Other radar controls

Range selector position. The range selector is used to select the range that the radar will cover. There are five positions, indicated in miles: 1½, 3, 6, 12, and 24 miles. When the range is selected, the distance between the rings is determined automatically.
Brilliance control. By using this control, the background illumination of the screen can be adjusted. This allows better visibility of amplified echoes and noises appearing on the screen.
Tuning control. This control allows the receiver to be tuned to the same frequency as the transmitter.
Tuning indicator. This is a visual electronic aid that helps to tune the radar quickly and accurately. Adjustment of the knob to display the narrowest gap corresponds to optimum tuning.
Gain control. This control allows the user to vary the strength of echoes appearing on the screen.
Anti-sea Clutter control. The main use of this control is to reduce the strength of sea clutter or echos from waves, near the ship, so strong targets e.g. small craft, buoys, etc., can be clearly distinguished. This control reduces the gain level only over a short range.
The knurled ring is used to rotate the bearing cursor over the face of the screen, which allows the user to measure the bearings of the targets.