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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
APolymorphic silicon
BPolychlorinated biphenyls
CPolyethylene
DPolytetrafluoroethylene

2. - E1A11

Which of the following describes authorization or licensing required when operating an amateur station aboard a U.S.-registered vessel in international waters?

SelectAnswer
AAny amateur license with an FCC Marine or Aircraft endorsement
BOnly General Class or higher amateur licenses
CAny FCC-issued amateur license
DAn unrestricted Radiotelephone Operator Permit

3. - E1B01

Which of the following constitutes a spurious emission?

SelectAnswer
AAny transmitted signal that unintentionally interferes with another licensed radio station
BAn amateur station transmission made without the proper call sign identification
CAn emission outside the signal's necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
DA signal transmitted to prevent its detection by any station other than the intended recipient

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
AIARP agreement
BITU reciprocal license
CCEPT agreement
DAll these choices are correct

5. - E1D09

Which UHF amateur bands have frequencies authorized for space stations?

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

6. - E1E01

For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

SelectAnswer
APreparing, processing, administering, and coordinating an examination for an amateur radio operator license
BProviding amateur operator license examination preparation training materials
CNo expenses are authorized for reimbursement
DTeaching an amateur operator license examination preparation course

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
A53 MHz - 54 MHz
B440 MHz - 450 MHz
C222 MHz - 223 MHz
D420 MHz - 430 MHz

8. - E2A08

Why should effective radiated power to a satellite that uses a linear transponder be limited?

SelectAnswer
ATo avoid reducing the downlink power to all other users
BTo prevent creating errors in the satellite telemetry
CTo avoid interfering with terrestrial QSOs
DTo prevent the satellite from emitting out-of-band signals

9. - E2B02

How many horizontal lines make up a fast-scan (NTSC) television frame?

SelectAnswer
A60
B1080
C525
D30

10. - E2C05

What is the function of a DX QSL Manager?

SelectAnswer
ATo allocate frequencies for DXpeditions
BTo run a net to allow many stations to contact a rare DX station
CTo relay calls to and from a DX station
DTo handle the receiving and sending of confirmation cards for a DX station

11. - E2D06

Which of the following describes a method of establishing EME contacts?

SelectAnswer
AStoring and forwarding digital messages
BJudging optimum transmission times by monitoring beacons reflected from the moon
CHigh-speed CW identification to avoid fading
DTime synchronous transmissions alternately from each station

12. - E2E08

Which of the following HF digital modes can be used to transfer binary files?

SelectAnswer
AHellschreiber
BAMTOR
CRTTY
DPACTOR

13. - E3A13

Which of these emission modes is best for auroral propagation?

SelectAnswer
AFM
BRTTY
CSSB
DCW

14. - E3B05

Which amateur bands typically support long-path propagation?

SelectAnswer
A160 meters to 10 meters
BOnly 30 meters to 10 meters
C6 meters to 2 meters
DOnly 160 meters to 40 meters

15. - E3C11

What does VOACAP software model?

SelectAnswer
AAC voltage and impedance
BHF propagation
CAC current and impedance
DVHF radio propagation

16. - E4A11

How should an antenna analyzer be connected when measuring antenna resonance and feed point impedance?

SelectAnswer
ALoosely couple the antenna and a dummy load to the analyzer
BConnect the analyzer via a high-impedance transformer to the antenna
CLoosely couple the analyzer near the antenna base
DConnect the antenna feed line directly to the analyzer's connector

17. - E4B03

Which S parameter is equivalent to forward gain?

SelectAnswer
AS22
BS21
CS11
DS12

18. - E4C15

What is reciprocal mixing?

SelectAnswer
AIn-phase signals cancelling in a mixer resulting in loss of receiver sensitivity
BTwo out-of-band signals mixing to generate an in-band spurious signal
CLocal oscillator phase noise mixing with adjacent strong signals to create interference to desired signals
DTwo digital signals combining from alternate time slots

19. - E4D10

What does a third-order intercept level of 40 dBm mean with respect to receiver performance?

SelectAnswer
AA pair of 40 dBm input signals will theoretically generate a third-order intermodulation product that has the same output amplitude as either of the input signals
BA pair of 1 mW input signals will produce a third-order intermodulation product that is 40 dB stronger than the input signal
CThe receiver can tolerate signals up to 40 dB above the noise floor without producing third-order intermodulation products
DSignals less than 40 dBm will not generate audible third-order intermodulation products

20. - E4E08

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

SelectAnswer
AReturn current
BDifferential-mode current
CCommon-mode current
DReactive current only

21. - E5A08

What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?

SelectAnswer
AThe voltage leads the current by 90 degrees
BThe current leads the voltage by 90 degrees
CThe voltage and current are in phase
DThe voltage and current are 180 degrees out of phase

22. - E5B12

What is admittance?

