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

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1. - E1A13

Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?

SelectAnswer
AAny person named in an amateur station license grant or a person holding an unrestricted Radiotelephone Operator Permit
BAny person holding an FCC issued amateur license or who is authorized for alien reciprocal operation
COnly a person with an FCC Marine Radio
DOnly a person named in an amateur station license grant

2. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

SelectAnswer
ANo special rules apply if your antenna structure will be less than 300 feet in height
BYou must file an Environmental Impact Statement with the EPA before construction begins
CYou may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules
DYou must obtain a construction permit from the airport zoning authority

3. - E1C04

What is meant by IARP?

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

4. - E1D02

What is the amateur satellite service?

SelectAnswer
AA radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
BA radio communications service using amateur radio stations on satellites
CA radio communications service using stations on Earth satellites for public service broadcast
DA spacecraft launching service for amateur-built satellites

5. - E1E04

Which of the following best describes the Volunteer Examiner accreditation process?

SelectAnswer
AThe prospective VE obtains accreditation from the FCC
BThe procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner
CEach General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
DThe amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

SelectAnswer
AThe transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions
BA station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
CAll of these choices are correct
DThe transmission must not be used to obscure the meaning of any communication

7. - E2A06

On what band would a satellite receive signals if it were operating in mode U/V?

SelectAnswer
A144 MHz - 146 MHz
B435 MHz - 438 MHz
C50.0 MHz - 50.2 MHz
D29.5 MHz - 29.7 MHz

8. - E2B02

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

SelectAnswer
A60
B525
C1080
D30

9. - E2C08

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

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

10. - E2D01

Which of the following digital modes is especially designed for use for meteor scatter signals?

SelectAnswer
AWSPR
BFSK441
CHellschreiber
DAPRS

11. - E2E05

Which type of digital mode does not support keyboard-to-keyboard operation?

SelectAnswer
ARTTY
BMFSK
CWinlink
DPSK31

12. - E3A07

Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?

SelectAnswer
AMountain ranges
BForests
CUrban areas
DBodies of water

13. - E3B04

What is meant by the terms extraordinary and ordinary waves?

SelectAnswer
AIndependent waves created in the ionosphere that are elliptically polarized
BLong path and short path waves
CExtraordinary waves describe rare long skip propagation compared to ordinary waves which travel shorter distances
DRefracted rays and reflected waves

14. - E3C09

How does the intensity of an X3 flare compare to that of an X2 flare?

SelectAnswer
A10 percent greater
BTwice as great
C50 percent greater
DFour times as great

15. - E4A01

Which of the following parameter determines the bandwidth of a digital or computer-based oscilloscope?

SelectAnswer
AInput impedance
BSample resolution
CSampling rate
DInput capacitance

16. - E4B13

Which S parameter is equivalent to forward gain?

SelectAnswer
AS21
BS11
CS12
DS22

17. - E4C10

Which of the following is a desirable amount of selectivity for an amateur RTTY HF receiver?

SelectAnswer
A300 Hz
B2400 Hz
C6000 Hz
D100 Hz

18. - E4D06

What is the term for unwanted signals generated by the mixing of two or more signals?

SelectAnswer
AIntermodulation interference
BNeutralization
CAdjacent channel interference
DAmplifier desensitization

19. - E4E12

What is one disadvantage of using some types of automatic DSP notch-filters when attempting to copy CW signals?

SelectAnswer
AA DSP filter can remove the desired signal at the same time as it removes interfering signals
BRinging in the DSP filter will completely remove the spaces between the CW characters
CReceived CW signals will appear to be modulated at the DSP clock frequency
DAny nearby signal passing through the DSP system will overwhelm the desired signal

20. - E5A08

What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?

SelectAnswer
AThe voltage and current are 180 degrees out of phase
BThe current leads the voltage by 90 degrees
CThe voltage and current are in phase
DThe voltage leads the current by 90 degrees

21. - E5B06

What is susceptance?

SelectAnswer
AThe ratio of magnetic field to electric field
BA measure of the efficiency of a transformer
CThe magnetic impedance of a circuit
DThe inverse of reactance

22. - E5C09

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

SelectAnswer
AThe difference between the resistive and reactive components
BResistive component
CReactive component
DThe sum of the reactive and resistive components

23. - E5D14

What is reactive power?

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

24. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

SelectAnswer
AInsulator impurity
BN-type impurity
CDonor impurity
DAcceptor impurity

25. - E6B04

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

SelectAnswer
AZener diode
BTunnel diode
CVaractor diode
DSilicon-controlled rectifier

26. - E6C01

What is the function of hysteresis in a comparator?

