How to Use a Circular Flasher Fishfinder

How to Use a Circular Flasher Fishfinder
Fish and depth finders operate using either analog or digital signal receivers designed to interpret sonar image waves transmitted via a transducer fixed to the bottom of the boat. Many units using the flasher function are analog--and a bit antiquated. Circular flasher units have a function allowing for an almost instantaneous circular visual readout on the display screen of the depth and obstacles or fish under the boat. The use of this function is fairly standard between makes and models equipped with the flash capability.


Difficulty: Moderately Easy

Step 1
Select the "Full Screen" or "Main Menu" option on your unit using the cursor control buttons. Look at the display for large black numbers in either corner. This number is the depth of the water represented in default feet (for United States models). Other display items will include water temperature, boat speed and lake bottom topography.
Step 2
Select "Split Screen" or the equivalent for your particular unit. Wait for the dual displays to appear on the main screen of the unit. One side of the screen will display the full sonar imaging, and the other displays a sonar image screen you can zoom in or out. Zoom in by pressing the "Zoom" function with your cursor controls.
Step 3
Choose the "Split Frequency" option from the drop-down menu if your unit is equipped with this function. The unit will now receive and display sonar imaging received from the transducer on 50 MHz to 200 MHz. Using the dual frequency gives two distinct visual representations of the sonar waves' received signals, allowing you to decipher between screen pixelation and actual obstacles.
Step 4
Select "Flasher" from the drop-down menu. Look at the display to see an almost instant image of the water and contents under the boat for the unit's depth capabilities. The display appears as a circle and will display for a few seconds. Continue to select the Flasher for updates on obstacles, fish and water bottom when you are over your desired location.

Tips & Warnings

Use the Flasher function as a quick reference to use against the static screens. Flasher displays show real-time fish movement, helping you decide what you are seeing under the boat with the display screens.

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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