Eagle FishElite 640c Installation And Operation Instructions Manual page 33

Transducer location Transducer location
(high speed) (trolling speed)
Shoot-thru-hull transducer locations for
high speed or trolling speed operation.
To choose the proper location for shoot-thru-hull mounting, follow these
testing procedures: (You may need a helper to complete these steps.)
1. Anchor the boat in about 30 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 in the water. Adjust the sen-
sitivity and range controls until a second bottom echo is seen on the dis-
play. (You'll need to turn off Auto Sensitivity, Auto Depth Range and
ASP. Try a range setting that is two to three times the water depth. The
harder (more rocky) the bottom, the easier it will be to get a second bot-
tom signal.) Don't touch the controls once they've been set.
True bottom
Second bottom
Manual range setting
Example of a second bottom signal. Unit is in 30 feet of water with
range set at 80 feet and sensitivity set at 87 percent.
2. Next, take the transducer out of the water and place it in the water
in the sump of the boat, face down. Notice how the signal strength de-
creases. The second bottom signal will probably disappear and the bot-
tom signal intensity will likely decrease.
3. Now move the transducer around to find the best location with the
strongest possible bottom signal. If you find a spot with an acceptable
bottom signal, mark the location and move on to step 4.
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