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

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1. - 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

2. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

SelectAnswer
AAll amateur service frequencies authorized to the control operator
BSpecific local government channels
CMilitary Auxiliary Radio System (MARS) channels
DSpecific segments in the amateur service MF, HF, VHF and UHF bands

3. - E1C10

What types of amateur stations may automatically retransmit the radio signals of other amateur stations?

SelectAnswer
AOnly beacon, repeater or space stations
BOnly earth stations, repeater stations or model craft
COnly auxiliary, beacon or space stations
DOnly auxiliary, repeater or space stations

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

SelectAnswer
AAll HF bands
BOnly the 40 m, 20 m, 17 m, 15 m and 10 m bands
COnly the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands
DOnly the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands

5. - E1E08

To which of the following examinees may a VE not administer an examination?

SelectAnswer
ARelatives of the VE as listed in the FCC rules
BAll of these choices are correct
CEmployees of the VE
DFriends of the VE

6. - E1F02

What privileges are authorized in the U.S. to persons holding an amateur service license granted by the Government of Canada?

SelectAnswer
AAll privileges of the Extra Class license
BThe operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Extra Class privileges
CFull privileges, up to and including those of the Extra Class License, on the 80, 40, 20, 15, and 10 meter bands
DNone, they must obtain a U.S. license

7. - E2A11

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

SelectAnswer
AA linearly polarized antenna
BAn isotropic antenna
CA log-periodic dipole array
DA circularly 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
A3 KHz
B20 KHz
C10 KHz
D15 KHz

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

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

10. - E2D14

What is one advantage of using JT65 coding?

SelectAnswer
AEasily copied by ear if necessary
BUses only a 65 Hz bandwidth
CThe ability to decode signals which have a very low signal to noise ratio
DPermits fast-scan TV transmissions over narrow bandwidth

11. - E2E12

Which type of control is used by stations using the Automatic Link Enable (ALE) protocol?

SelectAnswer
AAutomatic
BLocal
CALE can use any type of control
DRemote

12. - E3A16

Which of the following best describes electromagnetic waves traveling in free space?

SelectAnswer
AElectric and magnetic fields become aligned as they travel
BChanging electric and magnetic fields propagate the energy
CThe energy propagates through a medium with a high refractive index
DThe waves are reflected by the ionosphere and return to their source

13. - E3B01

What is transequatorial propagation?

SelectAnswer
APropagation between any two points located on the magnetic equator
BPropagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
CPropagation between two continents by way of ducts along the magnetic equator
DPropagation between two stations at the same latitude

14. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

SelectAnswer
ASporadic-E
BTransequatorial propagation
CNVIS
DPolar paths

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

SelectAnswer
AA square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
BA frequency standard is displayed and the probe is adjusted until the deflection time is accurate
CA high frequency sine wave is displayed and the probe is adjusted for maximum amplitude
DA DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate

16. - E4B14

What happens if a dip meter is too tightly coupled to a tuned circuit being checked?

SelectAnswer
AHarmonics are generated
BIntermodulation distortion occurs
CA less accurate reading results
DCross modulation occurs

17. - E4C08

An SDR receiver is overloaded when input signals exceed what level?

SelectAnswer
AOne-half the maximum sample rate
BOne-half the maximum sampling buffer size
CThe maximum count value of the analog-to-digital converter
DThe reference voltage of the analog-to-digital converter

18. - E4D09

What is the purpose of the preselector in a communications receiver?

SelectAnswer
ATo increase rejection of unwanted signals
BTo store often-used frequencies
CTo allow selection of the optimum RF amplifier device
DTo provide a range of AGC time constants

19. - E4E09

What undesirable effect can occur when using an IF noise blanker?

SelectAnswer
AReceived audio in the speech range might have an echo effect
BNearby signals may appear to be excessively wide even if they meet emission standards
CFM signals can no longer be demodulated
DThe audio frequency bandwidth of the received signal might be compressed

20. - E5A17

What is the result of increasing the Q of an impedance-matching circuit?

SelectAnswer
AMatching bandwidth is increased
BIt has no effect on impedance matching
CMatching range is increased
DMatching bandwidth is decreased

21. - E5B01

What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the applied voltage?

SelectAnswer
AOne exponential period
BOne time constant
CAn exponential rate of one
DA time factor of one

22. - E5C10

When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?

SelectAnswer
AThe difference between the resistive and reactive components
BThe sum of the reactive and resistive components
CResistive component
DReactive component

23. - E5D14

What is reactive power?

SelectAnswer
APower consumed in wire resistance in an inductor
BWattless, nonproductive power
CPower lost because of capacitor leakage
DPower consumed in circuit Q

24. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

SelectAnswer
AAlpha rejection frequency
BBeta cutoff frequency
CAlpha cutoff frequency
DCorner frequency

25. - E6B04

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

SelectAnswer
AZener diode
BVaractor diode
CSilicon-controlled rectifier
DTunnel diode

26. - E6C12

What is BiCMOS logic?

