Connecting AIS receiver to Garmin 750

[eddystone]

I need to connect mcmurdo 15S receiver to my Garmin 750; I don't understand "sentences" or protocols just want to join right wires up; it will be only nmea connection as separate garmin 128 feeds position info to VHF.
Garmin has:
Port 1 tx out
Port 1 rx in
Port 2 tx out
Port 2 rx in
But... mcmurdo has:
Input+ rxp
Input- rxn
Output + txp
Output- txn
Do all 4 ais wires need to be combined with 2 on garmin (implies port 2 is for second device)?; which with which?
Is connecting nmea wires ok with gel connectors?

 

[prv]

To send the AIS data from the receiver to the plotter, you want:

Output + ---> Port 1 rx in
Output - ---> Ground (black power supply wire).

Then make sure that Port 1 is set for 38400bps (high speed) in the Garmin menus.

I don't know what the input to the AIS is for, it may well not be needed. But if you want to wire it up, it will be:

Input + ---> Port 1 tx out
Input - ---> Ground (black power supply wire).

Pete

 

[pvb]

I don't know what the input to the AIS is for, it may well not be needed.

It offers the facility to multiplex another NMEA signal with the AIS output, useful for some plotters which only have one input port.

 

[prv]

It offers the facility to multiplex another NMEA signal with the AIS output, useful for some plotters which only have one input port.

Ta. So not needed for the OP then.

Pete

 

[eddystone]

To send the AIS data from the receiver to the plotter, you want:

Output + ---> Port 1 rx in
Output - ---> Ground (black power supply wire).

Then make sure that Port 1 is set for 38400bps (high speed) in the Garmin menus.

I don't know what the input to the AIS is for, it may well not be needed. But if you want to wire it up, it will be:

Input + ---> Port 1 tx out
Input - ---> Ground (black power supply wire).

Pete

Yesterday was a bit difficult trying to post with my phone (which doesn't show a cut down version of the site) but the Garmin installation instructions say;

a) connect port 1 out (TX) to the in wire (Rx/A+ ) on the NMEA0183 device and the port 1 ( RX) in to the Tx/A+ out on the device
b) the black power ground wire on the Garmin serves as NMEA ground as well and must be attached to the same terminal as the ground on the NMEA device; that works because the mcmurdo instructions also describe the black wire as being a dual power and nmea ground.
I presume "P" means pos and "N" means negative when appended to RX/TX labels?

Does that sound right - it seems now to make sense after looking at the 2 sets of instructions for the nth time.

Couple of other points. I was originally going to route the AISpower red and black wires to the switch panel, but since the black ground has to join up with the Garmin ground to ground the nmea interface, only practical thing to do is stick red positive into same terminal block under chart table where red wire form Garmin goes. Also I have acquired some 3M branded gel connectors - I understand you shouldn't strip the signal wire end to bare - just stick them in and then crimp it with pliers which will break through the insulation and seal the joint - correct?