Humminbird 1158c Combo Installation And Operation Manual page 53

1. Locating the Transducer Mounting Location
Decide where to install the transducer on the inside of the hull. Consider the following to find
the best location:
• Observe the outside of the boat hull to find the areas that are mostly free from turbulent
water. Avoid ribs, strakes and other protrusions, as these create turbulence.
Areas of Possible Turbulence
Rivets
Transom
• As a general rule, the faster the boat can travel, the further aft and closer to the
centerline of the hull the transducer has to be located in order to remain in contact with
the water at high speeds.
2. Trial Installation
You will not be able to adjust the mounting after an inside the hull transducer is installed. It is
best, therefore, to perform a trial installation first that includes running the boat at various
speeds, in order to determine the best mounting area before permanently mounting the
transducer.
1. Plug the transducer into the control head, then power up the control head. When the
control head detects a functioning transducer, it will automatically enter Normal
operating mode.
2. View the sonar signal at its best by holding the transducer over the side, immersed in
the water, so that it is pointing straight down over a known flat bottom. Use the display
to benchmark against the sonar signal that will be detected once the transducer is
placed in the hull.
3. Place the transducer body face down at the identified mounting location inside the hull,
with the end that has the mounting knuckle pointed towards the bow of the boat.
Strakes
Hull
41
Stepped Hull
Step
Inside the Hull Mount - DualBeam™ PLUS
Rib