Ground Radar 3d155
EOR For ground radar 3D135
- 1.
When a pulse of radio frequency energy is transmitted, it travels at
- A.
The speed of light
- B.
The speed of sound
- C.
One-half the speed of light
- D.
One-half the speed of sound
Correct Answer
A. The speed of light -
- 2.
What is the required angle of incidence necesary to get a reflection back to a light source?
- A.
A. 45.
- B.
b. 90.
- C.
C. 135.
- D.
D. 180
Correct Answer
B. b. 90. -
- 3.
Approximately how long does it take for radio frequency energy to travel 1 nautical mile to a target and return to the radar?
- A.
A. 3.09 ƒÝs.
- B.
B. 6.18 ƒÝs.
- C.
C. 9.27 ƒÝs.
- D.
D. 12.36 ƒÝs.
Correct Answer
D. D. 12.36 ƒÝs. -
- 4.
You can identify the maximum detection range of a radar by dividing the time of one radar mile into the
- A.
A. transmitter on-time.
- B.
B. transmitter off-time.
- C.
C. pulse recurrence time.
- D.
D. pulse repetition frequency.
Correct Answer
C. C. pulse recurrence time. -
- 5.
What characteristic of frequency does a radar target moving towards the radar exhibit?
- A.
A. A lower frequency than the original broadcast.
- B.
B. A higher frequency than the original broadcast.
- C.
C. No apparent frequency change than the original broadcastb||Œ
- D.
D. Oscillating lower and higher frequency changes in respect to the original broadcast._
Correct Answer
B. B. A higher frequency than the original broadcast. -
- 6.
Which radar subassembly ensures all circuits connected with the radar operate in a definite timed relationship?
- A.
A. Synchronizer.
- B.
B. Transmitter..
- C.
C. Modulator.r..
- D.
D. Duplexer..r..
Correct Answer
A. A. Synchronizer. -
- 7.
What radar subassembly allows the radar system to transmit and receive from the same antenna?
- A.
A. Synchronizer.
- B.
B. Transmitter..
- C.
C. Modulator.r..
- D.
D. Duplexerr.r..
Correct Answer
D. D. Duplexerr.r.. -
- 8.
An antenna is said to be reciprocal if
- A.
A. it is nonlinear.
- B.
B. it transmits patterns.ency.
- C.
C. it contains ferrite devices.
- D.
D. its transmit and receive patterns are identical.
Correct Answer
D. D. its transmit and receive patterns are identical. -
- 9.
Which feedhorn is used only for receiving?
- A.
A. Active
- B.
B. Linear
- C.
C. Passive
- D.
D. Circular
Correct Answer
C. C. Passive -
- 10.
One use for the beam-lobing switch of the multi-feedhorn system is to
- A.
A. raise the effective beam coverage by 3.
- B.
B. dummy load the lower 3„a of the transmitted beam.LT
- C.
C. route the received signal from the number one feedhorn to a dummy load.b
- D.
D. vary low-level coverage by routing more radio frequency through one feedhorn.
Correct Answer
C. C. route the received signal from the number one feedhorn to a dummy load.b -
- 11.
What does the distribution of electromagnetic energy from the antenna over the aperture determine?
- A.
A. Main lobe gain.
- B.
B. Pattern of the antenna.ices.
- C.
C. Probability of interference.
- D.
D. Susceptibility of the antenna.
Correct Answer
B. B. Pattern of the antenna.ices. -
- 12.
The shape of the beam of radar energy and its antenna pattern depend on the radar’s
- A.
A. gain.
- B.
B. location
- C.
C. purpose
- D.
D. power
Correct Answer
C. C. purpose -
- 13.
The scanning method used by the radar system refers to the
- A.
A. direction of energy into an appropriately shaped beam
- B.
B. orientation of the electromagnetic wave as it travels through space.
- C.
C. motion of the antenna axis (of the beam) as the radar looks for an aircraftˆÊ
- D.
