which contains information about the transmitting vessel in a similar manner to that in AIS signals but not the identical information. AIS gives more information about the vessel and its destination where DSC is part of a safety process so contains more information about the emergency , vessel position , time of message and the vessel mmsi number. When making ship to ship calls the DSC data also caries instructions to the listening receiver instructing it what working frequency to go to..
 
What triggered this question was Steve_N that wrote this in the thread "Fitting a VHF with a cockpit command mic.":
"Oh and it also works as a very basic GPS repeater: position, course and speed over ground."
And according to the sales guy the radio should transmit this info every 30 seconds.
 
And according to the sales guy the radio should transmit this info every 30 seconds.

*************************************************

I think he has got this wrong....The GPS sends the data to the radio maybe every 30 seconds...but it is not transmitted by the VHF except as part of a DSC signal...The DSC and AIS data protocols aren t the same and operate on different frequencies.
 
... or is there a manufacturer offering a VHF radio, with built-in DSC and AIS in one box? I've been wondering for a while why no one seems to offer such a product - does the salesman know about a new product?
 
There\'s almost one...

There's the Standard Horizon CPV350, which combines a Class D DSC VHF with a colour GPS chartplotter, which just needs an AIS engine hooking up to it to provide AIS target information. Naturally, not legal for use in the UK.
CPV350_thumb.jpg
 
Most Second Stations mic's repeat the GPS info of the radio on to the second stations screen.
Well I know for sure our's and the Icom's do.

AIS will need another unit, this info can then be displayed onto a chartplotter but not on the VHF.

On your AIS you can display your DSC MMSI number and see that of other vessles, that is about as far as the link with DSC and AIS goes.
 
You must log in or register to reply here.

Share this page

Top