Furuno 1833C Manual Do Utilizador

2. RADAR OPERATION 

 
 

The echo average feature, which requires a Model 1800/1900 series network 
radar, effectively suppresses sea clutter. Echoes received from stable targets 
such as ships appear on the screen at almost the same position during every 
rotation of the antenna. On the other hand, unstable echoes such as sea clutter 
appear at random positions. 
 
To distinguish real target echoes from sea clutter, echo average performs 
scan-to-scan correlation. Correlation is made by storing and averaging echo 
signals over successive picture frames. If an echo is solid and stable, it is 
presented in its normal intensity. Sea clutter is averaged over successive scans 
resulting in the reduced brilliance, making it easier to discriminate real targets 
from sea clutter. 
 
To properly use the echo average function, it is recommended to first suppress 
sea clutter with the A/C SEA control and then do the following: 
 
1.  If not displayed, press the [HIDE/SHOW] key to display the radar soft keys. 
2.  Press the SIGNAL PROC. soft key. 
3.  Press the E. AVG soft key to select desired echo averaging. 

OFF: No 

averaging 

LOW:  Helps distinguish targets from sea clutter and suppresses brilliance 

of unstable echoes. 

MED:  Distinguishes small stationary targets such as navigation buoys. 

HIGH:  Stably displays distant targets. 

4.  Press the RETURN soft key to finish. 
 
The display shows EAV L, EAV M or EAV H when echo averaging is on.   

(a) Echo average OFF

(b) Echo average ON