Garmin 120

[JSP]

My Garmin 120 GPS has been hooked up to my ICOM 411 for a wail now. But for some reason the garmin wont switch on. Only way to get it too switch on is to diconect the NMEA connection to the radio. Once switched on it has changed itself to GARMIN/GARMIN instead of NMEA/NMEA that I had it set too.
Once it's switched on, and the setting changed back, I can then re connect the NMEA wires to the radio and all works fine. Postion and time show up after a few seconds.

Anyone got any ideas?

[JSP]

Anyone?

[geoffs]

The NMEA in to the radio is opto isolated inside the radio, so unless it has a problem the garmin should only see it as an led on the end of the wire.

The garmin on the other hand uses the 0v line as the return for the data.

So check that the data out and the radio have a one to one connection and there are no stray wires.

The garmin is obvioulsy getting loaded badly and is causing it to make a reset to end up with the garmin/garmin data selection.

Also, with the plotter disconnected and radio disconnected from the power, you should have no connection to either the red or black power input to the radio to either of the nmea input wires. Check with meter set to ohms.

[JSP]

Geoffs, your a good man.

This is how I was told to wire up. But I'm starting to doubt there knowledge (noone on here).
Blue NMEA OUT goes to the centre core (+ RED) of the NMEA wire on the back of the ICOM. The Brown NMEA IN goes to the outer core (-) of the ICOM wire.
Does this sound correct? I thought the outer core would be an earth of somekind? But the guy who adviced me said no.

[JSP]

Got this sorted through trial and error.
Icom 411's Red centre core (+) of the NMEA wire goes to the Blue NMEA wire. The outer core of the Icom's NMEA wire goes to an earth.