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Electromagnetic Log 3 (transducer and data box)


Electromagnetic Log – speed through water – with no moving parts! It will replace most conventional paddle wheels from all manufacturers!

The EML-3 electromagnetic speed log measures the boat speed through the water with no moving parts.

Robust and accurate, the sensor generates an alternating magnetic field below the boat and measures the resulting electric field produced by the boat moving through the water. This signal is converted to a pulse stream to replace any existing paddle wheel sensor.

With excellent linearity and a resolution of 0.1 Knot, over the range 0.2 to 40 Knots, the control box converts the sensor signal to a pulse output to connect to any NASA Marine paddle wheel log display (Clipper Duet, Clipper Log, Target Log, Stingray Log)

Technical Info

Pulsed output to replace exsiting paddle wheel unit

Pulses per nautical mile adjustable from 15000 to 25000 PPM

Output levels – High 5V P to P

Low 0.5V P to P

(note – the transducer is a low profile unit, the 50mm OD skin fitting included

will need to be fitted in place of your current fitting)



For a complete solution the EML-3 electromagnetic transducer and controller can be supplied together with a Clipper Duet

AIS Engine



Product video below, connected to a Clipper Duet combined Depth and Log. Shown with kind permission of one of our valued beta testers.


Speed range 0.2 – 40 Knots

Speed, trip and total logs

Pulse output to suit paddle log input


Transducer dimensions:

Hull skin fitting outer diameter = 50mm

Hull skin fitting inner diameter = 40mm

Hull skin fitting height = 70mm

Complete transducer overall height = 115mm*

*Allow 30mm minimum height clearance for cable

Cable length 5.0 metres


Box contents:

EML-3 Data box

EML Transducer with 5 metre cable

EML Skin fitting

EML Blanking plug

Fudsed power lead and Manual


Product Video

Weight 1 kg