In Hull Transducer

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Steve,

I have a concern about your comment regarding performance at any speed, as it may indicate a problem within the MFD's fishfinder circuitry. Please click here to view a FAQ addressing this subject. At trolling speed (i.e. speeds up to approximately 8 mph, is the fishfinder tracking the bottom and marking fish? If not, then it is recommended that the MFD be sent to Raymarine’s Product Repair Center to be bench checked / serviced. However, should the the fishfinder track bottom and mark fish under these conditions, then an aerated flow of water may be preventing the system from tracking bottom at higher speeds. If so and as you have suggested, the P319 would typically be recommended for those seeking a thru-hull transducer for a planing hull. However, should a thru-hull not be desired and a transom mounted transducer not be suitable for the hull, then it would be recommended that the A80170 P79 transducer would typically be recommended.