Garmin 276 NMEA output to NASA SX 35 VHF

[Captain Haddock]

Chaps,

I wonder if someone can help. I fitted a NASA SX 35 VHF to my boat today and could not get the Garmin 276 GPS to pass it's NMEA info to the VHF.

Here's what I've done:-

1) Established the radio was recieving power and was working.
2) Connected the Blue Garmin NMEA+ wire to the Brown NASA wire.
3) Connected the Black Garmin Negative wire to the NASA Red wire.
4) Configured the GPS COM1 to talk NMEA IN/NMEA OUT @ 4800
5) Set the NASA SX 35 to recieve NMEA data.

With that lot I should be good to go!... not so.

There are a couple of factors that may be causing the problem.

As I was in a boat shed, in my boat I could not acquire a satelite signal, would that mean that because I couldn't acquire a sat link the NASA would still display 999,99,99N, 999,99,99W?

Because of the lack of signal I thought I'd run the GPS in simulation mode, it didn't work. Does simulated mode transmit the simulated data to any NMEA connected device?

And finally...

My boat batteries are seriously low on power, even though I can fire up the radio and the GPS I reckon they are 20% full (The shed has meant no solar top ups). As a result the 276 GPS has an inbuilt battery that lasts for 15 hours, this is fully charged. Could low yacht battery power to the radio be a contributing factor to the NMEA data not being transmitted?

I hope someone can help as this has me baffled, as I'm sure it's wired up right.

 

[KREW2]

Hi
Why don't you phone NASA I found them very helpful.I also think the GPS negative goes to earth, I'm sure someone will correct me if I'm wrong.

 

[Captain Haddock]

Hi!

I've not tried calling as I know I'll be caught in the corporate punter in the middle game, NASA say after 20 mins of mock diagnosis "It's not us try Garmin", Garmin say after 5 mins of mock diagnosis "It's not us try NASA" /forums/images/graemlins/crazy.gif

I was hoping someone out there may actually have a Garmin - NASA installation and could relay their experience.

I was seriously beggining to doubt whether it even works!

 

[salamicollie]

I've got an Sx35 and Garmin 152 - you sound like you have connected it all up OK -if Garmin is firing up you have also got garmin Black to -ve so that's correct- at least done same as I have and mine works. Pretty sure that no GPS lock means that there is no info in the RMC sentence and therefore Sx35 is showing all nines.

Can't comment on simulate mode as have never used it!

Looks like you need to get out the shed to test it....

Sorry can't be any more help

 

[crossbones]

Nasa aren't the kind of people to palm you off. Your connections sound ok. The blue wire from the garmin is nmea output and goes to the brown wire on the sx35. As the garmin signal is reference to negative then the red wire from the garmin goes to supply negative. The sx35 needs the RMC sentence and the garmin needs to be set nmea to nmea. The garmin should send out nmea when in simulate mode but check it really is in this mode and you haven't missed a key press. Low battery is not likely to be a problem as on light load there should still be enough volts to operate.
Finally the sx35 can be used in a manual mode where lat and long are entered manually so check that it is set to manual off.

 

[Captain Haddock]

UPDATE: Garmin 276 NMEA output to NASA SX 35 VHF

UPDATE: I now finally have this going. /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

I noticed that the wire that the NASA uses is thinner than a knats hair so I extended the wire by using some decent stuff so I could ensure a proper connection with the knats hair wire and the rest of my system.

I also connected the negative to the ships main negative run whilst I was at it instead of connecting it to the GPS negative.

I switched on the power and it all fired up and Lat and Long appeared on my NASA immediately

Many thanks for everyones help and suggestions.