[michael in parker]

I have a bought Eagle Cuda 168 fish finder as a beginner fish finder and I am having difficutly adjusting the fish finder to get accurate readings. The transducer is mounted to my trolling motor (There are not to many options on my inflatable pontoon boat) and I get a lot of interference. When I put my hand on the motor while turned on, I feel a lot of vibration. Is this affecting the transducer? If I don't turn the sentitivity to 50% and turn on the noise reducer on high, then my screen goes crazy and shows ton's of fish. Lately, if I see a fish or a school of fish on my sonar I am not sure if it is my fish finder or if I am really seeing fish. Even when I turn the motor off, I get a bunch of junk on my screen.

Do any you have suggestions on how I can get a more accurate reading. How do I know my sonar is not broken. Thanks for your help.

 

[farmer ted]

I'm no expert but it could be either vibration from the motor as you suggested or possibly electrical interference from the motor itself. One way to test this theory would be to temporarily put the transducer somewhere away from the motor...even just holding it in your hand for a minute to see if the unit acts normally.

 

[kirbydog]

Do you have the fishfinder going to the trolling battery or do you have a starting battery. If you do, it should always be wired to the starting battery. Another thing you could do-they sell those little batteries (Sportmans has them) and you could have a seperate battery just for the fishfinder. Also, make sure the transducer is not real close to the turbelence created by the tolling motor blades-move it forward if it is-an inch can make a difference.

 

[laker taker]

If I don't turn the sentitivity to 50% and turn on the noise reducer on high, then my screen goes crazy and shows ton's of fish.

Something is wrong. If your running the filter on high settings, your filtering out detail you'll want to see. I agree with Kirbydog's post and Farmer Ted. I've never had motor interference or vibration causing feedback on my transducer. I have a six beam unit on my bowmount and no problems. I have had bad transducers before, try the other suggestions then start questioning your unit.

 

[GMCO45]

Probably no starting battery on an inflatable pontoon.  If it is interferrance from the
trolling motor, the suggestion of a small 12V battery dedicated to the fish finder should solve that.
Have seen them at Gander Mtn. for $19.99 with a charger and $14.99 without the charger.

 

[tuppergun]

Also be sure the extra wire to the transducer is coiled in a fig. 8 and not in a circle or a ball and just stuffed away. I learned that the hard way

 

[kirbydog]

Snag-Curious about why it should be in a figure 8? Mine is just looped in a ball with some electrical tape.

 

[work2fish]

I agree with everyone else on the need to do more tests. Here is what I would suggest:

1) Find a spot in which you are pretty sure there is nothing below you.

2) Turn of the automatic fish ID and look at the actual returns. I've found that the automatic fish ID will often show more than is really there unless other settings are adjusted perfectly. It is a good idea for you to learn to interpret the actual sonar signals anyway.

3) Temporarily mount the transducer on something all by itself -- I am thinking of something like a piece of wood with a mounting brace on it.

4) Compare your results with the trolling motor off and on to look for intereference.

5) Once you are sure the trolling motor is not causing interference, adjust the sensitivity settings until the noise just disappears. Move around the lake and look at the returns to see if they are what you might expect.

6) Mount the unit back onto the trolling motor and watch to see if vibration is causing the bad stuff to show up.

This way you can hopefully determine if the problems are due to 1) vibration from the trolling motor, 2) interference with the trolling motor's wiring, 3) the settings on the finder or 4) a faulty unit.

Lowrance's fishfinder tutorial can be helpful in using the settings and interpreting the readings you are getting back to know if they are realistic:

http://www.lowrance.com/Tutorials/Sonar/sonar_tutorial_01.asp

Hope this helps.

 

[tuppergun]

Kirbydog, I run a Eagle 480 and had trouble when I first put it in my alum. boat. I called Eagle and they said to try that first, I did and all the problems went away! Don't really know why ,but it worked.

 

[bobber]

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