Need a NMEA Guru

[Tugw]

Anybody know how to get a Nasa Heading sensor to work with a JRC 1000 Radar? Apparently they dont talk the same gibberish.

I was going to shoot both of them but i thought id ask here before loading the shotgun.


Thanks

 

[Chris_d]

Well assuming they are both running NMEA Canbuses the usual problem is one has the Baud rate set wrong, older stuff ran much slower set them all to 9600.

 

[PaulGooch]

NMEA 0183 baud rate is 4800, apart from AIS, which is 38400. I doubt the NASA or JVC have any options to change that.

The compass outputs the HDG sentance, which the JVC "listens" for, so no reason for them not to work together. I believe the NASA sensor has three wires, red and black for power, plus a blue data wire. Connect the blue data wire to the yellow wire on the JVC. The JVC green wire is the input data ground, as there is no data ground on the NASA the normal procedure is to connect this wire to 12v negative.

I also believe the NASA has a gimbal locking pin that needs to be removed for it to work.

Worth noting that the NASA sensor is too slow for reliable MARPA tracking, as it's only 1hz.

 

[Hurricane]

Also remember

NMEA 0183 is a simple serial interface.
To this end you can "parallel" up to 4 receivers (listeners) onto a single transmitter (talker) but there must be only one transmitter (talker) on any particular connection.

In my experience, this is usually the problem.

So, in your case, the Nasa Heading Sensor must be the only transmitter (talker) on the connection into the JRC Radar's input.

 

[PaulGooch]

Also remember

NMEA 0183 is a simple serial interface.
To this end you can "parallel" up to 4 receivers (listeners) onto a single transmitter (talker) but there must be only one transmitter (talker) on any particular connection.

In my experience, this is usually the problem.

So, in your case, the Nasa Heading Sensor must be the only transmitter (talker) on the connection into the JRC Radar's input.

Good point. In which case, it might be better for the OP to connect the heading sensor to his plotter, then plotter out to the radar. That way, the plotter gets a more accurate heading (particularly useful at very slow speeds) and the radar gets heading and position data.

 

[Tugw]

Thank you Gents, Ill give it a whizz.

Shotgun is back in the cupboard for now