SelectAnswer
AA FET logic family based on bimetallic semiconductors
BA logic device with two CMOS circuits per package
CA logic family based on bismuth CMOS devices
DAn integrated circuit logic family using both bipolar and CMOS transistors

27. - E6D08

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

SelectAnswer
APowdered-iron cores generally require fewer turns to produce a given inductance
BPowdered-iron cores generally maintain their characteristics at higher currents
CPowdered-iron cores generally have greater initial permeability
DPowdered-iron cores use smaller diameter wire for the same inductance

28. - E6E12

Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?

SelectAnswer
ABetter dissipation of heat
BTo provide a low-pass frequency response
CHigh-voltage insulating ability
DEnhanced sensitivity to light

29. - E6F13

What is a liquid crystal display (LCD)?

SelectAnswer
AA display that uses a glowing liquid to remain brightly lit in dim light
BA frequency-determining unit for a transmitter or receiver
CA display utilizing a crystalline liquid and polarizing filters which becomes opaque when voltage is applied
DA modern replacement for a quartz crystal oscillator which displays its fundamental frequency

30. - E7A11

What type of logic defines "1" as a high voltage?

SelectAnswer
AReverse Logic
BAssertive Logic
CNegative logic
DPositive Logic

31. - E7B17

Why are odd-order rather than even-order intermodulation distortion products of concern in linear power amplifiers?

SelectAnswer
ABecause they maintain the sidebands, thus causing multiple duplicate signals
BBecause they are relatively far in frequency from the desired signal
CBecause they are relatively close in frequency to the desired signal
DBecause they invert the sidebands causing distortion

32. - E7C06

What are the distinguishing features of an elliptical filter?

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

33. - E7D16

When several electrolytic filter capacitors are connected in series to increase the operating voltage of a power supply filter circuit, why should resistors be connected across each capacitor?

SelectAnswer
AAll of these choices are correct
BTo equalize, as much as possible, the voltage drop across each capacitor
CTo provide a safety bleeder to discharge the capacitors when the supply is off
DTo provide a minimum load current to reduce voltage excursions at light loads

34. - E7E04

What is one way a single-sideband phone signal can be generated?

SelectAnswer
ABy using a reactance modulator followed by a mixer
BBy using a loop modulator followed by a mixer
CBy using a balanced modulator followed by a filter
DBy driving a product detector with a DSB signal

35. - E7F16

How might the sampling rate of an existing digital signal be adjusted by a factor of 3/4?

SelectAnswer
AAdd 3 to each input value and subtract 4 from each output value
BInterpolate by a factor of three, then decimate by a factor of four
CMultiply each sample value by a factor of 3/4
DChange the gain by a factor of 3/4

36. - E7G01

What is the typical output impedance of an integrated circuit op-amp?

SelectAnswer
A1000 ohms
BVery low
C100 ohms
DVery high

37. - 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 diode-switching matrix synthesizer
CA hybrid synthesizer
DA phase locked loop synthesizer

38. - E8A05

What would be the most accurate way of measuring the RMS voltage of a complex waveform?

SelectAnswer
ABy using a grid dip meter
BBy measuring the voltage with a D'Arsonval meter
CBy using an absorption wave meter
DBy measuring the heating effect in a known resistor

39. - 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
A2000
B1/3
C3
D6000

40. - E8C03

When performing phase shift keying, why is it advantageous to shift phase precisely at the zero crossing of the RF carrier?

SelectAnswer
AAll of these choices are correct
BIt improves carrier suppression
CThis results in the least possible transmitted bandwidth for the particular mode
DIt is easier to demodulate with a conventional, non-synchronous detector

41. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

SelectAnswer
ALimits data speed
BThe generation of key clicks
CMore difficult to copy
DThe generation of RF harmonics

42. - E9A04

Which of the following factors may affect the feed point impedance of an antenna?

SelectAnswer
ASunspot activity and time of day
BAntenna height, conductor length/diameter ratio and location of nearby conductive objects
CTransmission-line length
DThe settings of an antenna tuner at the transmitter

43. - E9B06

What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

SelectAnswer
A25 degrees
B45 degrees
C75 degrees
D7.5 degrees

44. - E9C15

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with its height above ground?

SelectAnswer
AThe horizontal beam width increases with height
BThe main lobe takeoff angle decreases with increasing height
CThe horizontal beam width decreases with height
DThe main lobe takeoff angle increases with increasing height

45. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

SelectAnswer
ATo lower the losses
BTo cancel capacitive reactance
CTo increase the SWR bandwidth
DTo lower the Q

46. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

SelectAnswer
AThe gamma match
BThe epsilon match
CThe delta match
DThe stub match

47. - E9F16

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
CFoam dielectric has higher velocity factor
DAll of these choices are correct

48. - E9G05

What type of chart is shown in Figure E9-3?

SelectAnswer
AElevation angle radiation pattern chart
BFree space radiation directivity chart
CAzimuth angle radiation pattern chart
DSmith chart

49. - E9H08

What is the function of a sense antenna?

SelectAnswer
AIt increases the sensitivity of a DF antenna array
BIt provides diversity reception that cancels multipath signals
CIt allows DF antennas to receive signals at different vertical angles
DIt modifies the pattern of a DF antenna array to provide a null in one direction

50. - 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
AEach transmitter operating with a duty-cycle greater than 50 percent
BEach transmitter that produces 5 percent or more of its MPE limit at accessible locations
COnly commercial transmitters
DOnly the most powerful transmitter

Figure E9-2

Figure E9-3