[TG] Rv100 shows deep depth falsely

[Quinn h pearson]

Got a pair of axiom 9’s with an rv100 transducer and a b60 connected via the Y cable.

When I leave the dock at 3 knots, the sounder will show 899 plus feet of water in only 25 feet until I get up to 15 knots or better and then it’s fine for the day.

The transducer is clean, just a bit of growth on the sides but none on bottom, and if I go out on the water tomorrow , the same thing will happen so there’s no way I’m growing enough slime in one day to do this.

The b60 is in the hull at mid ships and always performed fine when it was connected to my old c120

All equipment is software updated as of July 2018

Why the deep reading when I first leave?