How to Use a 797 SI Humminbird Depth Finder

How to Use a 797 SI Humminbird Depth Finder
The Humminbird 797 SI is a combination side-imaging depth finder, GPS chart plotter and dual beam sonar unit. A full color TFT screen, sonar depth reading to 1500 feet, side-image depth reading to 150 feet and internal memory for up to 3000 GPS waypoint markings come with the unit. A transom mount kit and transducer installation package comes with the depth finder. The depth finder provides 180 degree readings under the boat.


Difficulty: Moderately Easy

Start Up Menu

Step 1
Push the power button "On." Allow the unit's display to come up and begin pulling in sonar, side-image readings and GPS signals. The screen will go to the default sonar display. Look for the number in the upper left hand corner. This number is the depth, in feet, of the lake or body of water underneath the boat.
Step 2
Put the boat into motion and watch the display screen begin to change. In the middle left hand side of the display, read the speed reading (in miles per hour) and the depth reading. These will change as the bottom of the lake changes and the boat increases or decreases in speed.
Step 3
Look for small colored bundles of pixels on the display. These are schools of bait fish. Humminbird recommends using these bait fish schools as good areas to fish for larger species. Watch the display for blue fish symbols. Fish symbols represent larger fish.
Step 4
Push the cursor control button on the screen to enlarge fish symbols. This brings up a "Zoom" button. Push once to magnify by 2x. Repeat until you reach the desired magnification. Press "Exit" to go back to the default settings, or push the "Zoom Out" button to reduce magnification by 2x each time you press the button.
Step 5
Press any arrow on the "Cursor Control" buttons to freeze the frame and view. Use this information when anchoring and getting ready to drop lines into the water. Press "Exit" to release the freeze frame view and return to the default screen display.
Step 6
Press the "Sonar Tab Button" to bring up a drop down menu. Press "Bottom View" to receive a display screen shot of the sonar readings of the lake bottom and topography. Press the "Sonar Zoom View" button to magnify the lake bottom/sonar reading by 2x for each press. Press "Exit" to return to the default screen settings.

Tips & Warnings

Print and laminate a copy of the Legend from the user manual of the depth finder. Keep this by the screen display in the boat to help read and understand display readings.

Article Written By Eric Cedric

A former Alaskan of 20 years, Eric Cedric now resides in California. He's published in "Outside" and "Backpacker" and has written a book on life in small-town Alaska, "North by Southeast." Cedric was a professional mountain guide and backcountry expedition leader for 18 years. He worked in Russia, Iceland, Greece, Turkey and Belize. Cedric attended Syracuse University and is a private pilot.

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