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I have a 34' Beneteau sailboat. I am trying to add a E120 Clasis MFD and a new wind instrument to my existing system Seatalk system. The existing system includes a RC 320 Chart Plotter (Not needed except it feeds the antena to the system) a Tridata and a Auto Pilot. What is the correct method. VHF is also tied in.
From what you describe I believe the most efficient means of connecting will be using Seatalk. If you introduce newer equipment that utilizes NMEA-2000 or SeatalkNG (Raymarine's implementation of NMEA-2000 with proprietary connectors) you will be able to utilize Raymarine's Seatalk to SeatalkNG converter (Raymarine P/N R52131).
The E-120 is itself an effective NMEA-2000 to seatalk converter.