If you mount the transducer that comes with the Humminbird SI unit's in the right spot on your boat it will work at higher speeds for regular 2d depth readings and at low speeds for SI readings.
I can get depth readings at my boat's max speed and also get the SI to work at 4 mph and slower.
It all depends on your boat and where you mount the transducer.
I mounted my transducer on the back of my boat and about 16" away from the center line of my boat where the prop is located. Also you should look at the prop and determine if it turns clockwise or counterclockwise and mount the transducer on the side of least turbulence.
Air bubbles will stop the sound waves from going though at the same speed as they would in just water. So you must avoid air bubbles and turbulence around the transducer location.
Note: My boat's top speed is only 20 mph and the bottom of my boat is flat with rivets along the bottom.
I'd check other web sites and try to find some one else with a boat like mine if I wanted to know where to located the transducer to make it work at high speed and low speeds.
There are other web sites where people have posted pictures of how they mounted their transducers on many different types of boats.
Not everyone has chosen to use two separate transducers. Again it may depend on the shape of your boat's hull and transom.
Originally Posted by slimshad09
Reply With Quote