NMEA
Pronounced “knee-ma,” this is the National Marine Electronics Association. Products meeting NMEA standards are clearly indicated, like the Good Housekeeping Seal on your fancy French mandoline.
NMEA 2000
This is the latest standard for serial-data networking established by NMEA, operating 50 times faster than NMEA 0183. Warning: 0183 instruments may not be compatible with newer NMEA 2000 units. Ask the merchant or manufacturer to determine information-sharing possibilities.
IPX6 and IPX7
These are among standards of waterproofing established by the International Electrotechnical Commission (IEC). An IPX6-rated device takes spray, driving rain and breaking seas. An IPX7 device is submersible to 3¼ feet (1 meter) for 30 minutes.
DSC
This stands for digital selective calling on VHF radios. Press DSC and a distress call goes out on Channel 70 with your preregistered ID, and exact position if connected to a GPS.
NIT
This measurement of light in candelas per square meter (from Latin nitor meaning brightness) is used to compare panel displays. A true sunlight-readable display has 1,000 nits of screen brightness and a contrast ratio greater than 5 to 1.
AIS
This is the Automatic Identification System that can be a standalone receiver or a feature of newer VHF units. When connected to a GPS or radar, it will show you the location and identity of other AIS-equipped boats, aiding in collision avoidance.
WAAS
What is WAAS? Wide Area Augmentation System: It collects and refines satellite information to bring GPS accuracy to within an incredible 10 feet.
