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US Amateur Radio - Amateur Extra (Element 4, 2020-2024) Practice Test

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1. - E0A03

Over what range of frequencies are the FCC human body RF exposure limits most restrictive?

SelectAnswer
A300 kHz to 3 MHz
B300 to 3000 MHz
C30 to 300 MHz
D3 to 30 MHz

2. - E1A03

What is the maximum legal carrier frequency on the 20 meter band for transmitting USB AFSK digital signals having a 1 kHz bandwidth?

SelectAnswer
A14.070 MHz
B14.149 MHz
C14.349 MHz
D14.100 MHz

3. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

SelectAnswer
AAll amateur service frequencies authorized to the control operator
BSpecific segments in the amateur service MF, HF, VHF and UHF bands
CSpecific local government channels
DMilitary Auxiliary Radio System (MARS) channels

4. - E1C02

Which of the following types of communications may be transmitted to amateur stations in foreign countries?

SelectAnswer
AMessages intended for users of the maritime satellite service
BBusiness-related messages for non-profit organizations
CCommunications incidental to the purpose of the amateur service and remarks of a personal nature
DAll these choices are correct

5. - E1D07

Which HF amateur bands have frequencies authorized for space stations?

SelectAnswer
AAll HF bands
BOnly the 40, 20, 17, 15, 12, and 10 meter bands
COnly the 40, 30, 20, 15, 12, and 10 meter bands
DOnly the 40, 20, 17, 15, and 10 meter bands

6. - E1E06

Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

SelectAnswer
AThe FCC
BEach administering VE
CThe VEC coordinating the session
DThe VE session manager

7. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

SelectAnswer
A222 MHz - 223 MHz
B420 MHz - 430 MHz
C440 MHz - 450 MHz
D53 MHz - 54 MHz

8. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

SelectAnswer
AA linearly polarized antenna
BAn isotropic antenna
CA log-periodic dipole array
DA circularly polarized antenna

9. - E2B03

How is an interlaced scanning pattern generated in a fast-scan (NTSC) television system?

SelectAnswer
ABy scanning odd numbered lines in one field and even numbered lines in the next
BBy scanning lines from left to right in one field and right to left in the next
CBy scanning two fields simultaneously
DBy scanning each field from bottom to top

10. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of SSB or CW activity?

SelectAnswer
AIn the weak signal segment of the band, with most of the activity near the calling frequency
BAt the top of each band, usually in a segment reserved for contests
CIn the middle of each band, usually on the national calling frequency
DIn the middle of the band, usually 25 kHz above the national calling frequency

11. - E2D04

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

SelectAnswer
AAPRS
BDoppler shift of beacon signals
CBandwidth compressed LORAN
DUltrasonics

12. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

SelectAnswer
APSK31
BRTTY
CMT63
DPACTOR

13. - E3A11

What is a typical range for tropospheric propagation of microwave signals?

SelectAnswer
A2500 miles
B1200 miles
C10 miles to 50 miles
D100 miles to 300 miles

14. - E3B09

At what time of year is sporadic E propagation most likely to occur?

SelectAnswer
AAround the solstices, especially the winter solstice
BAround the equinoxes, especially the spring equinox
CAround the equinoxes, especially the fall equinox
DAround the solstices, especially the summer solstice

15. - E3C04

What does the value of Bz (B sub Z) represent?

SelectAnswer
AGeomagnetic field stability
BDuration of long-delayed echoes
CCritical frequency for vertical transmissions
DDirection and strength of the interplanetary magnetic field

16. - E4A03

Which of the following test instruments is used to display spurious signals and/or intermodulation distortion products generated by an SSB transmitter?

SelectAnswer
AA time-domain reflectometer
BA spectrum analyzer
CA logic analyzer
DA wattmeter

17. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

SelectAnswer
ADecade divider accuracy
BInput attenuator accuracy
CTime base accuracy
DTemperature coefficient of the logic

18. - E4C10

What is an advantage of having a variety of receiver IF bandwidths from which to select?

SelectAnswer
AReceive bandwidth can be set to match the modulation bandwidth, maximizing signal-to-noise ratio and minimizing interference
BThe noise figure of the RF amplifier can be adjusted to match the modulation type, thus increasing receiver sensitivity
CMultiple frequencies can be received simultaneously if desired
DReceiver power consumption can be reduced when wider bandwidth is not required

19. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

SelectAnswer
AUtilizing a Class C final amplifier
BA properly terminated circulator at the output of the repeater's transmitter
CUtilizing a Class D final amplifier
DA band-pass filter in the feed line between the transmitter and receiver

20. - E4E08

What current flows equally on all conductors of an unshielded multi-conductor cable?

SelectAnswer
ADifferential-mode current
BCommon-mode current
CReactive current only
DReturn current

21. - E5A04

What is the magnitude of the impedance of a parallel RLC circuit at resonance?

SelectAnswer
AApproximately equal to inductive reactance
BApproximately equal to circuit resistance
CLow compared to the circuit resistance
DHigh compared to the circuit resistance

22. - E5B04

What is the time constant of a circuit having two 220-microfarad capacitors and two 1-megohm resistors, all in parallel?

SelectAnswer
A440 seconds
B220 seconds
C55 seconds
D110 seconds

23. - E5C09

When using rectangular coordinates to graph the impedance of a circuit, what do the axes represent?

SelectAnswer
AThe X axis represents the resistive component and the Y axis represents the reactive component
BThe X axis represents the phase angle and the Y axis represents the magnitude
CThe X axis represents the magnitude and the Y axis represents the phase angle
DThe X axis represents the reactive component and the Y axis represents the resistive component

24. - E5D06

In what direction is the magnetic field oriented about a conductor in relation to the direction of electron flow?

