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

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1. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

SelectAnswer
AIngestion of ozone gas from the cooling system
BBlood clotting from the intense magnetic field
CLocalized heating of the body from RF exposure in excess of the MPE limits
DHearing loss caused by high voltage corona discharge

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 FCC-issued amateur license
BAn unrestricted Radiotelephone Operator Permit
CAny amateur license with an FCC Marine or Aircraft endorsement
DOnly General Class or higher amateur licenses

3. - E1B11

What does PRB-1 require of regulations affecting amateur radio?

SelectAnswer
AReasonable accommodations of amateur radio must be made
BAmateur radio operations must be permitted in any private residence
CUse of wireless devices in a vehicle is exempt from regulation
DNo limitations may be placed on antenna size or placement

4. - E1C04

What is meant by IARP?

SelectAnswer
AThe internal amateur radio practices policy of the FCC
BAn international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
CA forecast of intermittent aurora radio propagation
DAn indication of increased antenna reflected power

5. - E1D06

What is the maximum permitted transmitter output power when operating a model craft by telecommand?

SelectAnswer
A5 watts
B1 watt
C100 watts
D2 watts

6. - E1E03

What is a Volunteer Examiner Coordinator?

SelectAnswer
AA person who has volunteered to administer amateur operator license examinations
BThe person who has entered into an agreement with the FCC to be the VE session manager
CAn organization that has entered into an agreement with the FCC to coordinate, prepare, and administer amateur operator license examinations
DA person who has volunteered to prepare amateur operator license examinations

7. - E1F04

Which of the following geographic descriptions approximately describes "Line A"?

SelectAnswer
AA line roughly parallel to and east of the U.S. Pacific coastline
BA line roughly parallel to and west of the U.S. Atlantic coastline
CA line roughly parallel to and north of the border between the U.S. and Mexico
DA line roughly parallel to and south of the border between the U.S. and Canada

8. - E2A12

What is the purpose of digital store-and-forward functions on an amateur radio satellite?

SelectAnswer
ATo relay messages between satellites
BTo store digital messages in the satellite for later download by other stations
CTo delay download of telemetry between satellites
DTo upload operational software for the transponder

9. - E2B12

What signals SSTV receiving software to begin a new picture line?

SelectAnswer
AA two-tone signal
BSpecific tone frequencies
CElapsed time
DSpecific tone amplitudes

10. - E2C10

Why might a DX station state that they are listening on another frequency?

SelectAnswer
ABecause the DX station may be transmitting on a frequency that is prohibited to some responding stations
BTo improve operating efficiency by reducing interference
CAll these choices are correct
DTo separate the calling stations from the DX station

11. - E2D02

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

SelectAnswer
AShort transmissions with rapidly repeated call signs and signal reports
BUse of special digital modes
CAll these choices are correct
D15-second timed transmission sequences with stations alternating based on location

12. - E2E02

What do the letters FEC mean as they relate to digital operation?

SelectAnswer
AFirst Error Correction
BFatal Error Correction
CFinal Error Correction
DForward Error Correction

13. - E3A09

Which of the following frequency ranges is most suited for meteor scatter communications?

SelectAnswer
A28 MHz - 148 MHz
B220 MHz - 450 MHz
C10 MHz - 14 MHz
D1.8 MHz - 1.9 MHz

14. - E3B12

What is the primary characteristic of chordal hop propagation?

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

15. - E3C02

What is indicated by a rising A or K index?

SelectAnswer
AHigher levels of solar UV radiation
BIncreasing disruption of the geomagnetic field
CDecreasing disruption of the geomagnetic field
DAn increase in the critical frequency

16. - E4A10

Which of the following displays multiple digital signal states simultaneously?

SelectAnswer
ANetwork analyzer
BBit error rate tester
CLogic analyzer
DModulation monitor

17. - E4B02

What is the significance of voltmeter sensitivity expressed in ohms per volt?

SelectAnswer
AThe full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter
BWhen used as a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test
CWhen used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit
DWhen used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed

18. - E4C14

What transmit frequency might generate an image response signal in a receiver tuned to 14.300 MHz and that uses a 455 kHz IF frequency?

SelectAnswer
A14.755 MHz
B15.210 MHz
C13.845 MHz
D14.445 MHz

19. - E4D05

What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

SelectAnswer
A173.35 MHz and 139.40 MHz
B146.34 MHz and 146.61 MHz
C146.10 MHz and 147.30 MHz
D146.88 MHz and 146.34 MHz

20. - E4E02

Which of the following types of noise can often be reduced with a digital signal processing noise filter?

SelectAnswer
ABroadband white noise
BIgnition noise
CPower line noise
DAll these choices are correct

21. - E5A03

What is the magnitude of the impedance of a series RLC circuit at resonance?

SelectAnswer
AApproximately equal to inductive reactance
BHigh, as compared to the circuit resistance
CApproximately equal to circuit resistance
DApproximately equal to capacitive reactance

22. - E5B05

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

SelectAnswer
AIt is shifted by 90 degrees
BThe sign is reversed
CIt is unchanged
DIt becomes the reciprocal

23. - E5C07

Where is the impedance of a pure resistance plotted on rectangular coordinates?

SelectAnswer
AOn a horizontal line, offset vertically above the horizontal axis
BOn a line through the origin, slanted at 45 degrees
COn the vertical axis
DOn the horizontal axis

24. - E5D10

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

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

25. - 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 has no current flow between source and drain when no gate voltage is applied
DAn FET that exhibits a current flow between source and drain when no gate voltage is applied

26. - E6B09

What is a common use for point-contact diodes?

