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US Amateur Radio - Amateur Extra (Element 4, 2016-2020) Practice Test

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1. - 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
AOnly a person with an FCC Marine Radio
BAny person named in an amateur station license grant or a person holding an unrestricted Radiotelephone Operator Permit
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

2. - E1B01

Which of the following constitutes a spurious emission?

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

3. - E1C01

What is a remotely controlled station?

SelectAnswer
AA station operated away from its regular home location
BA station operating under automatic control
CA station controlled by someone other than the licensee
DA station controlled indirectly through a control link

4. - E1D03

What is a telecommand station in the amateur satellite service?

SelectAnswer
AAn amateur station located more than 50 km above the Earth's surface
BAn amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites
CAn amateur station that transmits telemetry consisting of measurements of upper atmosphere
DAn amateur station that transmits communications to initiate, modify or terminate functions of a space station

5. - E1E09

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

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

6. - E1F11

Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

SelectAnswer
AIt must be capable of external RF switching between its input and output networks
BIt must exhibit a gain of 0 dB or less over its full output range
CIt must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power
DIt must produce full legal output when driven by not more than 5 watts of mean RF input power

7. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

SelectAnswer
AAn isotropic antenna
BA circularly polarized antenna
CA log-periodic dipole array
DA linearly polarized antenna

8. - E2B10

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
B10 KHz
C20 KHz
D3 KHz

9. - E2C05

What is the function of a DX QSL Manager?

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

10. - E2D04

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 relay messages between satellites
CTo upload operational software for the transponder
DTo delay download of telemetry between satellites

11. - E2E09

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

SelectAnswer
APACTOR
BPSK31
CRTTY
DMT63

12. - E3A07

Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?

SelectAnswer
AForests
BUrban areas
CBodies of water
DMountain ranges

13. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

SelectAnswer
A1000 miles
B2500 miles
C5000 miles
D7500 miles

14. - E3C04

What does the value of Bz (B sub Z) represent?

SelectAnswer
ADuration of long-delayed echoes
BDirection and strength of the interplanetary magnetic field
CGeomagnetic field stability
DCritical frequency for vertical transmissions

15. - E4A11

Which of the following is good practice when using an oscilloscope probe?

SelectAnswer
AKeep the signal ground connection of the probe as short as possible
BAll of these choices are correct
CNever use a high impedance probe to measure a low impedance circuit
DNever use a DC-coupled probe to measure an AC circuit

16. - E4B10

Which of the following describes a method to measure intermodulation distortion in an SSB transmitter?

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

17. - E4C13

How does a narrow-band roofing filter affect receiver performance?

SelectAnswer
AIt improves dynamic range by attenuating strong signals near the receive frequency
BIt improves intelligibility by using low Q circuitry to reduce ringing
CAll of these choices are correct
DIt improves sensitivity by reducing front end noise

18. - E4D10

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

SelectAnswer
AThe receiver can tolerate signals up to 40 dB above the noise floor without producing third-order intermodulation products
BA pair of 40 dBm signals will theoretically generate a third-order intermodulation product with the same level as the input signals
CA pair of 1 mW input signals will produce a third-order intermodulation product which is 40 dB stronger than the input signal
DSignals less than 40 dBm will not generate audible third-order intermodulation products

19. - E4E05

How can noise from an electric motor be suppressed?

SelectAnswer
ABy installing a bypass capacitor in series with the motor leads
BBy using a ground-fault current interrupter in the circuit used to power the motor
CBy installing a high pass filter in series with the motor's power leads
DBy installing a brute-force AC-line filter in series with the motor leads

20. - E5A10

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

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

21. - E5B02

What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

SelectAnswer
AOne time constant
BA discharge factor of one
CAn exponential discharge rate of one
DOne discharge period

22. - E5C08

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

SelectAnswer
APolar coordinates
BElliptical coordinates
CFaraday grid
DMaidenhead grid

23. - E5D07

What determines the strength of the magnetic field around a conductor?

SelectAnswer
AThe amount of current flowing through the conductor
BThe resistance divided by the current
CThe diameter of the conductor
DThe ratio of the current to the resistance

24. - E6A09

What is a depletion-mode FET?

SelectAnswer
AAny FET for which holes are the majority carriers
BAny FET without a channel
CAn FET that exhibits a current flow between source and drain when no gate voltage is applied
DAn FET that has no current flow between source and drain when no gate voltage is applied

25. - E6B10

In Figure E6-3, what is the schematic symbol for a light-emitting diode?

SelectAnswer
A7
B5
C1
D6

26. - E6C02

What happens when the level of a comparator's input signal crosses the threshold?

