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3.4  BASIC OPERATIONS
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3.4.7    Suppress Rain/Snow Clutter [AUTO-RAIN] 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 Procedures   1  Control the rain/snow clutter returns on the radar display by turning the 
[AUTO-RAIN] control until targets can be easily observed. 
 
Turning [AUTO-RAIN] control clockwise suppresses rain/snow clutter returns. 
Turning [AUTO-RAIN] control counterclockwise intensifies rain/snow clutter returns. 
 
When the [AUTO-RAIN] control is turned clockwise, the rain/snow clutter suppression 
function suppresses rain/snow clutter returns and gets targets hidden by rain/snow clutter 
returns to appear on the radar display.    However, be careful that excessive suppression may 
cause small targets to be overlooked.    Since the rain/snow clutter suppression function also 
has the effect of suppressing sea clutter, the suppression efficiency improves when the 
[AUTO-RAIN] control is used with the [AUTO-SEA] control.    In general, turn the 
[AUTO-RAIN] control fully to the left. 
Before rain/snow clutter returns can be suppressed in accordance with their intensity, the 
automatic rain/snow clutter suppression mode must be selected by pressing the 
[AUTO-RAIN] control. 
To change back to the manual mode, press the [AUTO-RAIN] control again. 
 
 
Note:  The AUTO SEA (automatic sea clutter suppression) mode and the AUTO RAIN (automatic 
rain/snow clutter suppression) mode cannot be used at the same time. 
 
 
Using AUTO RAIN (automatic rain/snow clutter suppression function): 
 
 
 Procedures   1  Press the [AUTO-RAIN] control. 
 
AUTO RAIN is selected, and RAIN    AUTO    is indicated at the lower left of the radar 
display.    Rotating the AUTO RAIN control and AUTO SEA control can make fine 
adjustments manually. 
 
 
When using the [AUTO RAIN] function, never set the 
suppression level too high canceling out all image 
noises from the rain or snow at the close range. 
Detection of not only echoes from the rain or snow but 
also targets such as other ships or dangerous objects 
will become inhibited. 
When using the [AUTO RAIN] function, make sure to 
choose the most appropriate image noise suppression 
level. 
Caution