On our boat, we have an old Seafarer D800 echo sounder. The device slowly stopped working two years ago, the depth it was able to measure went smaller and smaller, in the end it couldn’t measure at all, even if the depth was only two meters.
I’ve missed to take pictures, but the repair was very simple. There are to caps inside, at least one of them is 1uf 63v, electrolyte was leaking on one side, so I was pretty sure that it’s not good anymore. I’ve decided to replace it (only had a 1uf 50v available), and this did the trick. While I was at it, I’ve also cleaned the mode button (realized, that it was stuck), and cleaned the two pots (both are working much better now).
It is now working as it should again, I was able to measure up to 80 meters (limited by the depth, not by the sounder)!
Happy boating, the season just started here.