Navigatie partea 2 300 intrebari

In restricted visibility, risk of collision can best be assessed by....

• posting additional lookouts

• watching the target's radar bearing and range

• establishing radio communication with the target

• listening for the target's sound signals

In what type of waveform does the current go from zero to maximum slowly but very steadily?

• Saw- tooth wave form

• Spike waveform

  
  

•   Square waveform

  
  

• Direct current waveform
  

Incoming target echoes are detected by the....

• video amplifier

• mixer crystal

• I.F. amplifier

• local oscillator

Indirect echoes appear on the display....

• on the true bearing, but at a false range

• on the true range, but on a false bearing

• on the true range and bearing

•   on a false range and bearing

Indirect echoes are caused by reflections from.....

• targets on the beam.

• targets directly ahead.

• the surface of the sea.

• obstructions close to the scanner.

Indirect echoes can be recognised by the fact that they....

• appear at twice the true range

• appear as lines of dots or dashes

• appear on the arc of a circle

• appear in shadow sectors

Marine radar wavelengths are measured in .....

• microseconds.

• feet per second.

• centimetres.

• megahertz.

Maximum radar range depends partly on the....

• size of the spot.

• mixer strength.

• peak power output.

• scanner rotation speed.

Minimum radar range depends mainly on......

• scanner height.

• pulse length.

• receiver sensitivity.

• vertical beamwidth.

Multiple echoes appear on the screen....

• on the correct bearing but half the true range

• on the correct range but a false bearing

• on the correct bearing at double the true range

• on a false bearing and range