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

2. - E1A01

Which of the following carrier frequencies is illegal for LSB AFSK emissions on the 17 meter band RTTY and data segment of 18.068 to 18.110 MHz?

SelectAnswer
A18.100 MHz
B18.068 MHz
C18.110 MHz
D18.107 MHz

3. - E1B01

Which of the following constitutes a spurious emission?

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

4. - E1C13

What notifications must be given before transmitting on the 630 meter or 2200 meter bands?

SelectAnswer
AOperators must inform the FAA of their intent to operate, giving their call sign and distance to the nearest runway
BOperators must inform the Utilities Technology Council (UTC) of their call sign and coordinates of the station
CAn environmental impact statement must be filed with the Department of the Interior
DA special endorsement must be requested from the FCC

5. - E1D08

Which VHF amateur bands have frequencies authorized for space stations?

SelectAnswer
A2 meters
B6 meters, 2 meters, and 1.25 meters
C6 meters and 2 meters
D2 meters and 1.25 meters

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
CPhotocopy all examination documents and forward them to the FCC for processing
DThree VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements

7. - E1F08

Which of the following types of amateur station communications are prohibited?

SelectAnswer
ACommunications in a language other than English
BCommunications that have religious content
CCommunications transmitted for hire or material compensation, except as otherwise provided in the rules
DCommunications that have political content, except as allowed by the Fairness Doctrine

8. - E2A10

What type of satellite appears to stay in one position in the sky?

SelectAnswer
AGeostationary
BHEO
CLEO
DGeomagnetic

9. - E2B11

What is the function of the Vertical Interval Signaling (VIS) code sent as part of an SSTV transmission?

SelectAnswer
ATo provide vertical synchronization
BTo identify the SSTV mode being used
CTo lock the color burst oscillator in color SSTV images
DTo identify the call sign of the station transmitting

10. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

SelectAnswer
ARepeater contacts between U.S. club members
BContacts using tactical call signs
CSpecial event contacts between stations in the U.S.
DContacts between a U.S. station and a non-U.S. station

11. - E2D10

How can an APRS station be used to help support a public service communications activity?

SelectAnswer
AAn APRS station with a Global Positioning System unit can automatically transmit information to show a mobile station's position during the event
BAPRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
CAn APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
DAll these choices are correct

12. - E2E13

Which of these digital modes has the fastest data throughput under clear communication conditions?

SelectAnswer
AAMTOR
B300 baud packet
C170 Hz shift, 45 baud RTTY
DPSK31

13. - E3A05

Tropospheric propagation of microwave signals often occurs in association with what phenomenon?

SelectAnswer
ALightning discharges
BSprites and jets
CGrayline
DWarm and cold fronts

14. - E3B10

Why is chordal hop propagation desirable?

SelectAnswer
AThe MUF for chordal hop propagation is much lower than for normal skip propagation
BThe signal experiences less loss compared to multi-hop using Earth as a reflector
CSignals travel faster along ionospheric chords
DAtmospheric noise is lower in the direction of chordal hop propagation

15. - E3C06

By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

SelectAnswer
ABy approximately 50 percent of the distance
BBy approximately twice the distance
CBy approximately four times the distance
DBy approximately 15 percent of the distance

16. - E4A03

Which of the following test instruments is used to display spurious signals and/or intermodulation distortion products generated by an SSB transmitter?

SelectAnswer
AA wattmeter
BA time-domain reflectometer
CA spectrum analyzer
DA logic analyzer

17. - E4B04

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

SelectAnswer
AS21
BS12
CS22
DS11

18. - E4C15

What is reciprocal mixing?

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

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 overload the IF filters
COdd-order products are an indication of poor image rejection
DOdd-order intermodulation produces three products for every input signal within the band of interest

20. - E4E11

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

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

21. - E5A11

What is the half-power bandwidth of a resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

SelectAnswer
A315.6 Hz
B47.3 kHz
C23.67 kHz
D157.8 Hz

22. - E5B05

What happens to the magnitude of a pure reactance when it is converted to a susceptance?

SelectAnswer
AIt becomes the reciprocal
BIt is unchanged
CIt is shifted by 90 degrees
DThe sign is reversed

23. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

SelectAnswer
AA positive phase angle
BA negative magnitude
CA positive magnitude
DA negative phase angle

24. - E5D04

Why are short connections used at microwave frequencies?

