Radar Observer · Controls — STC (Sea Clutter)
The sensitivity time control (STC / anti-sea-clutter) reduces clutter by:
- ALengthening the transmitted pulse
- BIncreasing gain at all ranges
- CSuppressing receiver gain at short range, where sea-return is strongest, and restoring it with increasing range✓ Correct
- DTurning off the display near the center
Explanation
Sea clutter is strongest close to the ship and fades with range. STC applies reduced gain near the center, tapering back to full gain farther out, so close-in clutter is suppressed without blinding the set at long range. Over-use of STC can hide small nearby targets — adjust to just clear the clutter.
Authority: Bowditch (Pub. No. 9), Radar Controls
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