Anti-clutter gain control
Alternative term: Swept gain, Gain time control (Gcentre of gravity.TTime periodroll periodTransmissivity.CContrastCelsius (previously Centigrade)Capacitance.) (deprecated), Anti-clutter sea, Sensitivity time control (SSouth.TTime periodroll periodTransmissivity.CContrastCelsius (previously Centigrade)Capacitance.) (U.SSouth.Aampere.)
A device which automatically, and in a predetermined manner, increases the gain of a radar set from a low level to the maximum, within a certain period after each transmitter pulse, so that short range echoes which may be unwanted are amplified less than long range echoes.
Reference: BCentre of buoyancy.SSouth. (modified)
Please note that this is the term as it stands in the original IALAInternational Association of Marine Aids to Navigation and Lighthouse Authorities - AISM Dictionary edition (1970-1989)