Cobra DSC VHF - NASA AIS - Garmin 128 & 126 interface

[Independence]

Up until last year my Cobra VHF radio and NASA AIS were interfaced with my Garmin 128 & 126 GPSs

In an effort to locate the problem I've checked for any obvious loose connections but found nothing so far. Before I go pulling the connections apart to check for anything hidden from view I thought I would check the interface settings on the GPSs

Having consulted the user manual I've no idea which of the following settings I should be adopting:
- Garmin / Garmin (pretty obvious not as the 2 Garmin devices have never been interfaced)
- None / None
- RTCM / None
- RTCM / NMEA
- NMEA / NMEA
- None / NMEA

Is anyone able to confirm?

Thanks

 

[pvb]

Up until last year my Cobra VHF radio and NASA AIS were interfaced with my Garmin 128 & 126 GPSs

Can you perhaps start by explaining exactly what you mean by this?

 

[Independence]

My GPS position no longer appears on my VHF radio or my AIS

 

[pvb]

My GPS position no longer appears on my VHF radio or my AIS

OK, but you said they were interfaced to a Garmin 128 and a Garmin 126. So was the radio connected to one of the GPSs, and the AIS (I'm assuming an "AIS Radar") to the other? Or both connected to one?

 

[Independence]

Both GPSs were independently connected to both the VHF and AIS Radar

I'm assuming 'interfacing' is the correct terminology when describing one piece of electronic equipment sending data to another but I may be wrong!

 

[prv]

Both GPSs were independently connected to both the VHF and AIS Radar

I'm assuming 'interfacing' is the correct terminology when describing one piece of electronic equipment sending data to another but I may be wrong!

You’re not wrong in using that term, but is it one piece of equipment sending data or two? How are both GPSes “independently” connected to both receivers given that the receivers almost certainly don’t have two input ports each?

Pete

 

[MikeCC]

Set the Garmin ports to NMEA/NMEA. 4800 baud if there's a choice.

 

[Independence]

Thanks Mike.

Just for the record I use one GPS at a time and not both together . The appropriate wires from both GPSs are joined to the appropriate wires to the AIS and VHF radio

Probably not explaining that very clearly but it all worked just fine last year

Thanks both again

 

[pvb]

Just for the record I use one GPS at a time and not both together . The appropriate wires from both GPSs are joined to the appropriate wires to the AIS and VHF radio

Probably not explaining that very clearly but it all worked just fine last year

Ah, that makes more sense. You can have one talker connected to two listeners, but not two talkers (as the NMEA data gets garbled).

 

[lpdsn]

Just for the record I use one GPS at a time and not both together . The appropriate wires from both GPSs are joined to the appropriate wires to the AIS and VHF radio

Probably not explaining that very clearly but it all worked just fine last year

A strange set-up but it can work with care. The obvious question is why did they both stop working at once? Did you mess with the settings at the time? In which case resetting them could get it all working again. But if not, there's quite possibly another cause.

If it were me I'd disconnect one transmitter then try to get it all working fine with just one GPS to start with.

 

[Contest1]

OK, but you said they were interfaced to a Garmin 128 and a Garmin 126. So was the radio connected to one of the GPSs, and the AIS (I'm assuming an "AIS Radar") to the other? Or both connected to one?

AIS radar. Is this something new?

 

[pvb]

AIS radar. Is this something new?

Many years ago, Nasa introduced a very crude AIS display device which they called "AIS Radar". They've since changed the name to "AIS SART Plotter", although the unit itself still seems to have "AIS Radar" printed on it. I assumed this was the device the OP had, as it's the only Nasa AIS device which needs a GPS feed into it.

 

[Contest1]

Many years ago, Nasa introduced a very crude AIS display device which they called "AIS Radar". They've since changed the name to "AIS SART Plotter", although the unit itself still seems to have "AIS Radar" printed on it. I assumed this was the device the OP had, as it's the only Nasa AIS device which needs a GPS feed into it.

Thanks PVB. I'd hoped it was the answer to the question of radar v AIS.