[DG] [DG11] A70D losing bottom

[Windy619]

I have recentlyacquired a boat with an A70D installed which will only show a depth and bottom display above approx 5 metres. I have discovered that the transponder is a transom model but has been moved to within the vessel and 'stuck' to the inside of the hull with what appears to be mastic of some variety. Could this be causing my problems?

[Derek - Raymarine - Moderator]

HI Windy619

Thank you for your enquiry.

I am afraid this installation is the most likely cause of the issue. There are very specific transducers for mounting inside the hull of a boat, and mastic is also not a recommended method for securing them.

There is a lot of information described here as well as on the Raymarine website click here

The problem with the mastic could be that it is absorbing some of the signal from the transducer and possibly the Mastic may have some air bubbles in it as well and this will also inhibit operation.

If possible we suggest reverting to a transom mount transducer, since this will improve performance.
thanks
Derek