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

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1. - E0A05

What is one of the potential hazards of operating in the amateur radio microwave bands?

SelectAnswer
AMicrowaves often travel long distances by ionospheric reflection
BThe high gain antennas commonly used can result in high exposure levels
CMicrowaves are ionizing radiation
DThe extremely high frequency energy can damage the joints of antenna structures

2. - E1A08

If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

SelectAnswer
AThe control operators of all the stations in the system
BThe control operator of the originating station
CThe control operators of all the stations in the system not authenticating the source from which they accept communications
DThe control operator of the packet bulletin board station

3. - E1B07

To what type of regulations does PRB-1 apply?

SelectAnswer
AFAA tower height limits
BHomeowners associations
CState and local zoning
DUse of wireless devices in vehicles

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
CAll these choices are correct
DCEPT agreement

5. - E1D01

What is the definition of telemetry?

SelectAnswer
AOne-way transmission that initiates, modifies, or terminates the functions of a device at a distance
BOne-way transmission of measurements at a distance from the measuring instrument
CTwo-way transmissions of data
DTwo-way transmissions in excess of 1000 feet

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
BIssue the examinee the new or upgrade license
CAll these choices are correct
DPhotocopy all examination documents and forward them to the FCC for processing

7. - E1F01

On what frequencies are spread spectrum transmissions permitted?

SelectAnswer
AOnly on amateur frequencies above 144 MHz
BOnly on amateur frequencies above 50 MHz
COnly on amateur frequencies above 420 MHz
DOnly on amateur frequencies above 222 MHz

8. - E2A04

What is meant by the term mode? as applied to an amateur radio satellite?

SelectAnswer
AWhether the satellite is in a low earth or geostationary orbit
BWhether the satellite is in a polar or equatorial orbit
CThe satellite's orientation with respect to the Earth
DThe satellite's uplink and downlink frequency bands

9. - E2B08

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

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

10. - E2C01

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control and the remote transmitter is located in the U.S.?

SelectAnswer
ANo additional indicator is required
B/ followed by the USPS two-letter abbreviation for the state in which the remote station is located
C/ followed by the ARRL Section of the remote station
D/R# where # is the district of the remote station

11. - E2D02

Which of the following is a good technique for making meteor scatter contacts?

SelectAnswer
A15-second timed transmission sequences with stations alternating based on location
BUse of special digital modes
CShort transmissions with rapidly repeated call signs and signal reports
DAll these choices are correct

12. - E2E03

How is the timing of FT4 contacts organized?

SelectAnswer
AStations take turns on alternate days
BAlternating transmissions at 7.5 second intervals
CBy exchanging ACK/NAK packets
DIt depends on the lunar phase

13. - E3A12

What is the cause of auroral activity?

SelectAnswer
AThe interaction in the E layer of charged particles from the Sun with the Earth's magnetic field
BMeteor showers concentrated in the extreme northern and southern latitudes
CThe interaction in the F2 layer between the solar wind and the Van Allen belt
DAn extreme low-pressure area in the polar regions

14. - E3B12

What is the primary characteristic of chordal hop propagation?

SelectAnswer
APropagation across the geomagnetic equator
BPropagation away from the great circle bearing between stations
CSuccessive ionospheric refractions without an intermediate reflection from the ground
DSignals reflected back toward the transmitting station

15. - E3C10

What does the 304A solar parameter measure?

SelectAnswer
AUV emissions at 304 angstroms, correlated to the solar flux index
BThe ratio of x-ray flux to radio flux, correlated to sunspot number
CThe solar emission at 304 GHz, correlated to x-ray flare levels
DThe solar wind velocity at 304 degrees from the solar equator, correlated to solar activity

16. - E4A01

Which of the following limits the highest frequency signal that can be accurately displayed on a digital oscilloscope?

SelectAnswer
AAll these choices are correct
BQ of the circuit
CAmount of memory
DSampling rate of the analog-to-digital converter

17. - E4B04

Which S parameter represents input port return loss or reflection coefficient (equivalent to VSWR)?

SelectAnswer
AS11
BS21
CS22
DS12

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 of atmospheric noise to phase noise
DThe ratio in dB of the noise generated by the receiver to the theoretical minimum noise

19. - E4D01

What is meant by the blocking dynamic range of a receiver?

SelectAnswer
AThe minimum difference in dB between the levels of two FM signals that will cause one signal to block the other
BThe difference in dB between the noise floor and the third-order intercept point
CThe difference in dB between the noise floor and the level of an incoming signal that will cause 1 dB of gain compression
DThe minimum difference in dB between two signals which produce third-order intermodulation products greater than the noise floor

20. - E4E04

How can conducted and radiated noise caused by an automobile alternator be suppressed?

SelectAnswer
ABy connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads
BBy installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead
CBy installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead
DBy installing a noise suppression resistor and a blocking capacitor in both leads

21. - E5A10

How is the Q of an RLC series resonant circuit calculated?