SelectAnswer
AIn the same direction as the current
BIn a direction opposite to the current
CIn all directions; omni-directional
DIn a circle around the conductor

25. - E6A02

Which of the following semiconductor materials contains excess free electrons?

SelectAnswer
AN-type
BInsulated gate
CP-type
DBipolar

26. - E6B10

In Figure E6-2, what is the schematic symbol for a light-emitting diode?

SelectAnswer
A1
B7
C6
D5

27. - E6C09

What is a Programmable Logic Device (PLD)?

SelectAnswer
AProgrammable equipment used for testing digital logic integrated circuits
BA logic circuit that can be modified during use
CA programmable collection of logic gates and circuits in a single integrated circuit
DA type of transistor whose gain can be changed by digital logic circuits

28. - E6D03

Which of the following is an aspect of the piezoelectric effect?

SelectAnswer
AMechanical deformation of material by the application of a voltage
BIncreased conductivity in the presence of light
CMechanical deformation of material by the application of a magnetic field
DGeneration of electrical energy in the presence of light

29. - E6E12

Why are DIP through-hole package ICs not typically used at UHF and higher frequencies?

SelectAnswer
AUnsuitable for combining analog and digital signals
BEpoxy coating is conductive above 300 MHz
CExcessive lead length
DToo many pins

30. - E6F06

Which of these materials is most commonly used to create photoconductive devices?

SelectAnswer
AAn ordinary metal
BA heavy metal
CA crystalline semiconductor
DA liquid semiconductor

31. - E7A04

How many flip-flops are required to divide a signal frequency by 4?

SelectAnswer
A8
B4
C1
D2

32. - E7B06

Which of the following amplifier types reduces even-order harmonics?

SelectAnswer
AClass AB
BClass C
CPush-pull
DPush-push

33. - E7C01

How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network's input and output?

SelectAnswer
ATwo capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
BTwo inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground
CA capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between input and output
DAn inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output

34. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

SelectAnswer
AA series regulator
BA series current source
CA shunt regulator
DA shunt current source

35. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

SelectAnswer
AA heterodyne suppressor
BA de-emphasis network
CA heterodyne enhancer
DA pre-emphasis network

36. - E7F13

What is the function of taps in a digital signal processing filter?

SelectAnswer
AProvide access for debugging software
BProvide incremental signal delays for filter algorithms
CTo reduce excess signal pressure levels
DSelect the point at which baseband signals are generated

37. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

SelectAnswer
AIt decreases linearly with increasing frequency
BIt decreases logarithmically with increasing frequency
CIt does not vary with frequency
DIt increases linearly with increasing frequency

38. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

SelectAnswer
APierce and Zener
BArmstrong and deForest
CColpitts and Hartley
DNegative feedback and balanced feedback

39. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

SelectAnswer
A1 to 1
B25 to 1
C100 to 1
D2.5 to 1

40. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

SelectAnswer
A3
B6000
C2000
D1/3

41. - E8C09

Which digital code allows only one bit to change between sequential code values?

SelectAnswer
AExtended Binary Coded Decimal Interchange Code
BExcess 3 code
CBinary Coded Decimal Code
DGray code

42. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

SelectAnswer
AThe generation of RF harmonics
BLimits data speed
CMore difficult to copy
DThe generation of key clicks

43. - E9A05

What is included in the total resistance of an antenna system?

SelectAnswer
ARadiation resistance plus space impedance
BRadiation resistance plus transmission resistance
CTransmission-line resistance plus radiation resistance
DRadiation resistance plus loss resistance

44. - E9B10

What is the principle of a Method of Moments analysis?

SelectAnswer
AA wire is modeled as a series of segments, each having a uniform value of current
BA wire is modeled as a single sine-wave current generator
CA wire is modeled as a series of segments, each having a distinct value of voltage across it
DA wire is modeled as a single sine-wave voltage source

45. - E9C04

What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

SelectAnswer
AThe lobes align more in the direction of the wire
BThe vertical angle increases
CThe lobes become more perpendicular to the wire
DThe front-to-back ratio decreases

46. - E9D01

How much does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

SelectAnswer
A4 dB
B2 dB
C6 dB
D3 dB

47. - E9E10

Which of these choices is an effective way to match an antenna with a 100-ohm feed point impedance to a 50-ohm coaxial cable feed line?

SelectAnswer
AConnect a 1/2 wavelength shorted stub of 75-ohm cable in parallel with the 50-ohm cable where it attaches to the antenna
BConnect a 1/4-wavelength open stub of 300-ohm twinlead in parallel with the coaxial feed line where it connects to the antenna
CInsert a 1/4-wavelength piece of 75-ohm coaxial cable transmission line in series between the antenna terminals and the 50-ohm feed cable
DInsert a 1/2 wavelength piece of 300-ohm twinlead in series between the antenna terminals and the 50-ohm feed cable

48. - E9F07

How does ladder line compare to small-diameter coaxial cable such as RG-58 at 50 MHz?

SelectAnswer
ALower velocity factor
BHigher SWR
CSmaller reflection coefficient
DLower loss

49. - E9G05

Which of the following is a common use for a Smith chart?

SelectAnswer
ADetermine the length and position of an impedance matching stub
BDetermine the loss/100 feet of a transmission line, given the velocity factor and conductor materials
CDetermine the gain of an antenna given the physical and electrical parameters
DDetermine the impedance of a transmission line, given the physical dimensions

50. - E9H11

What feature of a cardioid pattern antenna makes it useful for direction finding?

SelectAnswer
AA very sharp peak
BHigh radiation angle
CBroadband response
DA very sharp single null

Figure E6-2