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

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1. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

SelectAnswer
AEnsure signals from your station are less than the controlled Maximum Permitted Exposure (MPE) limits
BEnsure signals from your station are less than the uncontrolled Maximum Permitted Emission (MPE) limits
CEnsure signals from your station are less than the controlled Maximum Permitted Emission (MPE) limits
DEnsure signals from your station are less than the uncontrolled Maximum Permitted Exposure (MPE) limits

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
BAny person holding an FCC issued amateur license or who is authorized for alien reciprocal operation
COnly a person named in an amateur station license grant
DOnly a person with an FCC Marine Radio 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
A15 kHz
B3 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
AOperators must not operate until approval is received
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 may not operate until a test signal has been transmitted in coordination with the local power company
DOperations may commence immediately, and may continue unless interference is reported by the UTC

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

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

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
BIssue the examinee the new or upgrade license
CThree VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
DPhotocopy all examination documents and forward them to the FCC for processing

7. - E1F09

Which of the following conditions apply when transmitting spread spectrum emissions?

SelectAnswer
AThe transmission must not be used to obscure the meaning of any communication
BAll these choices are correct
CThe transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions
DA station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions

8. - E2A12

What is the purpose of digital store-and-forward functions on an amateur radio satellite?

SelectAnswer
ATo store digital messages in the satellite for later download by other stations
BTo delay download of telemetry between satellites
CTo relay messages between satellites
DTo upload operational software for the transponder

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
BUsing converted satellite TV dishes
CUsing USB and demodulating the signal with a computer sound card
DTransmitting on the abandoned TV channel 2

10. - E2C07

What is the Cabrillo format?

SelectAnswer
AThe rules of order for meetings between contest sponsors
BA method of exchanging information during a contest QSO
CA standard for submission of electronic contest logs
DThe most common set of contest rules

11. - E2D08

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

SelectAnswer
ADisconnect
BAcknowledgement
CUnnumbered Information
DConnect

12. - E2E01

Which of the following types of modulation is common for data emissions below 30 MHz?

SelectAnswer
ASpread spectrum
BPulse modulation
CFSK
DDTMF tones modulating an FM signal

13. - E3A13

Which of these emission modes is best for auroral propagation?

SelectAnswer
AFM
BCW
CRTTY
DSSB

14. - E3B11

At what time of day can sporadic E propagation occur?

SelectAnswer
AOnly in hours of darkness
BOnly around sunset and sunrise
CAny time
DOnly around sunset

15. - E3C09

How does the intensity of an X3 flare compare to that of an X2 flare?

SelectAnswer
A50 percent greater
BTwice as great
C10 percent greater
DFour times as great

16. - E4A02

Which of the following parameters does a spectrum analyzer display on the vertical and horizontal axes?

SelectAnswer
ASWR and frequency
BRF amplitude and frequency
CSWR and time
DRF amplitude and time

17. - E4B08

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

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

18. - E4C04

What is the noise figure of a receiver?

SelectAnswer
AThe ratio of the noise bandwidth in hertz to the theoretical bandwidth of a resistive network
BThe ratio of thermal noise to atmospheric noise
CThe ratio in dB of the noise generated by the receiver to the theoretical minimum noise
DThe ratio of atmospheric noise to phase noise

19. - E4D09

What is the purpose of the preselector in a communications receiver?

SelectAnswer
ATo store often-used frequencies
BTo allow selection of the optimum RF amplifier device
CTo increase rejection of signals outside the desired band
DTo provide a range of AGC time constants

20. - E4E11

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

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

21. - E5A16

What is the resonant frequency of an RLC circuit if R is 33 ohms, L is 50 microhenries and C is 10 picofarads?

SelectAnswer
A23.5 MHz
B7.12 MHz
C7.12 kHz
D23.5 kHz

22. - E5B06

What is susceptance?

SelectAnswer
AThe ratio of magnetic field to electric field
BThe magnetic impedance of a circuit
CA measure of the efficiency of a transformer
DThe imaginary part of admittance

23. - E5C01

Which of the following represents capacitive reactance in rectangular notation?

SelectAnswer
AOmega
BDelta
C-jX
D+jX

24. - E5D09

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

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

25. - E6A07

Which of the following indicates that a silicon NPN junction transistor is biased on?

