Hi I am hoping someone can advise.
I have a new to me Raymarine ST60 Tridata and the displayed speed is approximately half of the GPS speed despite a spotless clean Transducer.
The Depth and Sea Temperature all looks o/k.
Transducer you say and I would tend to agree but I have mixed test results which is confusing.
I am assuming the Transducer is an M78712 although I cannot confirm this, all the connections look o/k! Spinning the paddlewheel by hand and I get a reading on the display – however the Raymarine test instructs you to connect a multimeter between the removed green and shield connectors and slowly rotate the paddle wheel. You should get an open and closed circuit for each quarter turn – I get nothing!!
I can get a replacement Transducer which is the E26031 I believe, but just wondered if it was a waste of time giving the test results?
Has anybody had similar problems or should I upgrade the whole unit?