Ocean Hound
New member
Trying to connect up a NASA AIS engine thru to a C120 chartplotter, using VHF Splitter, with no success. Any ideas as to whether it is hard or software problem. Many Thanks
AIS + Raymarine C120
- Thread starter Ocean Hound
- Start date
Dalliance
New member
Is the Baud rate for the NMEA input correct for the AIS? Do you have any other NMEA inputs to the C120?
syfuga
Member
Hi,
The Nasa AIS engine does not come well endowed with documentation, unless things have changed in the last year or so.
I can understand that you might use a VHF splitter to share an aerial between two receivers, but I would be chairy about directly connecting your VHF tx/rx to the input of the AIS. You may land up with a charred AIS engine receive circuit. I share an emergency back up aerial mounted on the gantry at the stern between the AIS and SSB DSC receiver.
All this is unrelated to the output of the AIS engine, which is delivered as a serial interface cable intended for connection to a computer or similar. As I don't have a C120 I cannot comment on how this might match the C120 input interfaces.
However, the AIS engine delivers at 38400 baud, 8 data bits, 1 stop bit, and no parity, if I remember correctly. This is much faster than the standard NMEA interface, which runs at 4800 baud.
If you have a PC notebook handy, use the Windows Hyperterminal utility, having set up the properties of the comms interface to 38400 etc. to establish that you have an output from the AIS engine.
This doesn't directly answer your question, but might have some helpful pointers somewhere.
The Nasa AIS engine does not come well endowed with documentation, unless things have changed in the last year or so.
I can understand that you might use a VHF splitter to share an aerial between two receivers, but I would be chairy about directly connecting your VHF tx/rx to the input of the AIS. You may land up with a charred AIS engine receive circuit. I share an emergency back up aerial mounted on the gantry at the stern between the AIS and SSB DSC receiver.
All this is unrelated to the output of the AIS engine, which is delivered as a serial interface cable intended for connection to a computer or similar. As I don't have a C120 I cannot comment on how this might match the C120 input interfaces.
However, the AIS engine delivers at 38400 baud, 8 data bits, 1 stop bit, and no parity, if I remember correctly. This is much faster than the standard NMEA interface, which runs at 4800 baud.
If you have a PC notebook handy, use the Windows Hyperterminal utility, having set up the properties of the comms interface to 38400 etc. to establish that you have an output from the AIS engine.
This doesn't directly answer your question, but might have some helpful pointers somewhere.
steve6367
Member
Can you tell us what steps you have taken in the setup?
You need to configure the C120 to accept the AIS input...........
You need to configure the C120 to accept the AIS input...........
PembrokeshirePromise
Member
I have this working into a C80.
As others have said - it is dependent upon you not having any other NMEA devices going into the C120 as the NMEA port can be configured for 9600 baud - or for 38400 - which is what is needed for AIS.
Make sure the NMEA port is configured for 38400 baud rate - then its just a case of wiring up the cables (can't remember the colours - but remember the out from the AIS becomes the in on the plotter)
As others have said - if you have a PC its worth checking the AIS box is actually prividing data (I assume there are ships nearby ?)
Some people have also reported issues with the NASA AIS box dropping out from time to time when connected to Raymarine - as it doesn't do true NMEA - works fine on a PC. I think it depends on the tolerance of your units - I've found it normally works OK
Good luck
As others have said - it is dependent upon you not having any other NMEA devices going into the C120 as the NMEA port can be configured for 9600 baud - or for 38400 - which is what is needed for AIS.
Make sure the NMEA port is configured for 38400 baud rate - then its just a case of wiring up the cables (can't remember the colours - but remember the out from the AIS becomes the in on the plotter)
As others have said - if you have a PC its worth checking the AIS box is actually prividing data (I assume there are ships nearby ?)
Some people have also reported issues with the NASA AIS box dropping out from time to time when connected to Raymarine - as it doesn't do true NMEA - works fine on a PC. I think it depends on the tolerance of your units - I've found it normally works OK
Good luck
Ocean Hound
New member
Many thanks guys - boat in the Baltic and going over this W/end so will give all the suggestions a spin.
Edward
Edward
Amphitrite
New member
There have been rumours that the NASA engine does not work with some multiplexers used with the raymarine c-series because of non-standard power levels of the serial output.