Topic: I eliminated Minnkota trolling motor interference

[jimham82]

My boat has a Minnkota Fortrex 101 trolling motor and a 1197C SI unit at the bow with a SI transducer mounted on the trolling motor.   When I stepped on the power for the trolling motor, the interference was pretty bad.

My Minnkota has the universal transducer built in, which was not being used.  I ran a 18 guage ground from the negative of the crank battery up to the front and wrapped it around the metal end of the universal transducer.   This effectively eliminated the interference.

A few other things I did previously that helped, but didn't eliminate very much interference:

I ran a 18 guage ground from the negative from the trolling motor battery to the negative on the crank battery providing an earth ground.   Be sure to put a 2 amp fuse on this one.

I went to Radioshack and bought some RF chokes and installed two on the power connectors to the front 1197 SI.   

[sonar2000]

Good job.

Most boats do not have a grounding connection thruout the boat because of the material used in construction.

Isolation grounds  can serve as antennas from every thing RF thru electrical motors. And even gas motors because of their electronics..

Great that you took the time to do all that you did and you are the better sonar user for your time..

Thanks for sharing..

Chuck

[Gattlin]

 This Sounds like something good to know can you snap a picture by any chance? I rig my own so it would be good to see:)

[jaygreen]

I just installed a new Minnkota Fortrex 101 and mounted the transducer for my 788CI HD DI unit on it.   Finally got the boat on the water to try all this out this afternoon
and things work great, except for the interference when I engage the trolling motor.  I have the US2 transducer too and it is not in use either.   In the original post, you stated "I ran a
18 guage ground from the negative of the crank battery up to the front and wrapped it around the metal end of the universal transducer."  Can you elaborate on what wrapping
it around the metal end of the universal transducer means?  Are you referring to the metal connector on the trolling motor transducer cable that I just hid unused behind my front gauges?

Jay

[ZX225SK]

how did you attach the wire around the universal transducer could you post a picture

[Humminbird_Greg]

I just installed a new Minnkota Fortrex 101 and mounted the transducer for my 788CI HD DI unit on it.   Finally got the boat on the water to try all this out this afternoon
and things work great, except for the interference when I engage the trolling motor.  I have the US2 transducer too and it is not in use either.   In the original post, you stated "I ran a
18 guage ground from the negative of the crank battery up to the front and wrapped it around the metal end of the universal transducer."  Can you elaborate on what wrapping
it around the metal end of the universal transducer means?  Are you referring to the metal connector on the trolling motor transducer cable that I just hid unused behind my front gauges?

Jay

Jay, you need to make sure that the internal connector for the US2 cable is tight – even if you are not using it.  Be sure and check the internal fuse with a meter while you are in there as well.

[jimham82]

Two things.  First check to make sure the fuse in your Fortrex head is not blown.  If it is working the light will work on your direction indicator when you step on the power button. Second, I just wraps the ground around the metal connector of the universal transducer.