Raymarine forum

Hi All,

Im really keen to get some feedback on issues with depth on a new Raymarine setup. I took delivery of a new dealer configured 6.2m aluminium fishing boat with a pair of flush mount Axiom 9’s, NEMA GPS module and an RV-100 transducer installed.

- Both Axioms are running the latest updates and I sync via Navionics on iOS.
- I’ve made a few dashboard cards for chart/sounder but all sounder settings have been left totally default.
- I’ve made a few minor chart customisation to show live sonar data etc.
- I’ve performed a “sounder reset” at some point but the issues persist.
- I regularly lose the bottom with sonar and downvision (see videos) and there is no reliable way to get it back.
- Realvision 3d is unreliable and sometimes produces intermittent mapping (see videos)
- I’ve had 13 hours on the water, in water ~25meters to ~1.5meters and the issues are consistent.
- Perhaps, maybe coming to a dead stop has returned the depth, but it is so intermittent it is hard to be sure.

The videos show the issues really clearly, I also have a picture of transducer install attached too.

Hello racerx,

Sorry for the delay replying.

Thanks for the videos, that's really helpful. What you're seeing in the Sonar channel and at the start of the video in DownVision is what we call 'Bottom Search' mode, when the sounder's cycling through different ranges and pulse-lengths in order to try to acquire bottom lock. Once the system does get a lock in the DV video, the bottom signal looks very weak, which explains why it took the time.

When you have a weak-looking signal, the problem is either that the bottom echo really is weak or that there's a high background noise that's causing the system to have to drop the gain - in order to try to keep the noise clutter off the screen - and is also ending up tuning out most of the bottom echo as well. In order to tell what's happening we need to run some tests in all Manual gain setup, as described in this FAQ.

Has the system always done this?

If you can have a look at that FAQ and then send us some images in the all-manual setup it describes, we'll be able to tell you more about what's going on.

Thanks,
Tom