To choose the proper location for
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 sensitivity and range controls until a second bottom echo is seen on the display.
You will 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 bottom signal. Do not touch the controls once they have 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 to 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.
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