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

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1. - E0A10

What toxic material may be present in some electronic components such as high voltage capacitors and transformers?

SelectAnswer
APolychlorinated biphenyls
BPolytetrafluoroethylene
CPolymorphic silicon
DPolyethylene

2. - E1A13

Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?

SelectAnswer
AAny person named in an amateur station license grant or a person holding an unrestricted Radiotelephone Operator Permit
BOnly a person named in an amateur station license grant
CAny person holding an FCC issued amateur license or who is authorized for alien reciprocal operation
DOnly a person with an FCC Marine Radio license grant

3. - E1B10

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

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

4. - E1C01

What is the maximum bandwidth for a data emission on 60 meters?

SelectAnswer
A2.8 kHz
B1.5 kHz
C60 Hz
D170 Hz

5. - E1D03

What is a space telecommand station?

SelectAnswer
AAn amateur station that transmits communications to initiate, modify or terminate functions of a space station
BAn amateur station located in a satellite or a balloon more than 50 kilometers above the surface of the Earth
CAn amateur station located on the surface of the Earth for communication with other Earth stations by means of Earth satellites
DAn amateur station that receives telemetry from a satellite or balloon more than 50 kilometers above the surface of the Earth

6. - E1E11

What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

SelectAnswer
AAll these choices are correct
BThree VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
CPhotocopy all examination documents and forward them to the FCC for processing
DIssue the examinee the new or upgrade license

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
A420 MHz - 430 MHz
B53 MHz - 54 MHz
C440 MHz - 450 MHz
D222 MHz - 223 MHz

8. - E2A03

How is the signal inverted by an inverting linear transponder?

SelectAnswer
AThe signal is detected and remodulated on the reverse sideband
BThe signal is passed through a non-linear filter
CThe signal is passed through a mixer and the difference rather than the sum is transmitted
DThe signal is reduced to I and Q components and the Q component is filtered out

9. - E2B10

What aspect of an analog slow-scan television signal encodes the brightness of the picture?

SelectAnswer
ATone amplitude
BTone frequency
CSync amplitude
DSync frequency

10. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

SelectAnswer
AContacts between a U.S. station and a non-U.S. station
BRepeater contacts between U.S. club members
CContacts using tactical call signs
DSpecial event contacts between stations in the U.S.

11. - E2D11

Which of the following data are used by the APRS network to communicate station location?

SelectAnswer
APolar coordinates
BLatitude and longitude
CTime and frequency
DRadio direction finding spectrum analysis

12. - E2E12

How do ALE stations establish contact?

SelectAnswer
AALE radios activate when they hear their signal echoed by back scatter
BALE radios send a constant tone code to establish a frequency for future use
CALE radios monitor an internet site for the frequency they are being paged on
DALE constantly scans a list of frequencies, activating the radio when the designated call sign is received

13. - E3A14

What is meant by circularly polarized electromagnetic waves?

SelectAnswer
AWaves produced by a loop antenna
BWaves that circle the Earth
CWaves with a rotating electric field
DWaves with an electric field bent into a circular shape

14. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

SelectAnswer
A7500 miles
B1000 miles
C5000 miles
D2500 miles

15. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

SelectAnswer
ANVIS
BTransequatorial
CSporadic E
DPolar

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

17. - E4B05

What three test loads are used to calibrate an RF vector network analyzer?

SelectAnswer
AShort circuit, open circuit, and 50 ohms
BShort circuit, open circuit, and resonant circuit
C50 ohms, 75 ohms, and 90 ohms
D50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable

18. - E4C01

What is an effect of excessive phase noise in a receiver's local oscillator?

SelectAnswer
AIt can affect the receiver's frequency calibration
BIt limits the receiver's ability to receive strong signals
CIt can combine with strong signals on nearby frequencies to generate interference
DIt decreases receiver third-order intercept point

19. - E4D02

Which of the following describes problems caused by poor dynamic range in a receiver?

SelectAnswer
ACross-modulation of the desired signal and insufficient audio power to operate the speaker
BOscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
CSpurious signals caused by cross-modulation and desensitization from strong adjacent signals
DOscillator instability and severe audio distortion of all but the strongest received signals

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
BRemoval of the CW signal as well as the interfering carrier
CRinging in the DSP filter will completely remove the spaces between the CW characters
DReceived CW signals will appear to be modulated at the DSP clock frequency

21. - E5A15

Which of the following increases Q for inductors and capacitors?

SelectAnswer
AHigher self-resonant frequency
BLower self-resonant frequency
CLower reactance
DLower losses

22. - E5B05

What happens to the magnitude of a pure reactance when it is converted to a susceptance?

SelectAnswer
AThe sign is reversed
BIt is unchanged
CIt becomes the reciprocal
DIt is shifted by 90 degrees

23. - E5C02

How are impedances described in polar coordinates?

SelectAnswer
ABy X and R values
BBy phase angle and magnitude
CBy real and imaginary parts
DBy Y and G values

24. - E5D12

How many watts are consumed in a circuit having a power factor of 0.2 if the input is 100 VAC at 4 amperes?

