Engine / electronics noise affecting fishfinder performance?
While most bottom loss and noisy plot fishfinder performance issues are associated with aeration of the fishfinder transducer, these performance issues may also be caused by electrical interference. Should the problem manifest itself while the vessel is not being propelled by power or sail, then it would be recommended that all electronics except for the fishfinding electronics, electrical circuits, generators, shore power, and engines be switched OFF. Should the problem persist, then it would be recommended that the fishfinding product be sent to Raymarine’s Product Repair Center to be bench checked / serviced. However, should the problem abate when operating under this quiet ship mode of operation, then it would appear the performances issues are indeed being caused by electrical interference. Electrical interference from engine systems is easily tested by bringing the boat up to the speed that the bottom contact begins to be lost or noise within the plots is observed, and then noting the engine(s) RPMs. The boat would then be stopped, the engine(s) shifted into neutral, and the engine(s) RPMs then increased to the previously noted RPMs. Should the fishfinder maintain bottom contact and no noise be observed within the fishfinder plot, then the fishfinder performance issue would be deemed to not be caused by electrical noise from the engine(s).
The most common cause of such interference is bundling of the transducer cable with engine cables, power cables, and the cables from other electrical devices.
RAYFAQ#
While most bottom loss and noisy plot fishfinder performance issues are associated with aeration of the fishfinder transducer, these performance issues may also be caused by electrical interference. Should the problem manifest itself while the vessel is not being propelled by power or sail, then it would be recommended that all electronics except for the fishfinding electronics, electrical circuits, generators, shore power, and engines be switched OFF. Should the problem persist, then it would be recommended that the fishfinding product be sent to Raymarine’s Product Repair Center to be bench checked / serviced. However, should the problem abate when operating under this quiet ship mode of operation, then it would appear the performances issues are indeed being caused by electrical interference. Electrical interference from engine systems is easily tested by bringing the boat up to the speed that the bottom contact begins to be lost or noise within the plots is observed, and then noting the engine(s) RPMs. The boat would then be stopped, the engine(s) shifted into neutral, and the engine(s) RPMs then increased to the previously noted RPMs. Should the fishfinder maintain bottom contact and no noise be observed within the fishfinder plot, then the fishfinder performance issue would be deemed to not be caused by electrical noise from the engine(s).
The most common cause of such interference is bundling of the transducer cable with engine cables, power cables, and the cables from other electrical devices.
RAYFAQ#