D. efficient launch and reception of electromagnetic energy in the atmosphere or space
Correct Answer
C. C. motion of the antenna axis (of the beam) as the radar looks for an aircraftˆÊ -
- 14.
What scan is identified at the electronic countermeasure receiver by its regular intervals between illuminations?
- A.
A. Raster
- B.
B. Conical
- C.
C. Circular
- D.
D. Monopulse
Correct Answer
C. C. Circular -
- 15.
What scan system uses a thin beam to cover a rectangular area by sweeping the area horizontally with the angle of elevation incrementally stepped up or down with each horizontal sweep of the sector?
- A.
A. Raster
- B.
B. Conical
- C.
C. Circular
- D.
D. Monopulse
Correct Answer
A. A. Raster -
- 16.
Which scan radar is also used in the acquisition phase by some airborne intercept radars?
- A.
A. Raster
- B.
B. Conical
- C.
C. Circular
- D.
D. Monopulse
Correct Answer
A. A. Raster -
- 17.
Which scan radar gets its name from the fact that each echo pulse from the aircraft being tracked yields a new azimuth and elevation correction signal?
- A.
A. Raster
- B.
B. Conical
- C.
C. Circular
- D.
D. Monopulse
Correct Answer
D. D. Monopulse -
- 18.
In which scan radar does the antenna rotate on an azimuth sweep, while the elevation angle rises slowly from 0 to 90?
- A.
A. Palmer
- B.
B. Helical
- C.
C. Palmer/Raster
- D.
D. Track-While
Correct Answer
B. B. Helical -
- 19.
What causes delayed, but separate, pulses?
- A.
A. Simultaneous reception of pulse-type information
- B.
B. Near-simultaneous reception of pulse-type information
- C.
C. Electromagnetic (EM) waves reach the receiving antenna by direct paths
- D.
D. EM waves reach the receiving antenna by indirect paths
Correct Answer
B. B. Near-simultaneous reception of pulse-type information -
- 20.
Attempts to reduce multipath effects on radar tracking accuracy include the use of
- A.
A. off-axis tracking.
- B.
B. frequency agility.
- C.
C. monopulse radar.
- D.
D. off-boresight tracking
Correct Answer
B. B. frequency agility. -
- 21.
What type of radar system uses a B-scan indicator?a. Long-range surveillance.
- A.
A. Long-range surveillance
- B.
B. Airport surveillance.
- C.
C. Precision approach
- D.
D. Weather
Correct Answer
C. C. Precision approach -
- 22.
What target information is provided by a plan-position indicator?
- A.
A. Azimuth only.
- B.
B. Elevation only
- C.
C. Range and azimuth
- D.
D. Elevation and range
Correct Answer
C. C. Range and azimuth -
- 23.
In a Raster scan indicator, how many vertical scan periods does it take to produce one complete picture?
- A.
A. 1
- B.
B. 2
- C.
C. 3
- D.
D. 4
Correct Answer
B. B. 2 -
- 24.
Which indicator component produces signals that determine the overall operation of what the indicator will do?
- A.
A. Data processing circuits
- B.
B. Deflection circuits..
- C.
C. Cathode-ray tube
- D.
D. Video circuits.
Correct Answer
A. A. Data processing circuits -
- 25.
In a typical indicator system, where is digital display data from the data processing circuits converted into analog drive signals
- A.
A. Deflection circuits..
- B.
B. Cathode-ray tube
- C.
C. Video circuits.
- D.
D. Power supply.
Correct Answer
A. A. Deflection circuits.. -
- 26.
The vacuum in a cathode-ray tube (CRT)
- A.
A. prevents implosion if the CRT is broken.
- B.
B. keeps the phosphor coating from burning.
- C.
C. eliminates static charges on the deflection plates.
- D.
D. prevents collisions between electrons in the beam and air molecules
Correct Answer
D. D. prevents collisions between electrons in the beam and air molecules -
- 27.
What frequency is used for identification friend or foe/selective identification feature (IFF/SIF) interrogations?
- A.