SelectAnswer
AThe feedback loop becomes unstable
BThe comparator changes its output state
CThe IC input can be damaged
DThe comparator enters latch-up

27. - E6D14

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

SelectAnswer
ABrass
BPowdered-iron
CFerrite
DCeramic

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

SelectAnswer
AGround-plane construction
BWave-soldering construction
CPoint-to-point construction
DMicrostrip construction

29. - E6F06

Which of these materials is affected the most by photoconductivity?

SelectAnswer
AA crystalline semiconductor
BA heavy metal
CA liquid semiconductor
DAn ordinary metal

30. - E7A10

What is a truth table?

SelectAnswer
AA table of logic symbols that indicate the high logic states of an op-amp
BA table of logic symbols that indicate the logic states of an op-amp
CA diagram showing logic states when the digital device output is true
DA list of inputs and corresponding outputs for a digital device

31. - E7B13

In Figure E7-2, what is the purpose of R?

SelectAnswer
AFixed bias
BVoltage regulation
CEmitter load
DCollector load

32. - E7C14

Which mode is most affected by non-linear phase response in a receiver IF filter?

SelectAnswer
AVideo
BDigital
CSingle-Sideband voice
DMeteor scatter

33. - E7D06

What is the purpose of Q1 in the circuit shown in Figure E7-3?

SelectAnswer
AIt provides a constant load for the voltage source
BIt increases the current-handling capability of the regulator
CIt provides D1 with current
DIt provides negative feedback to improve regulation

34. - E7E03

How does an analog phase modulator function?

SelectAnswer
ABy varying the tuning of an amplifier tank circuit to produce PM signals
BBy varying the tuning of a microphone preamplifier to produce AM signals
CBy varying the tuning of an amplifier tank circuit to produce AM signals
DBy varying the tuning of a microphone preamplifier to produce PM signals

35. - E7F07

What function can a Fast Fourier Transform perform?

SelectAnswer
AConverting digital signals from the time domain to the frequency domain
BConverting analog signals to digital form
CConverting 8-bit data to 16 bit data
DConverting digital signals to analog form

36. - E7G12

What is an integrated circuit operational amplifier?

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

37. - E7H02

Which describes a microphonic?

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

38. - E8A03

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

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

39. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

SelectAnswer
AExtremely low-power contacts
BOFDM signals are not allowed on amateur bands
CHigh speed digital modes
DEME

40. - E8C02

What is the definition of symbol rate in a digital transmission?

SelectAnswer
AThe number of control characters in a message packet
BThe duration of each bit in a message sent over the air
CThe number of characters carried per second by the station-to-station link
DThe rate at which the waveform of a transmitted signal changes to convey information

41. - E8D02

What spread spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?

SelectAnswer
ADirect sequence
BFrequency hopping
CPhase compandored spread spectrum
DBinary phase-shift keying

42. - E9A15

What is the effective radiated power relative to a dipole of a repeater station with 150 watts transmitter power output, 2 dB feed line loss, 2.2 dB duplexer loss, and 7 dBd antenna gain?

SelectAnswer
A1977 watts
B78.7 watts
C420 watts
D286 watts

43. - E9B10

What is the principle of a Method of Moments analysis?

SelectAnswer
AA wire is modeled as a series of segments, each having a uniform value of current
BA wire is modeled as a single sine-wave current generator
CA wire is modeled as a series of segments, each having a distinct value of voltage across it
DA wire is modeled as a series of points, each having a distinct location in space

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

SelectAnswer
AIt changes the impedance angle of the matching network
BIt reduces losses in the radiating portion of the antenna
CIt causes increased SWR
DIt reduces low-angle radiation

45. - E9D01

How does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

SelectAnswer
AGain increases by 6 dB
BGain is multiplied by 0.707
CGain does not change
DGain increases by 3 dB

46. - 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 delta matching system
CThe stub matching system
DThe omega matching system

47. - E9F14

What impedance does a 1/2 wavelength transmission line present to a generator when the line is shorted at the far end?

SelectAnswer
AVery high impedance
BThe same as the characteristic impedance of the line
CThe same as the output impedance of the generator
DVery low impedance

48. - E9G04

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

SelectAnswer
AVoltage and impedance
BResistance and voltage
CResistance and reactance
DReactance and voltage

49. - 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
BLow loss coax transmission line is essential for good performance
CAtmospheric noise is so high that gain over a dipole is not important
DAll of these choices are correct

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

SelectAnswer
AMica
BBeryllium Oxide
CUranium Hexafluoride
DZinc oxide

Figure E6-3

Figure E7-2

Figure E7-3