posted 06-12-2008 08:23 PM ET (US)        

But: the depth that registers digitally on the upper left blinks rather erratically and randomly, and the screen display doesn't register depths or bottom contour/structure at all.

When I feel the transducer the 'thumping' is also rather erratic, a period of say a thump per second, then a staccato thumping for a period, like a machine gun, then a kind of calypso beat for a while.

What's wrong with my unit? It's worked flawlessly for the past 3 years, including the past April week in Hattaras, NC.