Lots of Noise

[banksdd]

hi, I have a cpt-120 connected to an A98. When i am fishing in shallow water where the cpt-120 can see the bottom the reading seems to be ok. I see the bottom and fish, ext. When i am fishing blue water, i.e depth of 3000 plus feet the screen has a lot of noise on it that looks like small dots everywhere. i am not interested in seeing the bottom but just the first 200 feet of the water column. I have attempted to use the noise and gain filters without any success. Is there something i need to be doing when i am fishing in deep water?

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Dan,

When fishing in water depths greater than 600' and/or the sounder is unable to acquire bottom, then the sounders filters will be adjusted to their greatest level of sensitivity to better improve the chance of getting a bottom return. When using the product under such conditions, it is recommended that
- the depth range be manually configured to the desired depth range within the first 600' of the water column
- the Noise Filter setting be switched from Auto to Manual and that the sensitivity be reduced to decrease the noise to an acceptable level
- the Gain and Color Gain settings be switched from Auto to Manual and that they be reduced to decrease the noise to an acceptable level