3 wind transducer, 4 compass transducer, 5 gps receiver – Nexus 21 NX2 User Manual
Page 17: Wind transducer, Compass transducer, Gps receiver, Server

SERVER
2.9.3 Wind
transducer
All our wind transducers can be used.
2.9.4 Compass
transducer
Only the Nexus version can be used.
Compass transducer for S-5000, D50, S-520/S-525 and POWER
can be upgraded to Nexus standard. Contact your local Nexus
dealer for a quote.
2.9.5 GPS
receiver
The NX2 GPS antenna (and other NMEA antennas) is connected
to the Servers NMEA input marked NMEA GPS.
16