SelectAnswer
AReactance of the inductance multiplied by the reactance of the capacitance
BReactance of either the inductance or capacitance divided by the resistance
CResistance divided by the reactance of either the inductance or capacitance
DReactance of either the inductance or capacitance multiplied by the resistance

22. - E5B01

What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the applied voltage or to discharge to 36.8% of its initial voltage?

SelectAnswer
AAn exponential rate of one
BA time factor of one
COne exponential period
DOne time constant

23. - E5C08

What coordinate system is often used to display the phase angle of a circuit containing resistance, inductive and/or capacitive reactance?

SelectAnswer
AElliptical coordinates
BMaidenhead grid
CPolar coordinates
DFaraday grid

24. - E5D05

What is the power factor of an RL circuit having a 30-degree phase angle between the voltage and the current?

SelectAnswer
A0.577
B0.5
C1.73
D0.866

25. - E6A01

In what application is gallium arsenide used as a semiconductor material?

SelectAnswer
AIn very low-frequency RF circuits
BIn high-power audio circuits
CIn high-current rectifier circuits
DIn microwave circuits

26. - E6B01

What is the most useful characteristic of a Zener diode?

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

27. - E6C11

In Figure E6-3, what is the schematic symbol for the NOT operation (inverter)?

SelectAnswer
A4
B6
C5
D2

28. - E6D11

Which type of core material decreases inductance when inserted into a coil?

SelectAnswer
AFerrite
BBrass
CPowdered iron
DCeramic

29. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

SelectAnswer
AControlled gain, low noise figure, and constant input and output impedance over the specified frequency range
BPlate current that is controlled by a control grid
CNearly infinite gain, very high input impedance, and very low output impedance
DThe ability to retrieve information from a single signal even in the presence of other strong signals

30. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

SelectAnswer
ASilicon
BCopper oxide
CCadmium Sulfide
DSelenium

31. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

SelectAnswer
AA multiplexer
BAn OR gate
CAn XOR gate
DA flip-flop

32. - E7B10

In Figure E7-1, what is the purpose of R1 and R2?

SelectAnswer
AFeedback
BLoad resistors
CVoltage divider bias
DSelf bias

33. - E7C05

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

SelectAnswer
AA passive op-amp filter
BAn active LC filter
CA Butterworth filter
DA Chebyshev filter

34. - E7D13

What is the equation for calculating power dissipated by a series linear voltage regulator?

SelectAnswer
AOutput voltage multiplied by output current
BInput voltage divided by output current
CInput voltage multiplied by input current
DVoltage difference from input to output multiplied by output current

35. - E7E11

Which type of detector circuit is used for demodulating SSB signals?

SelectAnswer
ADiscriminator
BProduct detector
CPhase comparator
DPhase detector

36. - E7F04

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

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

37. - E7G12

What is an operational amplifier?

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

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

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 sine wave
BA square wave
CA sawtooth wave
DA cosine wave

40. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

SelectAnswer
A0.214
B2.14
C47
D0.47

41. - E8C12

What factors affect the bandwidth of a transmitted CW signal?

SelectAnswer
AModulation index and output power
BKeying speed and shape factor (rise and fall time)
CAll these choices are correct
DIF bandwidth and Q

42. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

SelectAnswer
ALimits data speed
BThe generation of RF harmonics
CThe generation of key clicks
DMore difficult to copy

43. - E9A09

What is antenna efficiency?

SelectAnswer
AEffective radiated power divided by transmitter output
BRadiation resistance divided by transmission resistance
CTotal resistance divided by radiation resistance
DRadiation resistance divided by total resistance

44. - E9B09

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

SelectAnswer
ACalculus differentiation with respect to physical properties
BMutual impedance analysis
CGraphical analysis
DMethod of Moments

45. - E9C08

What is a folded dipole antenna?

SelectAnswer
AA type of ground-plane antenna
BA dipole configured to provide forward gain
CA dipole one-quarter wavelength long
DA half-wave dipole with an additional parallel wire connecting its two ends

46. - E9D10

What happens to feed-point impedance at the base of a fixed length HF mobile antenna when operated below its resonant frequency?

SelectAnswer
AThe radiation resistance decreases and the capacitive reactance increases
BThe radiation resistance increases and the capacitive reactance increases
CThe radiation resistance increases and the capacitive reactance decreases
DThe radiation resistance decreases and the capacitive reactance decreases

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
A62 ohms
B450 ohms
C50 ohms
D75 ohms

48. - E9F02

Which of the following has the biggest effect on the velocity factor of a transmission line?

SelectAnswer
AThe line length
BDielectric materials used in the line
CThe center conductor resistivity
DThe termination impedance

49. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

SelectAnswer
AVoltage and impedance
BReactance and voltage
CResistance and reactance
DResistance and voltage

50. - E9H06

What is the triangulation method of direction finding?

SelectAnswer
AA fixed receiving station plots three headings to the signal source
BA fixed receiving station uses three different antennas to plot the location of the signal source
CAntenna headings from several different receiving locations are used to locate the signal source
DThe geometric angles of sky waves from the source are used to determine its position

Figure E6-3

Figure E7-1