SelectAnswer
AAs a high-voltage rectifier
BAs an RF detector
CAs a constant current source
DAs a constant voltage source

27. - E6C03

What is tri-state logic?

SelectAnswer
ALow-power logic devices designed to operate at 3 volts
BProprietary logic devices manufactured by Tri-State Devices
CLogic devices that utilize ternary math
DLogic devices with 0, 1, and high-impedance output states

28. - E6D03

Which of the following is an aspect of the piezoelectric effect?

SelectAnswer
AGeneration of electrical energy in the presence of light
BMechanical deformation of material by the application of a voltage
CIncreased conductivity in the presence of light
DMechanical deformation of material by the application of a magnetic field

29. - E6E01

Why is gallium arsenide (GaAs) useful for semiconductor devices operating at UHF and higher frequencies?

SelectAnswer
AHigher electron mobility
BLower transconductance
CHigher noise figures
DLower junction voltage drop

30. - E6F04

What is the photovoltaic effect?

SelectAnswer
AThe conversion of light to electrical energy
BThe tendency of a battery to discharge when exposed to light
CThe conversion of voltage to current when exposed to light
DThe conversion of electrical energy to mechanical energy

31. - E7A01

Which circuit is bistable?

SelectAnswer
AAn OR gate
BA flip-flop
CAn AND gate
DA bipolar amplifier

32. - E7B15

What is one way to prevent thermal runaway in a bipolar transistor amplifier?

SelectAnswer
ANeutralization
BUse a resistor in series with the emitter
CAll these choices are correct
DSelect transistors with high beta

33. - E7C10

Which of the following filters would be the best choice for use in a 2 meter band repeater duplexer?

SelectAnswer
AAn L-C filter
BA crystal filter
CA DSP filter
DA cavity filter

34. - E7D10

What is the primary reason that a high-frequency switching type high-voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

SelectAnswer
AIt uses a large power factor compensation capacitor to recover power from the unused portion of the AC cycle
BThe high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
CIt uses a diode bridge rectifier for increased output
DThe inverter design does not require any output filtering

35. - E7E02

What is the function of a reactance modulator?

SelectAnswer
ATo produce AM signals by using an electrically variable resistance
BTo produce PM or FM signals by using an electrically variable inductance or capacitance
CTo produce AM signals by using an electrically variable inductance or capacitance
DTo produce PM signals by using an electrically variable resistance

36. - E7F07

What function is performed by a Fast Fourier Transform?

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

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-0.23 volts
B2.3 volts
C0.23 volts
D-2.3 volts

38. - E7H05

How is positive feedback supplied in a Pierce oscillator?

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

39. - E8A02

Which of the following is a type of analog-to-digital conversion?

SelectAnswer
ASuccessive approximation
BLevel shifting
CPhase reversal
DHarmonic regeneration

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
A47
B2.14
C0.214
D0.47

41. - E8C04

What technique minimizes the bandwidth of a PSK31 signal?

SelectAnswer
AUse of sinusoidal data pulses
BZero-sum character encoding
CUse of trapezoidal data pulses
DReed-Solomon character encoding

42. - E8D06

What is the advantage of including parity bits in ASCII characters?

SelectAnswer
AFaster transmission rate
BSome types of errors can be detected
CForeign language characters can be sent
DThe signal can overpower interfering signals

43. - E9A12

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 6 dB gain over an isotropic antenna?

SelectAnswer
A2.79 dB
B8.15 dB
C3.85 dB
D6.0 dB

44. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the beamwidth?

SelectAnswer
A30 degrees
B75 degrees
C25 degrees
D50 degrees

45. - E9C08

What is a folded dipole antenna?

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

46. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

SelectAnswer
AStack two Yagis fed in phase to form an array with the respective elements in parallel planes
BStack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
CArrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
DArrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase

47. - E9E10

Which of these choices is an effective way to match an antenna with a 100-ohm feed point impedance to a 50-ohm coaxial cable feed line?

SelectAnswer
AInsert a 1/4-wavelength piece of 75-ohm coaxial cable transmission line in series between the antenna terminals and the 50-ohm feed cable
BConnect a 1/4-wavelength open stub of 300-ohm twinlead in parallel with the coaxial feed line where it connects to the antenna
CConnect a 1/2 wavelength shorted stub of 75-ohm cable in parallel with the 50-ohm cable where it attaches to the antenna
DInsert a 1/2 wavelength piece of 300-ohm twinlead in series between the antenna terminals and the 50-ohm feed cable

48. - E9F10

What impedance does a 1/8-wavelength transmission line present to a generator when the line is shorted at the far end?

SelectAnswer
AZero
BA capacitive reactance
CThe same as the characteristic impedance of the line
DAn inductive reactance

49. - E9G04

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

SelectAnswer
AReactance and voltage
BVoltage and impedance
CResistance and reactance
DResistance and voltage

50. - E9H10

How can the output voltage of a multiple-turn receiving loop antenna be increased?

SelectAnswer
ABy winding adjacent turns in opposing directions
BBy reducing the permeability of the loop shield
CBy utilizing high impedance wire for the coupling loop
DBy increasing the number of turns and/or the area

Figure E7-3

Figure E9-1