I have an Eagle Fishmark and had an extra transducer sitting around. Last year I decided to mount it on the transom and compare the signal to the one in the hull. It worked fine until this year when the signal got weak. I can feel and hear it ticking but it does not pick up fish well and even the bottom signal is weak. Nothing has changed on the mount. I thought maybe it had moved and was not pointed straight down. I have had transducers go out but I believe this is the first one that just got weak. I thought maybe it was the power because it is one plug but voltage is same as the in hull. Anyone seen this? I am about to join the 21st century and buy a new unit but curious about this.