Humminbird 1158c Combo Installation And Operation Manual page 54

4. Fill the hull with enough water to submerge the transducer body. Use a sand-filled bag
or other heavy object to hold the transducer in position. The transducer cannot transmit
through air, and the water purges any air from between the transducer and the hull,
and fills any voids in the coarse fiberglass surface.
5. View the sonar signal on the display and compare against what you observed in Step
2, making sure that the boat is in the same location as it was during your observations
in Step 2. If the results are comparable, move on to Step 6. Otherwise, locate a new
position in the hull and repeat Steps 3 through 5.
6. Run the boat at various speeds and water depths while observing the screen on the
control head. If depth performance is required, test the transducer in water at the
desired depth. If the performance is acceptable, move on to Step 7. If the performance
is not acceptable, repeat Steps 3 through 6.
7. Once you have determined the best mounting location using the above steps, mark the
position of the transducer.
3. Routing the Cable
1. Once the mounting location is determined and you have marked the position of the
transducer, route the cable from the transducer to the control head.
Inside the Hull Mount - DualBeam™ PLUS
Preferred Mounting Area
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