Garmin 340c Manuale Proprietario

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ETTING

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NDERSTANDING

 

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ISHFINDER

 

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ONAR

The Fishfinder 340C is a fully automatic, color sonar unit that 

allows you to go out on the water and find fish without having to 

configure a lot of settings; or, if from experience you know exactly 

how you want your Fishfinder screen to look and function, you can 

customize each setting to your specific needs and wants.
If you have used a Fishfinder before, you might already know how 

to interpret the sonar information on the screen, so you can skip 

this section. If you have not used a Fishfinder before, you might 

want to learn a bit about sonar: what it is, how it works, and what 

you might see on the Fishfinder 340C screen. This manual does not 

go into technical detail about sonar, but it can give you a general 

understanding of those things that you need to know about sonar 

that can help you interpret the screen and find the fish.

During installation, you connect your Fishfinder 340C to a 

transducer. The transducer uses sound to determine information 

about what is in the water beneath your boat. Then the transducer 

sends the information to your Fishfinder to be displayed on the 

screen for you to view and interpret. How does the transducer do 

this?

The transducer sends sound waves down into the water in a cone 

shape, similar to a flashlight beam (covering a smaller circular area 

at the top and angling out to a larger circular area at the bottom). 

These sound waves reflect off of any object that they hit, and then 

the waves travel back up to the transducer. These objects could be 

fish, branches, the bottom, or any other object that has density that 

is different from the water. The transducer receives the sound wave 

information, and then sends the information to the Fishfinder. The 

Fishfinder displays the information on the screen for you to see 

and interpret. The type of transducer and settings that you choose 

determine how the information is displayed on the screen.

Dual frequency works best for deep water (for example, off-shore) 

applications. The 200 kHz frequency allows you access to great 

detail about what is underneath your boat. The 50 kHz frequency 

provides less detailed information, but penetrates to greater depths 

with the same power. You can choose either or both frequencies to 

get the information that you want. If you choose dual frequency, 

the transducer alternates between the 50 kHz and 200 kHz signals. 

This capability allows you to see the best picture available at any 

depth.