SelectAnswer
ATo reduce noise figure
BTo increase compensating capacitance
CTo reduce phase shift along the connection
DTo increase neutralizing resistance

25. - E6A11

In Figure E6-1, what is the schematic symbol for a P-channel junction FET?

SelectAnswer
A3
B2
C6
D1

26. - E6B06

Which of the following is a common use of a Schottky diode?

SelectAnswer
AAs a rectifier in high current power supplies
BAs a variable capacitance in an automatic frequency control circuit
CAs a VHF/UHF mixer or detector
DAs a constant voltage reference in a power supply

27. - E6C04

Which of the following is an advantage of BiCMOS logic?

SelectAnswer
AIt has the high input impedance of CMOS and the low output impedance of bipolar transistors
BAll these choices are correct
CIt is immune to electrostatic damage
DIts simplicity results in much less expensive devices than standard CMOS

28. - E6D10

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

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

29. - E6E04

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

SelectAnswer
A450 ohms
B10 ohms
C300 ohms
D50 ohms

30. - E6F10

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

SelectAnswer
ACopper oxide
BCadmium Sulfide
CSelenium
DSilicon

31. - E7A07

What logical operation does a NAND gate perform?

SelectAnswer
AIt produces logic 0 at its output only when all inputs are logic 1
BIt produces logic 0 at its output if some but not all inputs are logic 1
CIt produces logic 0 at its output only when all inputs are logic 0
DIt produces logic 1 at its output only when all inputs are logic 1

32. - E7B11

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

SelectAnswer
AFixed bias
BSelf bias
CEmitter bypass
DOutput load resistor

33. - E7C06

What are the distinguishing features of an elliptical filter?

SelectAnswer
AGradual passband rolloff with extreme stop band ripple
BExtremely sharp cutoff with one or more notches in the stop band
CExtremely flat response over its pass band with gradually rounded stop band corners
DGradual passband rolloff with minimal stop band ripple

34. - E7D08

What type of circuit is shown in Figure E7-2?

SelectAnswer
ALinear voltage regulator
BGrounded emitter amplifier
CSwitching voltage regulator
DMonostable multivibrator

35. - E7E07

What is meant by the term "baseband" in radio communications?

SelectAnswer
AThe unmodulated bandwidth of the transmitted signal
BThe frequency range occupied by a message signal prior to modulation
CThe basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
DThe lowest frequency band that the transmitter or receiver covers

36. - E7F04

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

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

37. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 3300 ohms and RF is 47 kilohms?

SelectAnswer
A14
B28
C7
D0.07

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 diode-switching matrix synthesizer
DA phase-locked loop synthesizer

39. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

SelectAnswer
AAll these choices are correct
BVery low power consumption decreases frequency drift
CImmunity to out-of-sequence coding reduces spurious responses
DVery high speed allows digitizing high frequencies

40. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

SelectAnswer
A6000
B3
C1/3
D2000

41. - E8C12

What factors affect the bandwidth of a transmitted CW signal?

SelectAnswer
AKeying speed and shape factor (rise and fall time)
BAll these choices are correct
CIF bandwidth and Q
DModulation index and output power

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
ATotal resistance divided by radiation resistance
BEffective radiated power divided by transmitter output
CRadiation resistance divided by total resistance
DRadiation resistance divided by transmission resistance

44. - E9B10

What is the principle of a Method of Moments analysis?

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

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 become more perpendicular to the wire
CThe lobes align more in the direction of the wire
DThe front-to-back ratio decreases

46. - E9D03

Where should a high Q loading coil be placed to minimize losses in a shortened vertical antenna?

SelectAnswer
AAs low as possible on the vertical radiator
BAs close to the transmitter as possible
CAt a voltage node
DNear the center of the vertical radiator

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

48. - E9F02

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

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

49. - E9G07

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

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

50. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

SelectAnswer
AIts overall length must not exceed 1/4 wavelength
BIt must be mounted more than 1 wavelength above ground
CIt should be configured as a four-sided loop
DIt should be one or more wavelengths long

Figure E6-1

Figure E7-1

Figure E7-2

Figure E7-3

Figure E9-3