A. 1030 MHz
- B.
B. 1070 MHz
- C.
C. 1090 MHz
- D.
D. 1270 MHz
Correct Answer
A. A. 1030 MHz -
- 28.
An X pulse is present in a selective identification feature code train when
- A.
A. a Mode 4 reply is being received.
- B.
B. the aircraft is a pilotless drone or missile.
- C.
C. the aircraft is declaring a military emergency
- D.
D. it is requested by the radar operator to identify the aircraft position.
Correct Answer
B. B. the aircraft is a pilotless drone or missile. -
- 29.
Which selective identification feature special response explains a 7500 reply?
- A.
A. Communication failure
- B.
B. Military emergency.
- C.
C. Engine failure.
- D.
D. Hijacking
Correct Answer
D. D. Hijacking -
- 30.
What is the AN/UPM–155 radar test set capable of testing?
- A.
A. Interrogators and associated components.
- B.
B. Radar antenna orientationce.
- C.
C. Radar jamming strengthionce.
- D.
D. Radar receivers
Correct Answer
A. A. Interrogators and associated components. -
- 31.
What possible input voltage(s) may be supplied to the AN/UPM–155 radar test set for operation?
- A.
A. 115 Vac
- B.
B. 120 Vac
- C.
C. 230 vac
- D.
D. 115 Vac or 230 Vac
Correct Answer
D. D. 115 Vac or 230 Vac -
- 32.
What element of modulation prevents interference when sharing the same communications path is necessary?
- A.
A. Spectrum conservation
- B.
B. Channel allocation
- C.
C. Ease of radiation
- D.
D. Companding
Correct Answer
B. B. Channel allocation -
- 33.
What factor determines the spacing of the sidebands in an amplitude modulated signal?
- A.
A. Amplitude of the modulating signal
- B.
B. Frequency of the modulating signal
- C.
C. Amplitude of the carrier signal
- D.
D. Frequency of the carrier signal
Correct Answer
B. B. Frequency of the modulating signal -
- 34.
What is the relationship of the bandwidth required for double-sideband emitted carrier (DSBEC) amplitude modulation (AM) to the bandwidth of the modulating signal of the AM bandwidth alone?
- A.
A. One-quarter of the modulating bandwidth
- B.
B. Four times the modulating bandwidth.i
- C.
C. Twice the modulating bandwidth.
- D.
D. Half the modulating bandwidth
Correct Answer
C. C. Twice the modulating bandwidth. -
- 35.
In frequency modulation, the amount of oscillator frequency change is
- A.
A. inversely proportional to the amplitude of the modulating signal.s
- B.
B. directly proportional to the amplitude of the modulating signal.
- C.
C. inversely proportional to the phase of the modulating signal.
- D.
D. directly proportional to the phase of the modulating signal.
Correct Answer
B. B. directly proportional to the amplitude of the modulating signal. -
- 36.
A 10 kHz modulating signal has enough peak voltage to cause a deviation of 30 kHz. What is the modulation index?ceiveCo
- A.
A. 5
- B.
B. 0.5
- C.
C. 0.3
- D.
D. 3
Correct Answer
D. D. 3 -
- 37.
In phase modulation, the carrier’s
- A.
A. phase shifts at the rate of the modulating signal.
- B.
B. phase shifts with the phase of the modulating signal
- C.
C. amplitude shifts at the rate of the modulating signal
- D.
D. amplitude shifts with the phase of the modulating signal
Correct Answer
A. A. phase shifts at the rate of the modulating signal. -
- 38.
Information capacity is increased by how many times its normal rate if using 8– phase shift keying (PSK) instead of binary PSK?
- A.
A. two
- B.
B. three
- C.
C. four
- D.
D. five
Correct Answer
B. B. three -
- 39.
What size bit combinations are allowed when using 16–phase shift keying?
- A.
A. 2 bit
- B.
B. 3 bit
- C.
C. 4 bit
- D.
D. 5 bit
Correct Answer
B. B. 3 bit -
- 40.
