I own an older model Catalina 320 that came equipped with an Autohelm system. Since Autohelm is now defunct, I am having a problem replacing the four-blade, high speed paddlewheel speed sensor (transducer) part # 610-0A-129. Thanks, Dave David Yaman Realty Services 839 NYS Route 13 Cortland, NY 13045 (Phone) 607-756-5872 (Fax) 607-758-3776