航海英语雷达及ARPA的使用章节练习(2017.09.27)

A.She must use this equipment to obtain early warning of risk of collision
B.The use of a radar excuses a vessel from the need of a look-out
C.The radar equipment is only required to be used in restricted visibility
D.The safe speed of such a vessel will likely be greater than that of vessels without radar

A.To receive the high-frequency pulses from the transmitter
B.To focus the pulses into a beam，and send them into space
C.To pick up reflected pulses coming from objects that have been struck by the beam
D.To reflect microwaves

A.sensitivity time control (sea-clutter control)
B.receiver gain control
C.brilliance control
D.fast time constant (differentiator)

A.one target
B.two targets
C.three targets
D.a large number of targets

A.station the look-out in the wheelhouse to keep a continuous watch on the radar
B.secure the sounding of fog signals until a vessel closes within five miles
C.station a look-out as low down and far forward as possible
D.keep the radar on the shortest available range for early detection of approaching vessels

A.a plan-position indicator system
B.pulse-plan integration
C.pulse-pulse input
D.power-plan input

A.all fishing vessels over 39 feet in length
B.sail-propelled fishing vessels
C.all fishing vessels of less than 200 GT
D.wooden hull fishing vessels with a poor radar echo

A.The ARPA will generate data as if the target was still being tracked by radar
B.The ARPA will give an audible and/or visual lost target alarm
C.The ARPA will generate data based on sea return echoes from the vicinity where the target was lost
D.The ARPA has lost all memory of the target and must recompute the target data

A.Immediately after floating free
B.After about one hour when the salt water activates the battery
C.Only when keyed by the radar of another vessel
D.Only when daylight activates the photovoltaic cell

A.Off center
B.True motion
C.Stabilized
D.Head up