Modern AIS receivers and transponders output high speed NMEA0183 data at 38400 baud. Therefore, it is often difficult to connect AIS data and low speed GPS or instrument data at 4800 baud to some chart plotters and/or PCs that have just one NMEA 0183 input. With the MUX100 NMEA 0183 multiplexer, all data received on the two input ports is multiplexed and transmitted on output 1 at 38400 baud. The pre-configuration means that Input 1 accepts AIS data at 38400 baud and input 2 accepts GPS/instrument data at 4800 baud.
To give position information to a DSC VHF, it often requires low speed GPS data. However, when an AIS transponder is fitted, the GPS data is often only available at 38400 baud. The VHF will ignore this. The MUX100 intelligently takes the GPS data from the AIS present on input 1 and will then re-transmit this on output 2 at 4800 baud; which you can then connect to the VHF. As a safety feature, the MUX100 will also automatically switch to the GPS data on input 2 and transmit this on output 1 and output 2. Should GPS data on input 1 be invalid or lost. To avoid duplicated data confusing other equipment, the MUX100 automatically blocks duplicated data on Port 2.
In addition, using intelligent priority switching, the NMEA multiplexer MUX100 gives priority to input 1. Input 1 will automatically switch to input 2 if GPS data is invalid or lost on input 1. When it receives valid position data again on input 1, it will automatically revert.
Two LEDs on the face of the unit indicate the data status, with a solid LED showing which port currently provides GPS position. As the MUX receives data, the other port will have a flashing light. Neither LED will be lit or flashing when NMEA data is not present.