SelectAnswer
ABase-to-emitter resistance of approximately 0.6 to 0.7 ohms
BBase-to-emitter voltage of approximately 0.6 to 0.7 volts
CBase-to-emitter voltage of approximately 6 to 7 volts
DBase-to-emitter resistance of approximately 6 to 7 ohms

26. - E6B03

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

SelectAnswer
AForward bias
BInductive bias
CReverse bias
DZero bias

27. - E6C07

What best describes a pull-up or pull-down resistor?

SelectAnswer
AA resistor connected to an op-amp output that prevents signals from exceeding the power supply voltage
BA resistor that ensures that an oscillator frequency does not drift
CA resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit
DA resistor in a keying circuit used to reduce key clicks

28. - E6D05

What is one reason for using ferrite cores rather than powdered iron in an inductor?

SelectAnswer
AFerrite toroids generally have lower initial permeability
BFerrite toroids generally require fewer turns to produce a given inductance value
CFerrite toroids are easier to use with surface mount technology
DFerrite toroids generally have better temperature stability

29. - E6E01

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

SelectAnswer
AHigher electron mobility
BLower transconductance
CHigher noise figures
DLower junction voltage drop

30. - E6F09

What is the efficiency of a photovoltaic cell?

SelectAnswer
AThe relative fraction of light that is converted to current
BThe open-circuit voltage divided by the short-circuit current under full illumination
CThe output RF power divided by the input DC power
DCost per kilowatt-hour generated

31. - E7A08

What logical operation does an OR gate perform?

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

32. - E7B05

What can be done to prevent unwanted oscillations in an RF power amplifier?

SelectAnswer
ATune the stage for maximum SWR
BTune both the input and output for maximum power
CInstall parasitic suppressors and/or neutralize the stage
DUse a phase inverter in the output filter

33. - E7C11

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

SelectAnswer
ANoise factor
BPassband ripple
CShape factor
DPhase response

34. - E7D05

Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?

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

35. - E7E05

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

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

36. - E7F04

What is a common method of generating an SSB signal using digital signal processing?

SelectAnswer
ASignals are combined in quadrature phase relationship
BVarying quartz crystal characteristics emulated in digital form
CMixing products are converted to voltages and subtracted by adder circuits
DA frequency synthesizer removes the unwanted sidebands

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. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

SelectAnswer
AA diode-switching matrix synthesizer
BA direct digital synthesizer
CA phase-locked loop synthesizer
DA hybrid synthesizer

39. - E8A02

Which of the following is a type of analog-to-digital conversion?

SelectAnswer
AHarmonic regeneration
BLevel shifting
CSuccessive approximation
DPhase reversal

40. - E8B10

What is frequency division multiplexing?

SelectAnswer
ATwo or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
BThe transmitted signal jumps from band to band at a predetermined rate
CThe transmitted signal is divided into packets of information
DTwo or more information streams are merged into a baseband, which then modulates the transmitter

41. - E8C05

What is the approximate bandwidth of a 13-WPM International Morse Code transmission?

SelectAnswer
A104 Hz
B13 Hz
C52 Hz
D26 Hz

42. - E8D09

What is considered an acceptable maximum IMD level for an idling PSK signal?

SelectAnswer
A-30 dB
B+10 dB
C-20 dB
D+15 dB

43. - E9A10

Which of the following improves the efficiency of a ground-mounted quarter-wave vertical antenna?

SelectAnswer
AInstalling a radial system
BIsolating the coax shield from ground
CAll these choices are correct
DShortening the radiating element

44. - E9B03

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-side ratio?

SelectAnswer
A24 dB
B14 dB
C12 dB
D18 dB

45. - E9C07

What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?

SelectAnswer
A300 ohms
B72 ohms
C450 ohms
D50 ohms

46. - E9D05

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

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

47. - E9E11

What is the primary purpose of phasing lines when used with an antenna having multiple driven elements?

SelectAnswer
AIt prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
BIt ensures that each driven element operates in concert with the others to create the desired antenna pattern
CIt allows single-band antennas to operate on other bands
DIt creates a low-angle radiation pattern

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. - E9G11

How are the wavelength scales on a Smith chart calibrated?

SelectAnswer
AIn fractions of antenna electrical wavelength
BIn fractions of transmission line electrical wavelength
CIn fractions of transmission line electrical frequency
DIn fractions of antenna electrical frequency

50. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

SelectAnswer
ALow loss coax transmission line is essential for good performance
BAll these choices are correct
CAtmospheric noise is so high that gain over a dipole is not important
DThey must be erected at least 1/2 wavelength above the ground to attain good directivity

Figure E7-3

Figure E9-1