Eagle CUDA 250 S/Map Installation And Operation Instructions Manual page 50

NOTE:
For optimum operation, the portable transducer should be adjusted
so that it is parallel to the ground. For more information on this,
see the earlier segment on Transducer Orientation and Fish
Arches.
Now that you have your unit installed, move on to Sec. 3, Basic Sonar
Operations. There, we'll present a series of step-by-step tutorials to
teach you the basics of your sonar operation.
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