[TG] [TG11] Axiom 9RV 3D Depth

[Tom - Raymarine - Moderator]

Hello donaldreeder,

Quote:The realvision 3D depth has a problem finding the bottom when the depth is greater than about 650'. I have a pair of RV-320 20 degree transducers. I was expecting to be able to read to about 1000'.

Depending on which channel you're using (3D, SideVision, DownVision or Chirp Sonar) you'll get different deep-water results but 650' is pretty reasonable for that transducer type. 900' is the absolute perfect-conditions maximum for the Chirp Sonar channel which gives the best depth performance.

Quote:Is there a way to be able to read the top 300' or so regardless of the actual depth even though the instrument can't find the actual bottom? I would like to be able to find fish in this upper region.

Yes, just go to manual Range (in the menu on the fishfinder page) and range to 300'. You may get an incorrect depth reading if there's something within that range to get a strong echo off - bait, thermocline - but otherwise should work fine.

Quote:how would I add a CP370 with a 1KW transducer to be able to read to 500'?

You can attach any current sounder module, including CP370, to the Axiom's Raynet network port. You shouldn't need 1kw to reach 500' though - a 600W transducer should do that with no problems. A CP370/1kW will give the following advantages:
- better sharpness and clarity through the higher-quality transducer
- better sensitivity to smaller/weaker targets in deep water
- retaining the use of the current Chirp Sonar channel (if you were to use a 600W transducer, e.g. P66, connected to the Axiom via a Y-cable then that would repurpose and take over the current Chirp Sonar channel and divert it to the 600W, 50/200kHz transducer.)

I hope this makes sense,
Tom