[LW] [LW11] Connect T122 to Digital Yacht AIT3000

[BlueMoon]

I'm trying to connect a TackTick MicroNet system to a Digital Yacht AIT3000 so that:
a) I can pass GPS info from AIT to MicroNet and b) I can pass info from MicroNet (depth, speed, etc) to AIT and onwards to a tablet used as a plotter

First plan was to use an Actisense NGW-1 to bridge between the T122 and N2K backbone using the NMEA-1/GPS input and NMEA-2 output on the T122. I am not seeing Lat/Long appear on the MicroNet display so assume the GPS signal isn't getting through. Could be that the Actisense isn't transmitting at the right Baud rate - it is set to the default 4800 baud. I have no sensors on the MicroNet at the moment so don't know if the output works or not.

I tried moving the Actisense output to the T122's NMEA-2 input, thinking the baud rate might be compatible. That didn't work.

I also tried connecting the fast NMEA0183 output from the AIT3000 to the T122's GPS input. Again no joy.

In all cases my voltmeter says there is a signal at the T122's input. The health check on the TackTick display says that the T122 is connected OK.

So I have 4 questions:
a) what baud rate are the three NMEA ports on the T122 configured for?
b) what NMEA0183 sentences does the T122 expect for GPS? AIT is sending GLL, GGA and RMC I think
c) if the T122 receives valid GPS sentences should I expect the MicroNet display to show Lat/Long and maybe date/time?
d) does anyone know for sure if an AIT3000 will work with a T122?

[Louise - Raymarine - Moderator]

Dear BlueMoon,

Thank you for your post.

So I have 4 questions:
a) what baud rate are the three NMEA ports on the T122 configured for?
a1)4800 baud rate

b) what NMEA0183 sentences does the T122 expect for GPS? AIT is sending GLL, GGA and RMC I think
b) the T122 will receive RMC

c) if the T122 receives valid GPS sentences should I expect the MicroNet display to show Lat/Long and maybe date/time?
c) as long as the micronet system is networked and healthy, you should see the time, date and fix from the GPS

d) does anyone know for sure if an AIT3000 will work with a T122?
d) any NMEA0183 sentences will communicate

These are the sentences for the T122
Received Sentences: DBT, DPT, HDG, HDM, MWV, RMB, RMC, VHW, VLW
Transmitted Sentences: DPT, GLL, HDG, MTW, MWV, RMB, RMC, VHW,
VLW, VWR

The fast output from the AIT3000 to the T122 is in compatible.

You need to connect the pink wire from the AIT3000 to the NMEA 1+ on the T122. You need to connect the violet wire from the AIT3000 to the NMEA 1- on the T122.

Many Thanks
Louise

[BlueMoon]

Thanks for the reply Louise.

If all the NMEA ports on the T122 are set for 4800 baud they should be compatible with the default setting of Actisense NGW-1; and my first plan should have worked.

I know the AIT3000 is getting a good GPS position, so it is getting lost somewhere between the AIT and the MicroNet.

I will try using the AIT's slow NMEA0183 connection as you suggest, but may also need to connect a "sniffer" in a couple of places to track down where the message is failing.

Mike

[BlueMoon]

"You need to connect the pink wire from the AIT3000 to the NMEA 1+ on the T122. You need to connect the violet wire from the AIT3000 to the NMEA 1- on the T122."

That worked a treat, thanks.

[Louise - Raymarine - Moderator]

You are welcome.