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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
A300 to 3000 MHz
B3 to 30 MHz
C30 to 300 MHz
D300 kHz to 3 MHz

2. - E1A14

Except in some parts of Alaska, what is the maximum power permitted on the 630 meter band?

SelectAnswer
A100 watts PEP
B5 watts EIRP
C50 watts PEP
D1 watt EIRP

3. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

SelectAnswer
AYou must file an Environmental Impact Statement with the EPA before construction begins
BYou must obtain a construction permit from the airport zoning authority
CYou may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of the FCC rules
DYou must submit engineering drawings to the FAA

4. - E1C02

Which of the following types of communications may be transmitted to amateur stations in foreign countries?

SelectAnswer
ABusiness-related messages for non-profit organizations
BMessages intended for users of the maritime satellite service
CCommunications incidental to the purpose of the amateur service and remarks of a personal nature
DAll these choices are correct

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

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

6. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

SelectAnswer
ARevocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
BA fine of up to $1000 per occurrence
CAll these choices are correct
DA sentence of up to one year in prison

7. - E1F07

When may an amateur station send a message to a business?

SelectAnswer
AWhen the control operator is employed by the FCC or another government agency
BWhen transmitting international third-party communications
CWhen the total money involved does not exceed $25
DWhen neither the amateur nor his or her employer has a pecuniary interest in the communications

8. - E2A07

Which of the following types of signals can be relayed through a linear transponder?

SelectAnswer
ASSB and SSTV
BFM and CW
CPSK and packet
DAll these choices are correct

9. - E2B04

How is color information sent in analog SSTV?

SelectAnswer
AColor is sent in a color burst at the end of each line
BColor is amplitude modulated on the frequency modulated intensity signal
CColor lines are sent sequentially
DColor information is sent on a 2.8 kHz subcarrier

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

11. - E2D01

Which of the following digital modes is designed for meteor scatter communications?

SelectAnswer
AWSPR
BHellschreiber
CAPRS
DMSK144

12. - E2E07

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

SelectAnswer
AYour transmit frequency is incorrect
BAnother station you are unable to hear is using the frequency
CAll these choices are correct
DThe protocol version you are using is not supported by the digital station

13. - E3A14

What is meant by circularly polarized electromagnetic waves?

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

14. - E3B01

What is transequatorial propagation?

SelectAnswer
APropagation between a point on the equator and its antipodal point
BPropagation between points located on the magnetic equator
CPropagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
DPropagation between points at the same latitude

15. - E3C15

What might be indicated by a sudden rise in radio background noise across a large portion of the HF spectrum?

SelectAnswer
ALong-path propagation is likely
BA temperature inversion has occurred
CIncreased transequatorial propagation is likely
DA solar flare has occurred

16. - E4A06

What is the effect of aliasing on a digital oscilloscope caused by setting the time base too slow?

SelectAnswer
AAll signals will have a DC offset
BExcessive blanking occurs, which prevents display of the signal
CCalibration of the vertical scale is no longer valid
DA false, jittery low-frequency version of the signal is displayed

17. - E4B09

What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?

SelectAnswer
AThe transmitter is not properly neutralized
BThere is an impedance mismatch between the antenna and feed line
CThere is more power going into the antenna
DThere is possibly a short to ground in the feed line

18. - E4C02

Which of the following receiver circuits can be effective in eliminating interference from strong out-of-band signals?

SelectAnswer
AA narrow IF filter
BA properly adjusted product detector
CA notch filter
DA front-end filter or pre-selector

19. - E4D11

Why are odd-order intermodulation products, created within a receiver, of particular interest compared to other products?

SelectAnswer
AOdd-order products of two signals in the band of interest are also likely to be within the band
BOdd-order products are an indication of poor image rejection
COdd-order intermodulation produces three products for every input signal within the band of interest
DOdd-order products overload the IF filters

20. - E4E09

What undesirable effect can occur when using an IF noise blanker?

SelectAnswer
AThe audio frequency bandwidth of the received signal might be compressed
BFM signals can no longer be demodulated
CReceived audio in the speech range might have an echo effect
DNearby signals may appear to be excessively wide even if they meet emission standards

21. - E5A08

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

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

22. - E5B06

What is susceptance?

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

23. - E5C04

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

SelectAnswer
ARectangular coordinates
BMaidenhead grid
CFaraday grid
DElliptical coordinates

24. - E5D10

How can the true power be determined in an AC circuit where the voltage and current are out of phase?

