Will the NGX-1 transmit data on its NMEA 0183 output that is received on the NMEA 0183 input?

This is unfortunately not possible.  Doing so would create a data loop which will quickly use up the narrow bandwidth available to NMEA 0183 devices and prevent vital data from being transmitted.

For more information on NMEA 0183/NMEA 2000 and how it works, please download our free guides here: https://actisense.com/actisense-hub