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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
A30 to 300 MHz
B3 to 30 MHz
C300 kHz to 3 MHz
D300 to 3000 MHz

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 with an FCC Marine Radio license grant
CAny person holding an FCC issued amateur license or who is authorized for alien reciprocal operation
DOnly a person named in an amateur station license grant

3. - E1B02

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

SelectAnswer
A3 kHz
B15 kHz
C10 kHz
D20 kHz

4. - E1C14

How long must an operator wait after filing a notification with the Utilities Technology Council (UTC) before operating on the 2200 meter or 630 meter band?

SelectAnswer
AOperations may commence immediately, and may continue unless interference is reported by the UTC
BOperators may operate after 30 days, providing they have not been told that their station is within 1 km of PLC systems using those frequencies
COperators must not operate until approval is received
DOperators may not operate until a test signal has been transmitted in coordination with the local power company

5. - E1D09

Which UHF amateur bands have frequencies authorized for space stations?

SelectAnswer
A70 cm and 33 cm
B70 cm only
C70 cm and 13 cm
D33 cm and 13 cm

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
AThree VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
BAll these choices are correct
CIssue the examinee the new or upgrade license
DPhotocopy all examination documents and forward them to the FCC for processing

7. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

SelectAnswer
ATo allow regular operation on Land Mobile channels
BTo provide for experimental amateur communications
CTo provide additional spectrum for personal use
DTo provide temporary operation while awaiting normal licensing

8. - E2A01

What is the direction of an ascending pass for an amateur satellite?

SelectAnswer
AFrom north to south
BFrom west to east
CFrom south to north
DFrom east to west

9. - E2B06

What is vestigial sideband modulation?

SelectAnswer
AAmplitude modulation in which one complete sideband and a portion of the other are transmitted
BA type of modulation in which one sideband is inverted
CNarrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier
DSpread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation

10. - E2C02

Which of the following best describes the term self-spotting? in connection with HF contest operating?

SelectAnswer
AThe acceptable practice of manually posting the call signs of stations on a spotting network
BAn automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
CA manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
DThe often-prohibited practice of posting one's own call sign and frequency on a spotting network

11. - E2D08

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

SelectAnswer
AConnect
BUnnumbered Information
CDisconnect
DAcknowledgement

12. - E2E09

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

SelectAnswer
APACTOR
BMT63
CRTTY
DPSK31

13. - E3A14

What is meant by circularly polarized electromagnetic waves?

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

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 solstices, especially the summer solstice
DAround the equinoxes, especially the fall equinox

15. - E3C13

What type of polarization is best for ground-wave propagation?

SelectAnswer
AHorizontal
BVertical
CCircular
DElliptical

16. - E4A10

Which of the following displays multiple digital signal states simultaneously?

SelectAnswer
ABit error rate tester
BLogic analyzer
CNetwork analyzer
DModulation monitor

17. - E4B10

Which of the following methods measures intermodulation distortion in an SSB transmitter?

SelectAnswer
AModulate the transmitter using two RF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer
BModulate the transmitter using two AF signals having harmonically related frequencies and observe the RF output with a peak reading wattmeter
CModulate the transmitter using two RF signals having harmonically related frequencies and observe the RF output with a logic analyzer
DModulate the transmitter using two AF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer

18. - E4C09

Which of the following choices is a good reason for selecting a high frequency for the design of the IF in a superheterodyne HF or VHF communications receiver?

SelectAnswer
AImproved receiver noise figure
BEasier for front-end circuitry to eliminate image responses
CFewer components in the receiver
DReduced drift

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. - E4E11

What could cause local AM broadcast band signals to combine to generate spurious signals in the MF or HF bands?

SelectAnswer
AYour station receiver IF amplifier stage is defective
BOne or more of the broadcast stations is transmitting an over-modulated signal
CYou are receiving skywave signals from a distant station
DNearby corroded metal joints are mixing and re-radiating the broadcast signals

21. - E5A13

What is an effect of increasing Q in a series resonant circuit?

SelectAnswer
APhase shift can become uncontrolled
BInternal voltages increase
CParasitic effects are minimized
DFewer components are needed for the same performance

22. - E5B02

What letter is commonly used to represent susceptance?

SelectAnswer
AG
BB
CY
DX

23. - E5C07

Where is the impedance of a pure resistance plotted on rectangular coordinates?

SelectAnswer
AOn the horizontal axis
BOn a horizontal line, offset vertically above the horizontal axis
COn a line through the origin, slanted at 45 degrees
DOn the vertical axis

24. - E5D07

How many watts are consumed in a circuit having a power factor of 0.71 if the apparent power is 500VA?

SelectAnswer
A1.42 mW
B355 W
C704 W
D252 W

25. - E6A10

In Figure E6-1, what is the schematic symbol for an N-channel dual-gate MOSFET?

SelectAnswer
A5
B4
C6
D2

26. - E6B01

What is the most useful characteristic of a Zener diode?

