The reason I ask is that the transducer on my downrigger is dead and I called the company and they said "You should only expect about 3 years out of a transducer as the this the life expectancy"
Really, I said? I thought they last forever unless damaged.
So I replaced it with a new one and the other day I had some problem with the transducer on my main unit which is about the same age. This is an airmar tri-ducer depth, speed and temp, the speed and temp work but the depth was flaky. I scrubbed it off checked all the connections and it didn't do much. Came home, ordered a new one. This AM it worked great, didn't miss a beat even at 30 knots
I will be going out again later this afternoon and will check it out in some deep water. Maybe it was just a hickup in some software. First time I ever saw a problem with that though.
In a week I will probably be the proud owner of a spare transducer.