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

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1. - E0A08

What does SAR measure?

SelectAnswer
AThe rate at which RF energy is absorbed by the body
BSignal Amplification Rating
CThe rate of RF energy reflected from stationary terrain
DSynthetic Aperture Ratio of the human body

2. - E1A08

If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

SelectAnswer
AThe control operator of the packet bulletin board station
BThe control operator of the originating station
CThe control operators of all the stations in the system
DThe control operators of all the stations in the system not authenticating the source from which they accept communications

3. - E1B05

What is the National Radio Quiet Zone?

SelectAnswer
AAn area surrounding the National Radio Astronomy Observatory
BAn area in Puerto Rico surrounding the Arecibo Radio Telescope
CAn area in New Mexico surrounding the White Sands Test Area
DAn area in Florida surrounding Cape Canaveral

4. - E1C07

At what level below a signal's mean power level is its bandwidth determined according to FCC rules?

SelectAnswer
A23 dB
B26 dB
C6 dB
D3 dB

5. - E1D03

What is a space telecommand station?

SelectAnswer
AAn amateur station located on the surface of the Earth for communication with other Earth stations by means of Earth satellites
BAn amateur station located in a satellite or a balloon more than 50 kilometers above the surface of the Earth
CAn amateur station that transmits communications to initiate, modify or terminate functions of a space station
DAn amateur station that receives telemetry from a satellite or balloon more than 50 kilometers above the surface of the Earth

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. - E1F08

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

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

8. - E2A05

What do the letters in a satellite's mode designator specify?

SelectAnswer
AThe location of the ground control station
BThe uplink and downlink frequency ranges
CThe polarization of uplink and downlink signals
DPower limits for uplink and downlink transmissions

9. - E2B02

How many horizontal lines make up a fast-scan (NTSC) television frame?

SelectAnswer
A30
B525
C1080
D60

10. - E2C02

Which of the following best describes the term self-spotting? in connection with HF contest operating?

SelectAnswer
AThe acceptable practice of manually posting the call signs of stations on a spotting network
BA manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
CThe often-prohibited practice of posting one's own call sign and frequency on a spotting network
DAn automatic method for rapidly zero beating or tuning to a station's frequency before calling that station

11. - E2D06

Which of the following describes a method of establishing EME contacts?

SelectAnswer
ATime synchronous transmissions alternately from each station
BJudging optimum transmission times by monitoring beacons reflected from the moon
CStoring and forwarding digital messages
DHigh-speed CW identification to avoid fading

12. - E2E02

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

SelectAnswer
AFatal Error Correction
BFirst Error Correction
CForward Error Correction
DFinal Error Correction

13. - E3A02

What characterizes libration fading of an EME signal?

SelectAnswer
AThe returning echo is several hertz lower in frequency than the transmitted signal
BA gradual loss of signal as the sun rises
CA fluttery irregular fading
DA slow change in the pitch of the CW signal

14. - E3B07

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

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

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. - E4A10

Which of the following displays multiple digital signal states simultaneously?

SelectAnswer
ALogic analyzer
BBit error rate tester
CNetwork analyzer
DModulation monitor

17. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

SelectAnswer
ATemperature coefficient of the logic
BTime base accuracy
CDecade divider accuracy
DInput attenuator accuracy

18. - E4C11

Why can an attenuator be used to reduce receiver overload on the lower frequency HF bands with little or no impact on signal-to-noise ratio?

SelectAnswer
ASignals are attenuated separately from the noise
BThe attenuator has a low-pass filter to increase the strength of lower frequency signals
CAtmospheric noise is generally greater than internally generated noise even after attenuation
DThe attenuator has a noise filter to suppress interference

19. - E4D08

What causes intermodulation in an electronic circuit?

SelectAnswer
APositive feedback
BToo little gain
CLack of neutralization
DNonlinear circuits or devices

20. - E4E03

Which of the following signals might a receiver noise blanker be able to remove from desired signals?

SelectAnswer
ASignals that appear at one IF but not another
BSignals that have a sharply peaked frequency distribution
CSignals that appear across a wide bandwidth
DSignals that are constant at all IF levels

21. - E5A07

What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

SelectAnswer
AMaximum
BMinimum
CL/R
DR/L

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 unchanged
CIt becomes the reciprocal
DIt is shifted by 90 degrees

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 8
BPoint 7
CPoint 3
DPoint 1

24. - E5D04

Why are short connections used at microwave frequencies?

