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

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1. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

SelectAnswer
AOnly the most powerful transmitter
BOnly commercial transmitters
CEach transmitter that produces 5 percent or more of its MPE limit in areas where the total MPE limit is exceeded.
DEach transmitter operating with a duty cycle greater than 50 percent

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

3. - E1B02

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
A10 kHz
B15 kHz
C20 kHz
D3 kHz

4. - E1C14

How long must an operator wait after filing a notification with the Utilities Technology Council (UTC) before operating on the 2200 meter or 630 meter band?

SelectAnswer
AOperations may commence immediately, and may continue unless interference is reported by the UTC
BOperators may not operate until a test signal has been transmitted in coordination with the local power company
COperators may operate after 30 days, providing they have not been told that their station is within 1 km of PLC systems using those frequencies
DOperators must not operate until approval is received

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. - 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
BAll these choices are correct
CA fine of up to $1000 per occurrence
DA sentence of up to one year in prison

7. - E1F10

Who may be the control operator of an auxiliary station?

SelectAnswer
AAny licensed amateur operator
BOnly Technician, General, Advanced or Amateur Extra Class operators
COnly Amateur Extra Class operators
DOnly General, Advanced or Amateur Extra Class operators

8. - E2A02

Which of the following occurs when a satellite is using an inverting linear transponder?

SelectAnswer
ADoppler shift is reduced because the uplink and downlink shifts are in opposite directions
BAll these choices are correct
CSignal position in the band is reversed
DUpper sideband on the uplink becomes lower sideband on the downlink, and vice versa

9. - E2B04

How is color information sent in analog SSTV?

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

10. - E2C04

Which of the following frequencies are sometimes used for amateur radio mesh networks?

SelectAnswer
ACable TV channels 41 through 43
BFrequencies shared with various unlicensed wireless data services
CHF frequencies where digital communications are permitted
DThe 60 meter band channel centered on 5373 kHz

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
BShort transmissions with rapidly repeated call signs and signal reports
CUse of special digital modes
DAll these choices are correct

12. - E2E12

How do ALE stations establish contact?

SelectAnswer
AALE radios activate when they hear their signal echoed by back scatter
BALE radios monitor an internet site for the frequency they are being paged on
CALE radios send a constant tone code to establish a frequency for future use
DALE constantly scans a list of frequencies, activating the radio when the designated call sign is received

13. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

SelectAnswer
AWhen the MUF is above 30 MHz
BWhen the moon is at apogee
CWhen the moon is full
DWhen the moon is at perigee

14. - E3B07

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

SelectAnswer
AThey become phase locked
BThey are bent toward the magnetic poles
CThey become elliptically polarized
DThey become depolarized

15. - E3C10

What does the 304A solar parameter measure?

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

16. - E4A10

Which of the following displays multiple digital signal states simultaneously?

SelectAnswer
ANetwork analyzer
BModulation monitor
CLogic analyzer
DBit error rate tester

17. - E4B10

Which of the following methods measures intermodulation distortion in an SSB transmitter?

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

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 notch filter
CA front-end filter or pre-selector
DA properly adjusted product detector

19. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

SelectAnswer
AA band-pass filter in the feed line between the transmitter and receiver
BA properly terminated circulator at the output of the repeater's transmitter
CUtilizing a Class C final amplifier
DUtilizing a Class D final amplifier

20. - E4E02

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

SelectAnswer
AAll these choices are correct
BIgnition noise
CPower line noise
DBroadband white noise

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 multiplied by the resistance
CReactance of either the inductance or capacitance divided by the resistance
DResistance divided by the reactance of either the inductance or capacitance

22. - E5B05

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

SelectAnswer
AThe sign is reversed
BIt is shifted by 90 degrees
CIt becomes the reciprocal
DIt is unchanged

23. - E5C11

Which point in Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and an 18-microhenry inductor at 3.505 MHz?

SelectAnswer
APoint 3
BPoint 1
CPoint 8
DPoint 7

24. - E5D11

What is the power factor of an RL circuit having a 60-degree phase angle between the voltage and the current?

SelectAnswer
A1.414
B0.866
C0.5
D1.73

25. - E6A01

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

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

26. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

SelectAnswer
ATunnel diode
BVaractor diode
CSilicon-controlled rectifier
DZener diode

27. - E6C11

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

SelectAnswer
A2
B4
C5
D6

28. - E6D05

What is one reason for using ferrite cores rather than powdered iron in an inductor?

