How do I Understand Fish Finders?

Strong winds can affect the signal quality of your fish finder.

A fish finder is a tool for fishing which uses sonar technology developed during World War II to locate fish and other objects beneath the water. This eliminates some of the guesswork of the sport and may help you improve your catches.

How It Works

A fish finder works by sending a sonar signal into the water. This signal is a narrow sound wave or "beam" which widens as it travels. When the beam encounters a fish, it will bounce back to your finder, which can then calculate the time elapsed between sending and receiving the signal, allowing it to figure out the distance to the fish.

Reading the Display

Your fish finder displays a fish-shaped signal when it encounters a fish. Using a special technology, the fish finder can determine not only the distance, but also the shape of the object it finds and decide whether it is a fish. The fish finder can also display a thermocline, or a change in temperature of the water, using a line symbol. This is useful because certain fish prefer colder waters.

The Transducer

The transducer is responsible for translating signals from your fish finder console into sonar waves and back into readable information. You should mount the transducer so that it rests in the water, but keep it far enough away from motors so that it does not get damaged.

References

• Fishfinder Store: How a Fish Finder Works