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How Many NMEA Devices can I Connect to my Garmin Aviation Device?
The larger Garmin aviation portable systems such as the GPSMAP® 196, GPSMAP® 296, GPSMAP® 396, GPSMAP® 495, GPSMAP® 496, and GPSMAP® 696 can normally be connected (in parallel) to three NMEA devices.
The GPSMAP® 96, and GPSMAP® 96C can only be connected to one NMEA device.
The aera® 660 and aera® 760 devices can be connected to two NMEA devices.