SelectAnswer
AFerrite toroids generally have better temperature stability
BFerrite toroids are easier to use with surface mount technology
CFerrite toroids generally require fewer turns to produce a given inductance value
DFerrite toroids generally have lower initial permeability

29. - E6E07

What type of transmission line is used for connections to MMICs?

SelectAnswer
AMicrostrip
BMiniature coax
CParallel wire
DCircular waveguide

30. - E6F10

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

SelectAnswer
ASelenium
BSilicon
CCopper oxide
DCadmium Sulfide

31. - E7A09

What logical operation is performed by an exclusive NOR gate?

SelectAnswer
AIt produces logic 1 at its output if only one input is logic 1
BIt produces logic 1 at its output only if all inputs are logic 1
CIt produces logic 0 at its output only if all inputs are logic 0
DIt produces logic 0 at its output if only one input is logic 1

32. - E7B03

Which of the following components form the output of a class D amplifier circuit?

SelectAnswer
AA temperature compensating load resistor to improve linearity
BA matched load resistor to prevent damage by switching transients
CA high-pass filter to compensate for low gain at low frequencies
DA low-pass filter to remove switching signal components

33. - E7C05

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

SelectAnswer
AA Butterworth filter
BA Chebyshev filter
CAn active LC filter
DA passive op-amp filter

34. - E7D11

What is the function of the pass transistor in a linear voltage regulator circuit?

SelectAnswer
AMaintains nearly constant output impedance over a wide range of load current
BProvides a stable input impedance over a wide range of source voltage
CMaintains nearly constant output voltage over a wide range of load current
DPermits a wide range of output voltage settings

35. - E7E03

What is a frequency discriminator stage in a FM receiver?

SelectAnswer
AA circuit for detecting FM signals
BAn FM generator circuit
CAn automatic band-switching circuit
DA circuit for filtering two closely adjacent signals

36. - E7F04

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

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

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. - E7H14

What is a phase-locked loop circuit?

SelectAnswer
AAn electronic circuit consisting of a precision push-pull amplifier with a differential input
BAn electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
CAn electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
DAn electronic circuit also known as a monostable multivibrator

39. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

SelectAnswer
A1 to 1
B100 to 1
C25 to 1
D2.5 to 1

40. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

SelectAnswer
A0.3
B3
C1000
D3000

41. - E8C06

What is the bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

SelectAnswer
A1.0 kHz
B0.5 kHz
C0.1 Hz
D0.3 kHz

42. - E8D05

What is the most common method of reducing key clicks?

SelectAnswer
AReduce keying waveform rise and fall times
BIncrease keying waveform rise and fall times
CHigh-pass filters at the transmitter output
DLow-pass filters at the transmitter output

43. - E9A06

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

SelectAnswer
A126 watts
B300 watts
C317 watts
D2000 watts

44. - E9B07

How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from a theoretical isotropic antenna, assuming each is driven by the same amount of power?

SelectAnswer
AThey are the same
BThe total amount of radiation from the directional antenna is stronger by its front-to-back ratio
CThe radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna
DThe total amount of radiation from the directional antenna is increased by the gain of the antenna

45. - E9C08

What is a folded dipole antenna?

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

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
BArrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
CStack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
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
BInsert a 1/2 wavelength piece of 300-ohm twinlead in series between the antenna terminals and the 50-ohm feed cable
CConnect a 1/2 wavelength shorted stub of 75-ohm cable in parallel with the 50-ohm cable where it attaches to the antenna
DConnect a 1/4-wavelength open stub of 300-ohm twinlead in parallel with the coaxial feed line where it connects to the antenna

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
AA capacitive reactance
BThe same as the characteristic impedance of the line
CAn inductive reactance
DZero

49. - E9G08

What is the process of normalization with regard to a Smith chart?

SelectAnswer
AReassigning prime center with regard to the reactance axis
BReassigning impedance values with regard to the prime center
CReassigning reactance values with regard to the resistance axis
DReassigning resistance values with regard to the reactance axis

50. - E9H11

What feature of a cardioid pattern antenna makes it useful for direction finding?

SelectAnswer
ABroadband response
BHigh radiation angle
CA very sharp single null
DA very sharp peak

Figure E5-1

Figure E6-3

Figure E7-3