Question 986Navigation General

70% to pass

When you turn on the fast time constant (differentiator) control of a radar it will _______________.

A reduce the beam width to provide a map-like presentation for navigation
B only suppress weak targets to a limited distance from the ship (sea clutter)
C enhance weak target echoes and brighten them on the PPI
D reduce clutter over the entire PPI by shortening the echoes
AI Explanation

The correct answer is D) reduce clutter over the entire PPI by shortening the echoes. When the fast time constant (differentiator) control is activated on a radar, it enhances the leading and trailing edges of radar echoes, effectively shortening the echoes displayed on the PPI (Plan Position Indicator). This helps to reduce clutter and improve target detection by suppressing extended echoes, such as those from sea and land, across the entire radar display. The other options are incorrect because they do not accurately describe the primary function of the fast time constant control.

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Official Resources
USCG Navigation Rules (COLREGS) 33 CFR Navigation Rules USCG National Maritime Center
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