SelectAnswer
AThe turns ratio of a transformer
BThe inverse of impedance
CThe term for the gain of a field effect transistor
DThe inverse of Q factor

23. - E5C09

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

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

24. - E5D02

Why is it important to keep lead lengths short for components used in circuits for VHF and above?

SelectAnswer
ATo increase the thermal time constant
BAll these choices are correct
CTo maintain component lifetime
DTo avoid unwanted inductive reactance

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 resistance of approximately 6 to 7 ohms
DBase-to-emitter voltage of approximately 6 to 7 volts

26. - E6B08

Which of the following is a Schottky barrier diode?

SelectAnswer
APIN junction
BThermionic emission diode
CElectrolytic rectifier
DMetal-semiconductor junction

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 in a keying circuit used to reduce key clicks
DA resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit

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
AElectrolytic capacitors
BSteel-core toroids
CFerrite beads
DButterworth filters

29. - E6E04

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

SelectAnswer
A10 ohms
B300 ohms
C450 ohms
D50 ohms

30. - E6F09

What is the efficiency of a photovoltaic cell?

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

31. - E7A04

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

SelectAnswer
A8
B1
C4
D2

32. - E7B16

What is the effect of intermodulation products in a linear power amplifier?

SelectAnswer
AAll these choices are correct
BLow efficiency
CTransmission of spurious signals
DCreation of parasitic oscillations

33. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

SelectAnswer
AA Butterworth filter
BA passive op-amp filter
CA Chebyshev filter
DAn active LC filter

34. - E7D12

What is the dropout voltage of an analog voltage regulator?

SelectAnswer
AMinimum input-to-output voltage required to maintain regulation
BMaximum that the output voltage may decrease at rated load
CMinimum input voltage for rated power dissipation
DMaximum output voltage drops when the input voltage is varied over its specified range

35. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

SelectAnswer
AA beat frequency is generated
BMixer blanking occurs
CSpurious mixer products are generated
DAutomatic limiting occurs

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 four times the rate of the highest frequency component of the signal
CAt least twice the rate of the highest frequency component of the signal
DAt the same rate as the highest frequency component of the signal

37. - E7G09

What will be the output voltage of the circuit shown in Figure E7-3 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

SelectAnswer
A-2.3 volts
B0.23 volts
C-0.23 volts
D2.3 volts

38. - E7H05

How is positive feedback supplied in a Pierce oscillator?

SelectAnswer
AThrough a tapped coil
BThrough a quartz crystal
CThrough link coupling
DThrough a neutralizing capacitor

39. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all its harmonics?

SelectAnswer
AA sawtooth wave
BA square wave
CA cosine wave
DA sine wave

40. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

SelectAnswer
A1.67
B0.167
C60
D0.6

41. - E8C09

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

SelectAnswer
AGray code
BExcess 3 code
CBinary Coded Decimal Code
DExtended Binary Coded Decimal Interchange Code

42. - E8D01

Why are received spread spectrum signals resistant to interference?

SelectAnswer
AThe receiver is always equipped with a digital blanker
BSignals not using the spread spectrum algorithm are suppressed in the receiver
CThe high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
DIf interference is detected by the receiver it will signal the transmitter to change frequencies

43. - E9A09

What is antenna efficiency?

SelectAnswer
ARadiation resistance divided by total resistance
BTotal resistance divided by radiation resistance
CRadiation resistance divided by transmission resistance
DEffective radiated power divided by transmitter output

44. - E9B05

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

SelectAnswer
AAzimuth
BElevation
CRadiation resistance
DPolarization

45. - E9C03

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed in phase?

SelectAnswer
AA Figure-8 end-fire along the axis of the array
BA Figure-8 broadside to the axis of the array
COmni-directional
DCardioid

46. - E9D11

Which of the following conductors would be best for minimizing losses in a station's RF ground system?

SelectAnswer
ASolid wire
BWide flat copper strap
CResistive wire, such as spark plug wire
DStranded wire

47. - E9E06

Which of these feed line impedances would be suitable for constructing a quarter-wave Q-section for matching a 100-ohm loop to 50-ohm feed line?

SelectAnswer
A50 ohms
B75 ohms
C62 ohms
D450 ohms

48. - E9F08

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

SelectAnswer
AFoam dielectric has lower loss per unit of length
BFoam dielectric has higher velocity factor
CAll these choices are correct
DFoam dielectric has lower safe operating voltage limits

49. - E9G10

What do the arcs on a Smith chart represent?

SelectAnswer
APoints with constant resistance
BFrequency
CPoints with constant reactance
DSWR

50. - E9H06

What is the triangulation method of direction finding?

SelectAnswer
AThe geometric angles of sky waves from the source are used to determine its position
BAntenna headings from several different receiving locations are used to locate the signal source
CA fixed receiving station uses three different antennas to plot the location of the signal source
DA fixed receiving station plots three headings to the signal source

Figure E7-3

Figure E9-2