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

25. - E6A10

In Figure E6-1, what is the schematic symbol for an N-channel dual-gate MOSFET?

SelectAnswer
A4
B5
C2
D6

26. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch?

SelectAnswer
AAbility to dissipate large amounts of power
BExtremely high reverse breakdown voltage
CLow junction capacitance
DReverse bias controls its forward voltage drop

27. - E6C08

In Figure E6-3, what is the schematic symbol for a NAND gate?

SelectAnswer
A3
B2
C1
D4

28. - E6D06

What core material property determines the inductance of an inductor?

SelectAnswer
AResistance
BThermal impedance
CReactivity
DPermeability

29. - E6E07

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

SelectAnswer
AMiniature coax
BMicrostrip
CCircular waveguide
DParallel wire

30. - E6F10

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

SelectAnswer
ACadmium Sulfide
BSelenium
CSilicon
DCopper oxide

31. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

SelectAnswer
AAstable multivibrator
BT flip-flop
CMonostable multivibrator
DJ-K flip-flop

32. - E7B18

What is a characteristic of a grounded-grid amplifier?

SelectAnswer
AHigh power gain
BLow bandwidth
CLow input impedance
DHigh filament voltage

33. - E7C01

How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network's input and output?

SelectAnswer
AA capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between input and output
BTwo inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground
CAn inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output
DTwo capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground

34. - E7D11

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

SelectAnswer
AProvides a stable input impedance over a wide range of source voltage
BPermits a wide range of output voltage settings
CMaintains nearly constant output voltage over a wide range of load current
DMaintains nearly constant output impedance over a wide range of load current

35. - E7E03

What is a frequency discriminator stage in a FM receiver?

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

36. - E7F08

What is the function of decimation?

SelectAnswer
AConverting data to binary code decimal form
BAttenuating the signal
CRemoving unnecessary significant digits
DReducing the effective sample rate by removing samples

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-2.3 volts
B-0.23 volts
C0.23 volts
D2.3 volts

38. - E7H05

How is positive feedback supplied in a Pierce oscillator?

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

39. - E8A06

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

SelectAnswer
A1 to 1
B25 to 1
C2.5 to 1
D100 to 1

40. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

SelectAnswer
A0.167
B60
C0.6
D1.67

41. - E8C10

How may data rate be increased without increasing bandwidth?

SelectAnswer
AUsing forward error correction
BUsing a more efficient digital code
CIt is impossible
DIncreasing analog-to-digital conversion resolution

42. - E8D09

What is considered an acceptable maximum IMD level for an idling PSK signal?

SelectAnswer
A+10 dB
B-20 dB
C+15 dB
D-30 dB

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
A8.15 dB
B6.0 dB
C3.85 dB
D2.79 dB

44. - E9B01

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

SelectAnswer
A50 degrees
B25 degrees
C30 degrees
D75 degrees

45. - E9C09

Which of the following describes a G5RV antenna?

SelectAnswer
AA phased array antenna consisting of multiple loops
BA multi-band trap antenna
CA wide band dipole using shorted coaxial cable for the radiating elements and fed with aÿ4:1 balun
DA multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line

46. - E9D05

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

SelectAnswer
AThe SWR is reduced
BThe frequency response is widened over the whole frequency band
CThe front-to-back ratio decreases
DThe front-to-back ratio increases

47. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

SelectAnswer
ATo provide a rejection notch that prevents the radiation of harmonics
BTo provide DC isolation between the feed line and the antenna
CTo cancel the inductive reactance of the matching network
DTo transform the antenna impedance to a higher value

48. - E9F08

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

SelectAnswer
AFoam dielectric has lower loss per unit of length
BFoam dielectric has lower safe operating voltage limits
CAll these choices are correct
DFoam dielectric has higher velocity factor

49. - E9G10

What do the arcs on a Smith chart represent?

SelectAnswer
APoints with constant resistance
BSWR
CPoints with constant reactance
DFrequency

50. - E9H09

What is a Pennant antenna?

SelectAnswer
AA four-element, high-gain vertical array invented by George Pennant
BA stealth antenna built to look like a flagpole
CA form of rhombic antenna terminated in a variable capacitor to provide frequency diversity
DA small, vertically oriented receiving antenna consisting of a triangular loop terminated in approximately 900 ohms

Figure E5-1

Figure E6-1

Figure E6-3

Figure E7-3

Figure E9-1