SelectAnswer
ABy multiplying the apparent power by the power factor
BBy multiplying the reactive power by the power factor
CBy dividing the reactive power by the power factor
DBy dividing the apparent power by the power factor

25. - E6A01

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

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

26. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

SelectAnswer
ALonger carrier retention time
BLess forward voltage drop
CMore constant reverse avalanche voltage
DMuch higher reverse voltage breakdown

27. - E6C11

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

SelectAnswer
A5
B4
C6
D2

28. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

SelectAnswer
AToroidal cores confine most of the magnetic field within the core material
BToroidal cores have lower Q characteristics
CToroidal cores make it easier to couple the magnetic energy into other components
DToroidal cores exhibit greater hysteresis

29. - E6E11

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

SelectAnswer
APackage mounts in a direct inverted position
BA total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
CLow leakage doubly insulated package
DTwo chips in each package (Dual In Package)

30. - E6F09

What is the efficiency of a photovoltaic cell?

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

31. - E7A04

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

SelectAnswer
A2
B1
C4
D8

32. - E7B11

In Figure E7-1, what is the purpose of R3?

SelectAnswer
AEmitter bypass
BSelf bias
CFixed bias
DOutput load resistor

33. - E7C08

Which of the following factors has the greatest effect on the bandwidth and response shape of a crystal ladder filter?

SelectAnswer
AThe gain of the RF stage preceding the filter
BThe DC voltage applied to the quartz crystal
CThe amplitude of the signals passing through the filter
DThe relative frequencies of the individual crystals

34. - E7D15

What is the purpose of a step-start circuit in a high-voltage power supply?

SelectAnswer
ATo allow for remote control of the power supply
BTo compensate for variations of the incoming line voltage
CTo allow the filter capacitors to charge gradually
DTo provide a dual-voltage output for reduced power applications

35. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

SelectAnswer
ATo reduce impulse noise reception
BFor higher efficiency
CTo remove third-order distortion products
DFor compatibility with transmitters using phase modulation

36. - E7F04

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

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

37. - E7G02

What is ringing in a filter?

SelectAnswer
AA reduction in high frequency response
BPartial cancellation of the signal over a range of frequencies
CAn echo caused by a long time delay
DUndesired oscillations added to the desired signal

38. - E7H02

What is a microphonic?

SelectAnswer
AAn IC used for amplifying microphone signals
BChanges in oscillator frequency due to mechanical vibration
CExcess loading of the microphone by an oscillator
DDistortion caused by RF pickup on the microphone cable

39. - E8A09

How many different input levels can be encoded by an analog-to-digital converter with 8-bit resolution?

SelectAnswer
A256
B256 divided by the gain of the input amplifier
C8 multiplied by the gain of the input amplifier
D8

40. - E8B10

What is frequency division multiplexing?

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

41. - E8C07

What is the bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

SelectAnswer
A4.8 kHz
B15.36 kHz
C9.6 kHz
D5.76 kHz

42. - E8D05

What is the most common method of reducing key clicks?

SelectAnswer
AIncrease keying waveform rise and fall times
BHigh-pass filters at the transmitter output
CReduce keying waveform rise and fall times
DLow-pass filters at the transmitter output

43. - E9A07

What is the effective isotropic radiated power of a repeater station with 200 watts transmitter power output, 2 dB feed line loss, 2.8 dB duplexer loss, 1.2 dB circulator loss, and 7 dBi antenna gain?

SelectAnswer
A252 watts
B159 watts
C632 watts
D63.2 watts

44. - E9B04

What is the front-to-back ratio of the radiation pattern shown in Figure E92?

SelectAnswer
A3 dB
B38 dB
C28 dB
D15 dB

45. - E9C04

What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

SelectAnswer
AThe vertical angle increases
BThe lobes align more in the direction of the wire
CThe front-to-back ratio decreases
DThe lobes become more perpendicular to the wire

46. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

SelectAnswer
ATo cancel capacitive reactance
BTo increase the SWR bandwidth
CTo lower the losses
DTo lower the Q

47. - E9E08

What is a use for a Wilkinson divider?

SelectAnswer
AIt divides the operating frequency of a transmitter signal so it can be used on a lower frequency band
BIt is used to feed low-impedance loads from a high-impedance source
CIt is used to feed high-impedance antennas from a low-impedance source
DIt is used to divide power equally between two 50-ohm loads while maintaining 50-ohm input impedance

48. - E9F02

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

SelectAnswer
AThe line length
BThe center conductor resistivity
CThe termination impedance
DDielectric materials used in the line

49. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

SelectAnswer
AThe voltage axis
BThe resistance axis
CThe current axis
DThe reactance axis

50. - E9H02

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

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

Figure E6-3

Figure E7-1

Figure E9-3