I currently installed a new Elite 7 HDI and a MinnKota powerdrive 24 Volt (does not have universal sonar) on my boat. Everything works properly when the TM is not going. As soon as I hit the go button on the foot pedal I have bad interferance. It distorts the picture best described as it looks like turbulance in the water. I heard putting a ground from TM batteries to cranking batteries but my TM batteries are in front of my boat. Ive also heard of an RF choke. Or ive also thought about putting a piece of rubber between by cable clamp for transducer and motor. Any thoughts?