3.12.1 Suitable means should be provided for the
suppression of unwanted echoes from sea clutter, rain and other forms
of precipitation, clouds, standstorms and from other radars. It should
be possible to adjust manually and continuously the anti-cluster controls.
In addition, automatic anti-clutter controls may be provided; however,
they should be capable of being switched off.
3.12.2 The operational requirement, which the
radar antenna is mounted at a height of 15 m above sea level, is that
the equipment should, even in the presence of sea clutter, give a
clear indication of a standard reflector up to 3.5 nautical miles.