Re: GPS/VHF DSC wiring?
The Garmin NMEA output and baud rate will have to be enabled/configured in one of the setup menus. The DSC radio's "NMEA input -" will connect to the Garmin's small black wire, pin 2 "ground power & data". The radio's "NMEA input +" wire will connect to the Garmin blue wire, pin 3, marked as "NMEA out" (com 1 TX).