[TG] [TG11] Axiom sounder image clutter with RV transducers

[Strbass28]

Hello Raymarine Suport,

I have upgraded my Raymarine unit to from the A series with a CPT transducer to Axiom with rv212 bronze transducers and I'm not happy. I'm thinking it's a problem with the installation. Great care was made for transducer placement and it's a spot that has worked very well for previous installations.

Since upgrading I have noticed a lot more clutter in the sonar picture and i'm trying to figure out why. The basic chirp sonar shows a lot more stuff in the water column and it's definitely not fish. This is especially true for the top of the water column, like first 30 feet. This was not happening with my A series unit and CPT 110 transducer. So basically I found the A unit and CPT 110 transducer was a lot more effective at spotting fish and easier to look at. The real vision on the axiom is totally useless because it picks up too much interference. The crazy making is the returns look a lot like legit fish returns, but they're not. The returns are blob like markings, not a fuzz

#0 tested with November 2019 axiom software release.
#1 With Axiom I get a good bottom picture at 30knts in calm seas. 25knts in chop.
#2 Bottom looks pretty good at 500' depths. After that I begin to lose bottom. It's the in-between that has a lot of clutter. Particularly the first 20'-40'.
#3 At 40 foot depths there is significant clutter that looks like fish blobs.
#4 interference happens even when boat is drifting with no motion or rocking.
#5 It does mark fish, but it's always marking something so it's annoying to read.
#6 observations are made primarily with auto adjustment settings. I have played around a lot with the settings and nothing helps. I have reset to factory defaults. In order to get the interference away I have to adjust the filters so low that it doesn't mark fish and bottom returns are weak.
#7 starboard Transducer is placed in the same place where the CPT110 worked incredibly well. port transducer is in a symmetrical place.
#8 I run the transducer cable along with the +12V to the helm. Same that I did with the CPT110 cable. It's possible that this is causing interference but I doubt it. I did some minor experiments and did not see a difference but I could do some more if you really think that being within a couple inches of a 4awg +12v wire could make a difference. Skeptical on this.
#9 I have tried connecting the transducer to my axiom 12 and 9 inch units and have the same results.
#10 I'm happy to provide images. I'll get to work on that this weekend.

Any suggestions? It does not look like this is a common problem. I updated my units for real vision and that does not appear to be useful at all with how it's working so i'm very disappointed. Please help.
Thanks,
strbass28

[Tom - Raymarine - Moderator]

Hello Strbass28,

Yes, please do send us images, I'll be able to give you more concrete information once I can see what you're seeing. A couple of comments in the meantime though:

• If you haven't done so already, I'd suggest having a read through this FAQ on sounder performance troubleshooting. I wrote that some time ago to help answer this sort of question.
• If you have lots of near-surface clutter then you can reduce that with the Surface Filter control in Menu > Adjust Sensitivity. Surface Filter is effectively the old TVG which is used to selectively suppress near-surface clutter. You should use the lowest level of SF that you can - too high and you can suppress wanted returns - but it will help clean up the top part of the water column if you have a lot of clutter from particles in the water, wave action etc.
  

Once you can post some clear images back - both as you normally use the sounder and also ideally in the diagnostic gain setup described in the FAQ - then I can go further.

Regards,
Tom