Airmar speed transducer
On my Swan 40 I have a Furuno FI 503 log/depth/temp combined instrument with a Airmar DST800 paddle wheel transducer. The log underreads by about 15-20% and boat speed is 15-20% too high. Comparisons are with chart plotter gps over passages of several hundred miles in a variety of conditions, in areas where tidal infuence is small (0-1 knot)
I put in a new transducer 6 months ago, same model as recommended by Furuno, but still have the same problems.
Has anyone had problems like this or ideas how to fix ?
Thanks
Richard Forrest