3. FISH FINDER

This chapter is intended to help you understand how STANDARD HORIZON GPS Chart Plotters with the FF520 connected operate.

The FF520 consists of a high power transmitter, sensitive receiver and a transducer. The FF520 sends an electrical pulse to the transducer which contains a element that converts the pulse into acoustic (sound) wave which is sent through the water. As this wave travels from the transducer to the bottom, it may strike fish, structures, thermal clines (temperature changes in the water). When the wave strikes an object(s) a certain amount of the wave is reflected back to the transducer depending on the composition and shape of the object. When the reflected wave is returned to the transducer it is converted into a voltage and is amplified by the receiver, processed and sent to the display. The speed of sound in water is roughly 4800 ft./sec, so the time lapse between the transmitted signal and the received echo can be measured and the distance to the object determined.

Figure 3 - Fish Finder working principle

3.0UNDERSTANDING THE FISH FINDER PAGE

The display on STANDARD HORIZON GPS Chart Plotters shows a history of time of the echoes received by the transducer. The STANDARD HORIZON GPS Chart Plotters have a menu that allows adjustments to receiver sensitivity, depth range and scrolling speed of the Fish Finder display.

FF520

 

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Standard Horizon Ff520 owner manual Understanding the Fish Finder