NASA Electromagnetic log + Data box + Clipper EM log display

The rugged and accurate NASA electromagnetic Log and Velocity data box EML-2 measures boat speed through water with no moving parts. The sensor generates an alternating magnetic field under the boat and measures the resulting electric field produced by the boat moving through the water. The EML-2 data box calculates with excellent constancy; boat speed, trip and total distance with a resolution of 0.1 knots over the range of 0.2 to 40 knots. The NMEA0183 VLW + VHW output can be connected to the NMEA0183 input of an instrument or computer. 

EML-2 data box + sensor: Skin penetration: 50 mm. 

Available as data box with sensor or as complete Clipper system.