Cm599LH picture problems

[JasonM]

What would be causing this on my low frequency?
It seems like the transducer is skipping on and off cause there will be blank spaces and all of a sudden a lot of noise when the high frequency does not show the same picture.

 

[Magnetron]

It looks less like noise and more like cavitation IMHO.

- Maggy

 

[Deep Blue]

JasonM,

What you are seeing is a classic case of turbulence that is happening to the fishfinder's transducer. When it comes to turbulence, it will affect the Low Frequency side before affecting the High Frequency side.

How is the transducer mounted on your vessel and what is the vessel's speed when this begins to happen..?

- Deep Blue

 

[JasonM]

JasonM,

What you are seeing is a classic case of turbulence that is happening to the fishfinder's transducer. When it comes to turbulence, it will affect the Low Frequency side before affecting the High Frequency side.

How is the transducer mounted on your vessel and what is the vessel's speed when this begins to happen..?

- Deep Blue

Hi Deep Blue,

The transducer is pocket mounted at the keel of the boat. That was the boat just sitting still under no power and drifting. We drop 5lb leads here with chum below the boat 50-100 fathoms deep and sometimes we won’t see them on our finder. I had a 1kw transducer before that was able to pick them up but this 3kw is not as consistent and not able to mark fish clearly.

 

[Deep Blue]

JasonM,

That picture on Low Frequency is simply horrible. So I'd go back and do a factory default on sounder settings and see if that changes anything.

Also you might want to power off all the electronics on the vessel (except for the sounder), and see what happens. You are clearly getting some type of interference from something, either its electrical or acoustic or both.

Its there an Earth Ground that is attached to the MFD..?

- Deep Blue

 

[JasonM]

JasonM,

That picture on Low Frequency is simply horrible. So I'd go back and do a factory default on sounder settings and see if that changes anything.

Also you might want to power off all the electronics on the vessel (except for the sounder), and see what happens. You are clearly getting some type of interference from something, either its electrical or acoustic or both.

Its there an Earth Ground that is attached to the MFD..?

- Deep Blue

Hi Deep Blue, thank you for the fast response. I’m assuming there is an earth ground attached to the MFD done by the boat builder. I’ll open up the console and check. I thought it could be interference as I also have a multi beam sonar but when I had those issues I turned it off and the problem persisted. The pictures you see are with only the cm599 transducer on. Everything else is turned off. I’ll try a factory reset the next time I have it submerged and see if that fixes the issues but I believe I did it before.

 

[JasonM]

JasonM,

That picture on Low Frequency is simply horrible. So I'd go back and do a factory default on sounder settings and see if that changes anything.

Also you might want to power off all the electronics on the vessel (except for the sounder), and see what happens. You are clearly getting some type of interference from something, either its electrical or acoustic or both.

Its there an Earth Ground that is attached to the MFD..?

- Deep Blue

Aloha deep blue, my boat builder was asking where do they recommend the earth ground be attached to? He said he don’t remember having an earth ground. Where would I need to run the grounding wire? Could I just run it to the negative bus bar? This is the response of my boat builder “You should clarify with them. Usually I attach it to the bonding system, but you don’t have one.”

 

[Deep Blue]

JasonM,

Boat bonding systems are a network of electrically connected metallic parts and components. They provide a path for ground-fault currents, prevent touch-voltages on metal surfaces and provide a path for stray currents.

Usually you would connect the MFD's Earth Ground to the vessel's bonding system. Since you don't have that as an option, you'll have to find the next best thing like connecting the earth ground to something like an engine block, or rudder posts.

Do not connect the MFD's Earth Ground the the vessel's electrical system Negative Bus Bar. This has the potential to cause a "ground loop" and will make the interference worse.

- Deep Blue.

 

[JasonM]

Deep blue, is there any specific frequency for the bonding system?

 

[JasonM]

Would I be able to hook it up to a thru hull fitting or that wouldn’t count as ground?

 

[Deep Blue]

JasonM,

Sure. You can give it a try and see if that improves the noise issues.

 

[lukahill]

Hi JasonM,

How did you go with the grounding?

Did it resolve your issues?

Thanks