The 1NMEA to4 is designated for the distribution from one serial data source (NMEA or RS 232) to max. four receivers (RS 422 or NMEA). In case of usage of NMEA source the RS 232 port can be use for a monitoring of a data string. The four outputs of the module are selectable with the help of switches to RS 422 or NMEA. The NMEA input channel is galvanically isolated from the system and the power supply.