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1. ______ is not a job of the radar antenna£®

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

2. ______ is not used in modern radar£® A£®EBL B£®VRM C£®CRT

D£®Grease pencil

3. ______ typically extends from close as 0.1 nautical miles out to 32 NM£® A£®EBL B£®VRM C£®CRT

D£®target tracking range

4. Although manual plotting for CPA works well£¬the workload can become overwhelming when confronted with ______£® A£®one target B£®two targets C£®three targets

D£®a large number of targets

5. I ______ shorebased radar assistance£® A£®Ask B£®Look for C£®Require D£®In need of

6. In fog you observe your radar and determine that risk of collision exists with a vessel which is 2 miles off your port bow£®You should ______£® A£®stop your engines

B£®sound the danger signal at two-minute intervals

C£®hold course and speed until the other vessel is sighted D£®take avoiding action as soon as possible

7. My radar is not working£®I require shore based radar assistance£®Is shore based radar assistance ________? A£®used B£®available C£®in use

D£®can be used 8. PPI is ______£®

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

9. Radar makes it possible and much safer for us to sail ______£® A£®In dense fog

B£®In boisterous weather C£®In the open sea

D£®In rivers

10. Radar reflectors are required for ______£® 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

11. SWEEP INT on radar panel is the abbreviation of ______£® A£®sweep introduction B£®sweep interest C£®sweep intention D£®sweep intensity

12. The ______ has a built-in world map; most areas are displayed on a scale of 4000 nm from the top to the bottom of the screen£¬and can be zoomed in to 150 nm£® A£®chartplotter B£®C-MAP NT C£®C-Cards D£®PPI

13. The 10-cm radar as compared to a 3-cm radar of similar specifications will ______£® A£®Be more suitable for river and harbor navigation

B£®Provide better range performance on low lying targets during good weather and calm seas C£®Have a wider horizontal beam width

D£®Have more sea return during rough sea conditions

14. The articulated light is superior to other types of buoys because ______£® A£®The radar reflectors reflect better signals B£®Fog horn signals travel farther to sea C£®It is equipped with strobe lights D£®It has a reduced watch circle

15. The closest point of approach£¨CPA£©of a contact on a relative motion radar may be determined ______£® A£®Immediately when the contact is noted on radar B£®Only if the radar scope is watched constantly C£®After the contact has been marked at least twice D£®By an occasional glance at the radar

16. The correct method of switching off a marine radar is to turn power switch to ______ position first£¬then to ______ position£® A£®Off/standby B£®Standby/off C£®Standby/close D£®Close/standby

17. The development of ______ led to the fully automatic ARPA systems installed on commercial ships£® A£®SeaTalk

B£®powerful microprocessors and mega memory capacity C£®chartplotter

D£®small-scale chart

18. The radar control that reduces weak echoes out to a limited distance from the ship is the ______£® A£®sensitivity time control£¨sea-clutter control£© B£®receiver gain control C£®brilliance control

D£®fast time constant£¨differentiator£©

19. The radar control used to reduce sea return at close ranges is the ______£® A£®Gain control

B£®Sensitivity time control C£®Fast time constant D£®Pulse length control

20. The radio waves used for radar are very short£¬only ______ long£® A£®A few centimeters B£®A few fathoms C£®A few meters D£®A few feet

21. The shoreline along Rocky Point should give a good radar return because ______£® A£®The shore is bluff and rocky B£®Of offshore exposed rocks

C£®Submerged reefs cause prominent breakers

D£®The lookout tower is marked with radar reflectors

22. To determine if risk of collision exists£¬a vessel which is fitted with radar must use ______£® A£®Radar scanning B£®Radar plotting C£®Compass bearings D£®All of the above

23. What is TRUE when operating in fog and other vessels are detected by radar ________£® A£®You should make an ample change to port for a vessel crossing on the starboard bow B£®You should maneuver in ample time if a close-quarters situation is developing

C£®You should determine the course and speed of all radar contacts at six minute intervals