SelectAnswer
ATo allow the comparator to be used with AC input signal
BTo increase the sensitivity
CTo prevent input noise from causing unstable output signals
DTo cause the output to change states continually

27. - E6D03

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

SelectAnswer
AIncreased conductivity in the presence of light
BMechanical deformation of material by the application of a magnetic field
CMechanical deformation of material by the application of a voltage
DGeneration of electrical energy in the presence of light

28. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

SelectAnswer
ASilicon dioxide
BGallium nitride
CSilicon
DSilicon nitride

29. - E6F06

Which of these materials is affected the most by photoconductivity?

SelectAnswer
AA heavy metal
BAn ordinary metal
CA crystalline semiconductor
DA liquid semiconductor

30. - E7A07

What logical operation does a NAND gate perform?

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

31. - E7B08

How can an RF power amplifier be neutralized?

SelectAnswer
ABy increasing the driving power
BBy reducing the driving power
CBy feeding a 180-degree out-of-phase portion of the output back to the input
DBy feeding an in-phase component of the output back to the input

32. - E7C03

What advantage does a Pi-L-network have over a regular Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

SelectAnswer
AGreater harmonic suppression
BLower losses
CGreater transformation range
DHigher efficiency

33. - E7D14

What is one purpose of a "bleeder" resistor in a conventional unregulated power supply?

SelectAnswer
ATo balance the low-voltage filament windings
BTo improve output voltage regulation
CTo cut down on waste heat generated by the power supply
DTo boost the amount of output current

34. - E7E02

What is the function of a reactance modulator?

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

35. - E7F08

What is the function of decimation with regard to digital filters?

SelectAnswer
ARemoving unnecessary significant digits
BAttenuating the signal
CReducing the effective sample rate by removing samples
DConverting data to binary code decimal form

36. - E7G03

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

SelectAnswer
AVery high
BVery low
C100 ohms
D1000 ohms

37. - E7H03

How is positive feedback supplied in a Hartley oscillator?

SelectAnswer
AThrough a tapped coil
BThrough a capacitive divider
CThrough link coupling
DThrough a neutralizing capacitor

38. - E8A12

What is an advantage of using digital signals instead of analog signals to convey the same information?

SelectAnswer
ADigital signals can be regenerated multiple times without error
BAll of these choices are correct
CDigital signals always occupy a narrower bandwidth
DLess complex circuitry is required for digital signal generation and detection

39. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

SelectAnswer
AHigh speed digital modes
BExtremely low-power contacts
CEME
DOFDM signals are not allowed on amateur bands

40. - E8C06

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

SelectAnswer
A0.5 kHz
B0.3 kHz
C1.0 kHz
D0.1 Hz

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

SelectAnswer
AExcessive transmit audio levels
BExcessive numbers of retries
CGround loops
DBit errors in the modem

42. - E9A04

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

SelectAnswer
ATransmission-line length
BThe settings of an antenna tuner at the transmitter
CSunspot activity and time of day
DAntenna height, conductor length/diameter ratio and location of nearby conductive objects

43. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the 3 dB beam-width?

SelectAnswer
A50 degrees
B30 degrees
C25 degrees
D75 degrees

44. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

SelectAnswer
ACardioid
BOmni-directional
CA Figure-8 end-fire along the axis of the array
DA Figure-8 broadside to the axis of the array

45. - E9D10

What happens to feed point impedance at the base of a fixed length HF mobile antenna as the frequency of operation is lowered?

SelectAnswer
AThe radiation resistance decreases and the capacitive reactance increases
BThe radiation resistance decreases and the capacitive reactance decreases
CThe radiation resistance increases and the capacitive reactance increases
DThe radiation resistance increases and the capacitive reactance decreases

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 stub match
CThe delta match
DThe epsilon match

47. - E9F14

What impedance does a 1/2 wavelength transmission line present to a generator when the line is shorted at the far end?

SelectAnswer
AVery high impedance
BThe same as the characteristic impedance of the line
CThe same as the output impedance of the generator
DVery low impedance

48. - E9G06

On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

SelectAnswer
APrime axis
BImpedance axis
CReactance axis
DPolar axis

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

SelectAnswer
AIt is electro statically balanced against ground, giving better nulls
BIt eliminates tracking errors caused by strong out-of-band signals
CIt automatically cancels ignition noise in mobile installations
DIt allows stations to communicate without giving away their position

50. - E0A07

How may dangerous levels of carbon monoxide from an emergency generator be detected?

SelectAnswer
ABy the yellowish appearance of the gas
BAny ordinary smoke detector can be used
CBy the odor
DOnly with a carbon monoxide detector

Figure E9-1

Figure E9-3