Seatalkng/NMEA2000 Power

[Chuck - Raymarine - Moderator]

ledouxjj.

The earliest generation of DSC VHF radios supported one way NMEA 0183 communications to support receiving GPS data from the marine electronics system. This GPS data would be used by the VHF radio in it RF transmissions to permit receiving DSC VHF radios to receive your vessel's coordinates. Currently manufactured DSC VHF radios support not only this capability, but also support transmission of DSC report data (type of message, coordinates, etc.) received from another vessel to the vessel's chartplotting system. Bidirectional NMEA 0183 communications between two devices requires four leads. Should only two of the VHF radio's NMEA 0183 leads be interfaced to the navigation system and should the VHF radio be reporting that it is getting a GPS position FIX, then the VHF radio would be deemed to be interfaced via one-way (marine electronics -> VHF radio) communications, and the marine electronics would then correspondingly not be receiving the DSC data required to automatically plot DSC messages received by the VHF radio.