D£®Long-range scanning will provide early warning of ALL other vessels within the radar's range 24. What provides little or no indication that a vessel is dragging anchor ________£® A£®Increasing radar range to a fixed object ahead

B£®Drift lead with the line leading perpendicular to the centerline C£®Vibrations felt by placing a hand on the cable D£®Changing bearings to distant fixed objects abeam

25. What will cause the ARPA to emit a visual alarm£¬audible alarm£¬or both ________£® A£®An acquired target entering into a guard zone B£®A tracked target lost for one radar scan

C£®A tracked target entering your preset CPA-TCPA limits D£®A target being initially detected within a guard zone

26. When the relative motion display is selected all tracked objects will display ______ vectors£® A£®motion B£®stationary C£®dynamical D£®flashing

27. When using the ARPA in heavy rain£¬which action should you take ________£® A£®Increase the radar gain to pick up weak echoes through the rain B£®Increase the STC setting to reduce close-in spurious signals

C£®Navigate as though the effective range of the radar has been reduced D£®Increase the range of the inner and outer guard rings 28. When using the radar for navigating ______£®

A£®The best fix is obtained by using a tangent bearing and a range

B£®And using two radar ranges for a fix£¬the objects of the ranges should be close to reciprocal bearings C£®And using ranges£¬the most rapidly changing range should be measured last D£®And crossing a radar range of one object with the visual bearing of a second object£¬the two objects should be 80¡ã to 110¡ã apart

29. Which condition indicates that your radar needs maintenance ________£® A£®Serrated range rings B£®Indirect echoes C£®Multiple echoes D£®Blind sector

30. Which general statement concerning radar is FALSE ________£® A£®Raising the antenna height increases the radar range

B£®The ability of radar to detect objects is unaffected by weather conditions C£®Radar bearings are less accurate than radar ranges

D£®Radar should be checked regularly during clear weather to ensure that it is operating properly 31. Which statement concerning the operation of radar in fog is TRUE ________£® A£®Radar ranges are less accurate in fog

B£®Navigation buoys will always show up on radar

C£®A sandy beach will show up clearer on radar than a rocky cliff D£®Small wooden boats may not show up on radar

32. You are scanning the radar screen for a buoy fitted with racon£®How should this signal appear on the PPI display ________£®

A£®Starting with a dash and extending radially outward from the target B£®As a broken line from center of PPI to the target

C£®Starting with a dot and extending radially inward from the target D£®Starting with a dash and extending to the right of the target

33. You have another ship overtaking you close aboard to starboard. You have 3 radar targets bearing 090¡ã relative at ranges of 0.5 mile£¬1 mile£¬and 1.5 miles£®In this case£¬the unwanted echoes are called ______£® A£®Multiple echoes B£®Spoking

C£®Indirect echoes D£®Side-lobe echoes

34. Your ARPA has automatic speed inputs from the log£®Due to currents£¬the log is indicating a faster speed than the speed over the ground£®What should you expect under these circumstances ________£® A£®The generated CPA will be less than the actual CPA B£®The generated TCPA will be later than the actual TCPA

C£®The range of initial target acquisition will be less than normal D£®The targets true course vector will be in error

35. Your ARPA has been tracking a target and has generated the targets course and speed£®The radar did not receive a target echo on its last two scans due to the weather£®What should you expect under these circumstances ________£®

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

36. Your ARPA has two guard zones£®What is the purpose of the inner guard zone ________£® A£®Alert the watch officer that a vessel is approaching the preset CPA limit

B£®Warn of small targets that are initially detected closer than the outer guard zone C£®Guard against target loss during critical maneuvering situations D£®Sound an alarm for targets first detected within the zone

37. Your radar displays your ship off center£®As you proceed on your course, your ship's marker moves on the PPI scope while echoes from land masses remain stationary£®What is this display called ________£® A£®Off center B£®True motion C£®Stabilized D£®Head up

38. Your radar is set on a true motion display£®Which of the following will NOT appear to move across the PPI scope ________£®

A£®Echoes from a buoy B£®Own ship's marker

C£®Echo from a ship on the same course at the same speed D£®Echo from a ship on a reciprocal course at the same speed