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

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1. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

SelectAnswer
AIngestion of ozone gas from the cooling system
BLocalized heating of the body from RF exposure in excess of the MPE limits
CBlood clotting from the intense magnetic field
DHearing loss caused by high voltage corona discharge

2. - E1A05

What is the maximum power output permitted on the 60 meter band?

SelectAnswer
A100 watts PEP effective radiated power relative to an isotropic radiator
B100 watts PEP effective radiated power relative to the gain of a half-wave dipole
C50 watts PEP effective radiated power relative to a dipole
D50 watts PEP effective radiated power relative to an isotropic radiator

3. - E1B05

What is the National Radio Quiet Zone?

SelectAnswer
AAn area in New Mexico surrounding the White Sands Test Area
BAn area in Puerto Rico surrounding the Arecibo Radio Telescope
CAn area in Florida surrounding Cape Canaveral
DAn area surrounding the National Radio Astronomy Observatory

4. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

SelectAnswer
ACEPT agreement
BAll these choices are correct
CIARP agreement
DITU reciprocal license

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

SelectAnswer
AOnly those of General, Advanced or Amateur Extra Class operators
BAny amateur station, subject to the privileges of the class of operator license held by the control operator
CAny amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
DOnly those of Amateur Extra Class operators

6. - E1E08

To which of the following examinees may a VE not administer an examination?

SelectAnswer
AAll these choices are correct
BEmployees of the VE
CRelatives of the VE as listed in the FCC rules
DFriends of the VE

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

9. - E2B08

What technique allows commercial analog TV receivers to be used for fast-scan TV operations on the 70 cm band?

SelectAnswer
ATransmitting on channels shared with cable TV
BTransmitting on the abandoned TV channel 2
CUsing USB and demodulating the signal with a computer sound card
DUsing converted satellite TV dishes

10. - E2C04

Which of the following frequencies are sometimes used for amateur radio mesh networks?

SelectAnswer
AHF frequencies where digital communications are permitted
BThe 60 meter band channel centered on 5373 kHz
CFrequencies shared with various unlicensed wireless data services
DCable TV channels 41 through 43

11. - E2D08

What type of packet frame is used to transmit APRS beacon data?

SelectAnswer
AConnect
BDisconnect
CAcknowledgement
DUnnumbered Information

12. - E2E05

Which of these digital modes does not support keyboard-to-keyboard operation?

SelectAnswer
AMFSK
BRTTY
CPSK31
DPACTOR

13. - E3A04

What do Hepburn maps predict?

SelectAnswer
AProbability of tropospheric propagation
BLikelihood of rain scatter along cold or warm fronts
CSporadic E propagation
DLocations of auroral reflecting zones

14. - E3B01

What is transequatorial propagation?

SelectAnswer
APropagation between a point on the equator and its antipodal point
BPropagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
CPropagation between points located on the magnetic equator
DPropagation between points at the same latitude

15. - E3C06

By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

SelectAnswer
ABy approximately twice the distance
BBy approximately 15 percent of the distance
CBy approximately four times the distance
DBy approximately 50 percent of the distance

16. - E4A09

Which of the following is good practice when using an oscilloscope probe?

SelectAnswer
ANever use a high-impedance probe to measure a low-impedance circuit
BAll these choices are correct
CNever use a DC-coupled probe to measure an AC circuit
DKeep the signal ground connection of the probe as short as possible

17. - E4B08

Which of the following can be used to measure the Q of a series-tuned circuit?

SelectAnswer
AThe inductance to capacitance ratio
BThe frequency shift
CThe bandwidth of the circuit's frequency response
DThe resonant frequency of the circuit

18. - E4C12

Which of the following has the largest effect on an SDR receiver's dynamic range?

SelectAnswer
AAnti-aliasing input filter bandwidth
BCPU register width in bits
CAnalog-to-digital converter sample width in bits
DRAM speed used for data storage

19. - E4D03

How can intermodulation interference between two repeaters occur?

SelectAnswer
AWhen the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters
BWhen the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters
CWhen the signals from the transmitters are reflected in phase from airplanes passing overhead
DWhen the signals from the transmitters are reflected out of phase from airplanes passing overhead

20. - E4E01

What problem can occur when using an automatic notch filter (ANF) to remove interfering carriers while receiving CW signals?

SelectAnswer
AAny nearby signal passing through the DSP system will overwhelm the desired signal
BReceived CW signals will appear to be modulated at the DSP clock frequency
CRinging in the DSP filter will completely remove the spaces between the CW characters
DRemoval of the CW signal as well as the interfering carrier

21. - E5A12

What is the half-power bandwidth of a resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

SelectAnswer
A218.3 kHz
B15.7 kHz
C31.4 kHz
D436.6 kHz

22. - E5B03

How is impedance in polar form converted to an equivalent admittance?

SelectAnswer
ATake the square root of the magnitude and add 180 degrees to the angle
BSquare the magnitude and subtract 90 degrees from the angle
CTake the reciprocal of the angle and change the sign of the magnitude
DTake the reciprocal of the magnitude and change the sign of the angle

23. - E5C12

Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and a 19-picofarad capacitor at 21.200 MHz?

SelectAnswer
APoint 3
BPoint 8
CPoint 7
DPoint 1

24. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

SelectAnswer
AIt is dissipated as heat in the circuit
BIt is dissipated as kinetic energy in the circuit
CIt is dissipated in the formation of inductive and capacitive fields
DIt is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated

25. - E6A06

What is the beta of a bipolar junction transistor?

