Lowrance M56 S/Map Installation And Operation Instructions Manual page 36

Portable transducer installed on boat transom.
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.
NOTE:
When you first turn the unit on, the Map Page appears. If you'd
rather start learning about GPS operation first, turn over to Sec. 6,
Basic GPS Operations. (Remember, you don't need to read this
manual from cover-to-cover to get going. We designed it so you can
skip around to the section you want to read.)
Suction
cup
Hull
30
Bracket
Transducer