furuno

[kokinidis1]

hello.the big fish that is below ,why he did not read it accufish,does not show cm??

 

[C-Bass]

Good morning Kokinidis,

The fish mark on the screen did not show a accufish length like due to the fish not being in the main -3db beam of both the high and low frequency.

 

[kokinidis1]

please..you can get a better explanation..thanks.

 

[C-Bass]

Kokinidis,

Every transmit pulse has a main beam and 2nd, 3rd, beams also called side lobes. The sides lobes on many occasions can pick up fish targets on show fish targets on the screen. However the system only uses the main beam at the -3db point for the accufish measurement. So although the fish may show on the screen it may not be completely in the the main beam on both frequencies, and it has to be received in the main beam on both frequencies to get a measurement.