SelectAnswer
AThe change in collector current with respect to base current
BThe frequency at which the current gain is reduced to 0.707
CThe switching speed
DThe breakdown voltage of the base to collector junction

26. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

SelectAnswer
ALonger carrier retention time
BLess forward voltage drop
CMuch higher reverse voltage breakdown
DMore constant reverse avalanche voltage

27. - E6C03

What is tri-state logic?

SelectAnswer
AProprietary logic devices manufactured by Tri-State Devices
BLow-power logic devices designed to operate at 3 volts
CLogic devices that utilize ternary math
DLogic devices with 0, 1, and high-impedance output states

28. - E6D03

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

SelectAnswer
AMechanical deformation of material by the application of a magnetic field
BGeneration of electrical energy in the presence of light
CIncreased conductivity in the presence of light
DMechanical deformation of material by the application of a voltage

29. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

SelectAnswer
A50 ohms
B10 ohms
C300 ohms
D450 ohms

30. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

SelectAnswer
AIt decreases
BIt increases
CIt becomes unstable
DIt stays the same

31. - E7A04

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

SelectAnswer
A8
B4
C2
D1

32. - E7B07

Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?

SelectAnswer
ASignal inversion
BReduced intermodulation products
CSignal distortion and excessive bandwidth
DIncreased overall intelligibility

33. - E7C11

Which of the following describes a receiving filter's ability to reject signals occupying an adjacent channel?

SelectAnswer
ANoise factor
BShape factor
CPassband ripple
DPhase response

34. - E7D06

What is the purpose of Q1 in the circuit shown in Figure E7-2?

SelectAnswer
AIt provides a constant load for the voltage source
BIt provides negative feedback to improve regulation
CIt provides D1 with current
DIt controls the current supplied to the load

35. - E7E07

What is meant by the term "baseband" in radio communications?

SelectAnswer
AThe frequency range occupied by a message signal prior to modulation
BThe basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
CThe lowest frequency band that the transmitter or receiver covers
DThe unmodulated bandwidth of the transmitted signal

36. - E7F05

How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?

SelectAnswer
AAt least half the rate of the highest frequency component of the signal
BAt the same rate as the highest frequency component of the signal
CAt four times the rate of the highest frequency component of the signal
DAt least twice the rate of the highest frequency component of the signal

37. - E7G12

What is an operational amplifier?

SelectAnswer
AA digital audio amplifier whose characteristics are determined by components external to the amplifier
BAn amplifier used to increase the average output of frequency modulated amateur signals to the legal limit
CA high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance
DA RF amplifier used in the UHF and microwave regions

38. - E7H02

What is a microphonic?

SelectAnswer
ADistortion caused by RF pickup on the microphone cable
BExcess loading of the microphone by an oscillator
CChanges in oscillator frequency due to mechanical vibration
DAn IC used for amplifying microphone signals

39. - E8A01

What is the name of the process that shows that a square wave is made up of a sine wave plus all its odd harmonics?

SelectAnswer
AFourier analysis
BDifferential analysis
CNumerical analysis
DVector analysis

40. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

SelectAnswer
AA frequency modulation technique that uses non-harmonically related frequencies
BA digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
CA bandwidth compression technique using Fourier transforms
DA digital mode for narrow-band, slow-speed transmissions

41. - E8C02

What is the definition of symbol rate in a digital transmission?

SelectAnswer
AThe number of characters carried per second by the station-to-station link
BThe number of control characters in a message packet
CThe duration of each bit in a message sent over the air
DThe rate at which the waveform changes to convey information

42. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

SelectAnswer
ABaudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
BBaudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
CBaudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
DBaudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

43. - E9A07

What is the effective isotropic radiated power of a repeater station with 200 watts transmitter power output, 2 dB feed line loss, 2.8 dB duplexer loss, 1.2 dB circulator loss, and 7 dBi antenna gain?

SelectAnswer
A159 watts
B252 watts
C632 watts
D63.2 watts

44. - E9B06

What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

SelectAnswer
A75 degrees
B25 degrees
C7.5 degrees
D45 degrees

45. - E9C02

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

SelectAnswer
AA figure-8 end-fire along the axis of the array
BA figure-8 broadside to the axis of the array
CCardioid
DOmni-directional

46. - E9D05

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

SelectAnswer
AThe SWR is reduced
BThe frequency response is widened over the whole frequency band
CThe front-to-back ratio increases
DThe front-to-back ratio decreases

47. - E9E09

Which of the following is used to shunt-feed a grounded tower at its base?

SelectAnswer
ADouble-bazooka match
BAll these choices are correct
CHairpin match
DGamma match

48. - E9F07

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

SelectAnswer
ALower loss
BSmaller reflection coefficient
CHigher SWR
DLower velocity factor

49. - E9G01

Which of the following can be calculated using a Smith chart?

SelectAnswer
AImpedance along transmission lines
BRadiation resistance
CAntenna radiation pattern
DRadio propagation

50. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

SelectAnswer
AIts overall length must not exceed 1/4 wavelength
BIt should be configured as a four-sided loop
CIt should be one or more wavelengths long
DIt must be mounted more than 1 wavelength above ground

Figure E5-1

Figure E7-2

Figure E9-2