Errors and set up in radar and ARPA

What is the typical accuracy for range measurements under normal conditions in marine radar?

• ±1 meter

• ±10 meters

• ±30 meters

• ±100 meters

Which of the following is a cause of bearing errors in marine radar?

• Incorrect range scale alignment

• Sweep timing inaccuracies

• A wide beam

• Longer pulses

What type of radar error is caused by wave returns masking small targets?

• Side-lobe echoes

• Multiple echoes

• Sea clutter

• Radar-to-radar interference

Which type of radar is generally preferred for long-range detection in open sea and heavy weather conditions?

• X-band radar

• S-band radar

• Both X-band and S-band equally

• Neither, as radar is ineffective in heavy weather

Which of the following statements accurately describes a RACON (Radar Beacon)?

• It provides bearing information only and transmits signals continuously.

• It responds only when interrogated by a ship's radar and provides both bearing and range information.

• It appears on the PPI as a series of dots, dashes, or a continuous line.

• Its transmission is continuous or interval-based and covers a 360-degree omnidirectional area.

What is the primary difference between a blind sector and a shadow sector on a radar display?

• A blind sector is caused by electronic interference, while a shadow sector is caused by atmospheric conditions.

• In a blind sector, targets are completely undetected, whereas in a shadow sector, targets are detected but their echoes are weakened or distorted.

• A blind sector is fixed relative to the ship's heading, while a shadow sector changes with the ship's speed.

• A blind sector only occurs in coastal waters, while a shadow sector occurs in open sea.

What is the purpose of the Sensitivity Time Control (STC) on a radar?

• To adjust the magnetron warm-up time.

• To suppress rain clutter at long ranges.

• To suppress sea clutter near the own ship at short ranges.

• To align the heading marker with visual bearings.

For collision avoidance in open sea, which radar stabilization mode is generally recommended?

• Ground stabilized mode, as it shows true land-relative tracks.

• Sea stabilized mode, as it correctly shows relative motion with respect to surrounding vessels.

• A combination of both modes, switching frequently.

• Neither, as radar is not suitable for collision avoidance.