What part of the pulse code modulation process converts a continuous time signal into a discrete time signal?.
- A.
A. Sampling
- B.
B. Rectifying
- C.
C. Oscillating
- D.
D. Band Limiting
Correct Answer
A. A. Sampling -
- 41.
By how much does non-uniform quantizing and companding decreases the length of a code word?]
- A.
A. 11 to 7 bits.
- B.
B. 11 to 8 bits.
- C.
C. 16 to 7 bits.
- D.
D. 16 to 8 bits.
Correct Answer
A. A. 11 to 7 bits. -
- 42.
How is the parity bit used in asynchronous transmission?
- A.
A. By the receiving device to verify that the transmission was received correctly.
- B.
B. By the transmitting device to verify that the transmission was transmitted correctly.
- C.
C. By the modulator device to verify that the intelligence signal was received correctly
- D.
D. By the band limiting device to verify that the output signal was transmitted correctly
Correct Answer
A. A. By the receiving device to verify that the transmission was received correctly. -
- 43.
How does synchronous transmission reduce the overhead costs of data transmission?
- A.
A. Communicates in parallel format.
- B.
B. Blocks many characters together for transmission
- C.
C. Eliminates the control bits, so more message data can be sent.
- D.
D. Uses low cost equipment to support synchronous transmission.
Correct Answer
B. B. Blocks many characters together for transmission -
- 44.
During a vertical redundancy check, what significance does the amount of 1’s have in a data bit pattern?
- A.
A. Determines parity.
- B.
B. Determines transmission rate.
- C.
C. Determines whether transmission is in ASCII format
- D.
D. Determines whether transmission is synchronous or asynchronous
Correct Answer
A. A. Determines parity. -
- 45.
Using the longitudinal redundancy check method of error correction, what does the receiver compare with the transmitter to ensure an accurate transmission of data??
- A.
A. The checksum.
- B.
B. Block check character.
- C.
C. The ASCII character set.
- D.
D. The sum of transmitted bits.
Correct Answer
B. B. Block check character. -
- 46.
When used together, what two error detection methods are 98 percent effective in detecting errors?
- A.
A. Checksum and cyclic redundancy check.
- B.
B. Longitudinal redundancy check and checksum.
- C.
C. Cyclic redundancy check and vertical redundancy check.
- D.
D. Vertical redundancy check and longitudinal redundancy check.
Correct Answer
D. D. Vertical redundancy check and longitudinal redundancy check. -
- 47.
What error detection method is used for checking a data block greater than 512 and is about 99 percent effective in most applications?
- A.
A. Checksum.
- B.
B. Cyclic redundancy.
- C.
C. Vertical redundancy.
- D.
D. Longitudinal redundancy.
Correct Answer
B. B. Cyclic redundancy. -
- 48.
When using forward error control as a method of error correction, where does error correction take place?
- A.
A. Receiving end.
- B.
B. In the oscillator.
- C.
C. Transmitting end
- D.
D. In the primary buffers
Correct Answer
A. A. Receiving end. -
- 49.
Which statement describes an advantage of using fiber optic cable?
- A.
A. The easy tap-ability of fiber optic cables reduces security risks.®x
- B.
B. Fiber optic cable has a higher attenuation than coaxial cable
- C.
C. Electromagnetic fields do not affect fiber optic cables.
- D.
D. Nuclear radiation does not affect fiber optic cable.
Correct Answer
C. C. Electromagnetic fields do not affect fiber optic cables. -
- 50.
Which statement describes a security feature of using fiber optic cable?
- A.
A. Easy to encrypt data.
- B.
B. Low signal attenuation.
- C.
C. Virtually impossible to tap a fiber optic cable unnoticed.Nã
- D.
D. Fiber optic cables are considerably smaller than metallic cable
Correct Answer
C. C. Virtually impossible to tap a fiber optic cable unnoticed.Nã -
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May 14, 2016Quiz Edited by
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Aug 30, 2012Quiz Created by
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