SelectAnswer
A400 watts
B50 watts
C80 watts
D2000 watts

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. - E6B03

What type of bias is required for an LED to emit light?

SelectAnswer
AZero bias
BReverse bias
CForward bias
DInductive bias

27. - E6C09

What is a Programmable Logic Device (PLD)?

SelectAnswer
AA logic circuit that can be modified during use
BProgrammable equipment used for testing digital logic integrated circuits
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. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

SelectAnswer
AButterworth filters
BFerrite beads
CSteel-core toroids
DElectrolytic capacitors

29. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

SelectAnswer
AA total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
BLow leakage doubly insulated package
CTwo chips in each package (Dual In Package)
DPackage mounts in a direct inverted position

30. - E6F02

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

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

31. - E7A07

What logical operation does a NAND gate perform?

SelectAnswer
AIt produces logic 0 at its output only when all inputs are logic 0
BIt produces logic 1 at its output only when all inputs are logic 1
CIt produces logic 0 at its output only when all inputs are logic 1
DIt produces logic 0 at its output if some but not all inputs are logic 1

32. - E7B06

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

SelectAnswer
AClass AB
BClass C
CPush-pull
DPush-push

33. - E7C06

What are the distinguishing features of an elliptical filter?

SelectAnswer
AGradual passband rolloff with extreme stop band ripple
BExtremely flat response over its pass band with gradually rounded stop band corners
CGradual passband rolloff with minimal stop band ripple
DExtremely sharp cutoff with one or more notches in the stop band

34. - E7D07

What is the purpose of C2 in the circuit shown in Figure E7-2?

SelectAnswer
ATo self-resonate at the hum frequency
BTo provide fixed DC bias for Q1
CIt is a brute force filter for the output
DIt bypasses rectifier output ripple around D1

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 lowest frequency band that the transmitter or receiver covers
CThe unmodulated bandwidth of the transmitted signal
DThe basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency

36. - E7F02

What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

SelectAnswer
AA crystal-lattice filter
BAn adaptive filter
CA phase-inverting filter
DA Hilbert-transform filter

37. - E7G10

What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 1800 ohms and RF is 68 kilohms?

SelectAnswer
A76
B1
C0.03
D38

38. - E7H14

What is a phase-locked loop circuit?

SelectAnswer
AAn electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
BAn electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
CAn electronic circuit also known as a monostable multivibrator
DAn electronic circuit consisting of a precision push-pull amplifier with a differential input

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
BVector analysis
CNumerical analysis
DDifferential analysis

40. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

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

41. - E8C01

How is Forward Error Correction implemented?

SelectAnswer
ABy the receiving station repeating each block of three data characters
BBy transmitting a special algorithm to the receiving station along with the data characters
CBy transmitting extra data that may be used to detect and correct transmission errors
DBy varying the frequency shift of the transmitted signal according to a predefined algorithm

42. - E8D02

What spread spectrum communications technique uses a high-speed binary bit stream to shift the phase of an RF carrier?

SelectAnswer
APhase compandored spread spectrum
BDirect sequence
CBinary phase-shift keying
DFrequency hopping

43. - E9A12

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 6 dB gain over an isotropic antenna?

SelectAnswer
A3.85 dB
B6.0 dB
C8.15 dB
D2.79 dB

44. - E9B09

What type of computer program technique is commonly used for modeling antennas?

SelectAnswer
AMutual impedance analysis
BMethod of Moments
CCalculus differentiation with respect to physical properties
DGraphical analysis

45. - E9C14

How does the performance of a horizontally polarized antenna mounted on the side of a hill compare with the same antenna mounted on flat ground?

SelectAnswer
AThe main lobe takeoff angle decreases in the downhill direction
BThe main lobe takeoff angle increases in the downhill direction
CThe horizontal beamwidth increases in the uphill direction
DThe horizontal beamwidth decreases in the downhill direction

46. - E9D04

Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?

SelectAnswer
ATo minimize losses
BTo minimize the Q
CTo swamp out harmonics
DTo lower the radiation angle

47. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

SelectAnswer
AThe delta match
BThe gamma match
CThe epsilon match
DThe stub match

48. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically 1/4 wavelength long at 14.1 MHz?

SelectAnswer
A4.3 meters
B10.6 meters
C5.3 meters
D3.5 meters

49. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

SelectAnswer
AAntenna-length circles
BCoaxial-length circles
CStanding wave ratio circles
DRadiation-pattern circles

50. - E9H04

What is an advantage of placing a grounded electrostatic shield around a small loop direction-finding antenna?

SelectAnswer
AIt adds capacitive loading, increasing the bandwidth of the antenna
BIt increases signal strength by providing a better match to the feed line
CIt eliminates tracking errors caused by strong out-of-band signals
DIt eliminates unbalanced capacitive coupling to the surroundings, improving the nulls

Figure E7-2

Figure E7-3