How to Operate a Fish Finder

How to Operate a Fish Finder
Fish finders operate with sonar technology to bounce sound waves off the bottom of lakes and rivers, a bay or ocean. The sound wave travels back to the fish finder through a device called a transducer, which transmits data to a monitor mounted on the dashboard of a boat. The monitor transforms and displays the data as numbers and icons to represent fish, water depth, and to provide an underwater image of what's happening beneath the boat. Using a fish finder effectively takes a bit of practice. Read on to learn how these electronic devices can improve your catch.


Difficulty: Moderately Easy

Things You’ll Need:
  • Fish finder installed on a boat
Step 1
Switch on the fish finder to activate automatic mode, which is the default setting when you turn on the device.
Step 2
Take a depth reading, then switch the fish finder to manual so you can play with the controls and make adjustments.
Step 3
Adjust the sensitivity knob to about 75% to 85%. if the sensitivity is set too low, you'll get no readings. Too high, and you'll be looking at every little piece of trash and junk that floats beneath.
Step 4
Study the icons in the owner's manual and match them up with what you see on the monitor to familiarize yourself with the fish finder's display capabilities.
Step 5
Turn on the audio feature if your fish finder is equipped with sound. This will help you quickly identify different objects under the vessel when used with the information displayed on the monitor.
Step 6
If your unit is equipped with GPS, you can input the coordinates and store them in the fish finder's memory. That way, you can navigate back to productive fishing spots again and again.
Step 7
Reduce interference by turning on the suppressor feature and adjusting to a level that minimizes radio interference with the fish finder. See Tips section for additional information on suppressing interference.

Tips & Warnings

If you are getting bizarre or obviously incorrect monitor readings, such as the Loch Ness Monster lurking below the boat, you may have noise, vibration or radio interference messing with the fish finder. Turn off other electronic devices on the vessel such as the windglass defroster and the radio. If that doesn't help, try moving the transducer farther from the outboard motor or adjust the transducer by turning it in a different direction.

Article Written By James Clark

James Clark began his career in 1985. He has written about electronics, appliance repair and outdoor topics for a variety of publications and websites. He has more than four years of experience in appliance and electrical repairs. Clark holds a bachelor's degree in political science.

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