Radar Observer · Controls — FTC (Rain Clutter)
The fast time constant (FTC / anti-rain-clutter) control:
- ADisables the heading marker
- BIncreases pulse length
- CRaises gain inside rain
- DDifferentiates the signal so only the leading edge of extended returns (like rain) is displayed, helping reveal targets within precipitation✓ Correct
Explanation
FTC shortens (differentiates) returns so that large, extended echoes such as rain are reduced to their leading edges, breaking up the solid clutter and letting discrete targets within it stand out. Like STC it can suppress weak real targets if over-applied.
Authority: Bowditch (Pub. No. 9), Radar Controls
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