Adjusting the A/C SEA control
The proper setting of the A/C SEA should be such that the clutter is broken up into small dots, and small targets become distinguishable.
If the control is set too low, targets will be hid- den in the clutter, while if it is set too high, both sea clutter and targets will disappear from the display. In most cases adjust the control until clutter has disappeared to leeward, but a little is still visible windward.
1.Confirm that the sensitivity is properly ad- justed, and then transmit on short range.
2.Adjust the [A/C SEA] control so small tar- gets are distinguishable but some clutter re- mains on the display.
2.10Adjusting the A/C RAIN Control
(reducing rain clutter)
The vertical beamwidth of the antenna is de- signed to see surface targets even when the ship is rolling. However, by this design the unit will also detect rain clutter (rain, snow, hail, etc.) in the same manner as normal targets. Figure
Adjusting A/C RAIN
When rain clutter masks echoes, adjust the [A/ C RAIN] control. This control splits up these unwanted echoes into a speckled pattern, mak- ing recognition of solid targets easier.
Sea clutter at | A/C SEA control adjusted; |
display center | sea clutter suppressed. |
Figure 2-4 How to adjust the A/C SEA control
Tip for adjusting the A/C SEA
A common mistake is to
CAUTION
Turn off the A/C SEA control when its use is not required; the control can erase weak targets.
Appearance of | A/C RAIN control adjusted; |
rain clutter | rain clutter suppressed. |
Figure 2-5 Effect of A/C RAIN
Note: In addition to reducing clutter, the [A/C RAIN] control can be used in fine weather to clarify the picture when navi gating in confined waters. However, with the circuit activated the receiver is less sensitive. Therefore, turn off the circuit when its function is not required.
Automatic adjustments of A/C SEA and A/C RAIN
Push the [A/C SEA (A/C AUTO)] control. “A/ C AUTO” appears at the bottom