SelectAnswer
AA negative resistance region
BA constant current drop under conditions of varying voltage
CAn internal capacitance that varies with the applied voltage
DA constant voltage drop under conditions of varying current

27. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

SelectAnswer
AImmune to damage from static discharge
BLower distortion
CLower power consumption
DDifferential output capability

28. - E6D12

What is inductor saturation?

SelectAnswer
AThe inductor's voltage rating is exceeded causing a flashover
BThe ability of the inductor's core to store magnetic energy has been exceeded
CAdjacent inductors become over-coupled
DThe inductor windings are over-coupled

29. - E6E01

Why is gallium arsenide (GaAs) useful for semiconductor devices operating at UHF and higher frequencies?

SelectAnswer
ALower transconductance
BHigher noise figures
CLower junction voltage drop
DHigher electron mobility

30. - E6F08

Why are optoisolators often used in conjunction with solid-state circuits when switching 120 VAC?

SelectAnswer
AOptoisolators provide a very high degree of electrical isolation between a control circuit and the circuit being switched
BOptoisolators provide impedance matching between the control circuit and power circuit
COptoisolators provide a low impedance link between a control circuit and a power circuit
DOptoisolators eliminate the effects of reflected light in the control circuit

31. - E7A08

What logical operation does an OR gate perform?

SelectAnswer
AIt only produces logic 0 at its output when all inputs are logic 1
BIt produces logic 0 at its output if all inputs are logic 1
CIt produces logic 1 at its output if any or all inputs are logic 1
DIt produces logic 1 at its output if all inputs are logic 0

32. - E7B01

For what portion of the signal cycle does each active element in a push-pull Class AB amplifier conduct?

SelectAnswer
AThe entire cycle
BLess than 180 degrees
CMore than 180 degrees but less than 360 degrees
DExactly 180 degrees

33. - E7C03

What advantage does a series-L Pi-L-network have over a series-L Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

SelectAnswer
AGreater harmonic suppression
BDoes not require a capacitor
CHigher efficiency
DGreater transformation range

34. - E7D07

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

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

35. - E7E04

What is one way a single-sideband phone signal can be generated?

SelectAnswer
ABy driving a product detector with a DSB signal
BBy using a loop modulator followed by a mixer
CBy using a reactance modulator followed by a mixer
DBy using a balanced modulator followed by a filter

36. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

SelectAnswer
AAn elliptical filter
BAn adaptive filter
CA notch filter
DA Hilbert-transform filter

37. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 3300 ohms and RF is 47 kilohms?

SelectAnswer
A14
B7
C28
D0.07

38. - E7H03

How is positive feedback supplied in a Hartley oscillator?

SelectAnswer
AThrough a tapped coil
BThrough a neutralizing capacitor
CThrough a capacitive divider
DThrough link coupling

39. - E8A04

What is "dither" with respect to analog-to-digital converters?

SelectAnswer
AAn abnormal condition where the converter cannot settle on a value to represent the signal
BAn error caused by irregular quantization step size
CA method of decimation by randomly skipping samples
DA small amount of noise added to the input signal to allow more precise representation of a signal over time

40. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

SelectAnswer
A3000
B0.3
C3
D1000

41. - E8C11

What is the relationship between symbol rate and baud?

SelectAnswer
AThey are the same
BBaud is only used for RTTY
CSymbol rate is only used for packet-based modes
DBaud is twice the symbol rate

42. - E8D08

What parameter evaluates distortion of an AFSK signal caused by excessive input audio levels?

SelectAnswer
ASignal-to-noise ratio
BBaud rate
CRepeat Request Rate (RRR)
DIntermodulation Distortion (IMD)

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
A2.79 dB
B3.85 dB
C8.15 dB
D6.0 dB

44. - E9B05

What type of antenna pattern is shown in Figure E9-2?

SelectAnswer
AElevation
BRadiation resistance
CPolarization
DAzimuth

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

46. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

SelectAnswer
ALower Q
BImproved radiation efficiency
CHigher losses
DGreater structural strength

47. - E9E01

What system matches a higher-impedance transmission line to a lower-impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

SelectAnswer
AThe gamma matching system
BThe omega matching system
CThe delta matching system
DThe stub matching system

48. - E9F11

What impedance does a 1/8-wavelength transmission line present to a generator when the line is open at the far end?

SelectAnswer
AAn inductive reactance
BInfinite
CA capacitive reactance
DThe same as the characteristic impedance of the line

49. - E9G10

What do the arcs on a Smith chart represent?

SelectAnswer
AFrequency
BPoints with constant resistance
CSWR
DPoints with constant reactance

50. - E9H10

How can the output voltage of a multiple-turn receiving loop antenna be increased?

SelectAnswer
ABy utilizing high impedance wire for the coupling loop
BBy increasing the number of turns and/or the area
CBy winding adjacent turns in opposing directions
DBy reducing the permeability of the loop shield

Figure E6-1

Figure E7-2

Figure E7-3

Figure E9-2