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transducer installation can be made on hulls with flotation materials
(such as plywood, balsa wood or foam) between layers of fiberglass if
the material is removed from the chosen area.
Epoxy the transducer to a solid portion of the hull.
For example, some (but not all) manufacturers use a layer of fiberglass,
then a core of balsa wood, finishing with an outer layer of fiberglass.
Removing the inner layer of fiberglass and the balsa wood core exposes
the outer layer of fiberglass. The transducer can then be epoxied di-
rectly to the outer layer of fiberglass. After the epoxy cures, the hull is
watertight and structurally sound. Remember, the sonar signal must
pass through solid fiberglass. Any air bubbles in the fiberglass or the
epoxy will reduce or eliminate the sonar signals.
WARNING:
Do not remove any material from your inner hull unless
you know the hull's composition. Careless grinding or
cutting on your hull can result in damage that could sink
your boat. Contact your boat dealer or manufacturer to
confirm your hull specifications.
To choose the proper location for thru-hull mounting, anchor the boat in
60 feet of water. Add a little water to the sump of the boat. Plug the
transducer into the sonar unit, turn it on, then hold the transducer over
the side of the boat. Adjust the sensitivity and range controls until a sec-
ond bottom echo is seen on the display. (You will need to turn off both
automatic and ASP
.) Don't touch the controls once they've been set.
Next, take the transducer out of the water and place it in the water in
the sump of the boat. Observe the sonar signal to see if there is a no-
ticeable decrease in sensitivity. The second bottom signal may disap-
pear and the bottom signal may decrease in intensity.
Move the transducer around to find the best location. If the sensitivity
control must be increased greatly to compensate, then the transducer
should be mounted on the outside of the hull. If not, then mark the lo-
Fill with epoxy
Inner hull
Epoxy to hull first
Outer hull
Flotation material
