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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. - E1B05

What is the National Radio Quiet Zone?

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

3. - E1C07

What is meant by local control?

SelectAnswer
AControlling a repeater using a portable handheld transceiver
BDirect manipulation of the transmitter by a control operator
CControlling a station through a local auxiliary link
DAutomatically manipulating local station controls

4. - E1D05

What class of licensee is authorized to be the control operator of a space station?

SelectAnswer
AOnly Amateur Extra Class
BAny class with appropriate operator privileges
CAll except Technician Class
DOnly General, Advanced or Amateur Extra Class

5. - E1E13

Which of these choices is an acceptable method for monitoring the applicants if a VEC opts to conduct an exam session remotely?

SelectAnswer
AThe exam proctor observes the applicants and reports any violations
BUse a real-time video link and the Internet to connect the exam session to the observing VEs
CHave each applicant sign an affidavit stating that all session rules were followed
DRecord the exam session on video tape for later review by the VE team

6. - E1F07

When may an amateur station send a message to a business?

SelectAnswer
AWhen the total money involved does not exceed $25
BWhen neither the amateur nor his or her employer has a pecuniary interest in the communications
CWhen the control operator is employed by the FCC or another government agency
DWhen transmitting international third-party communications

7. - E2A13

What type of satellite appears to stay in one position in the sky?

SelectAnswer
AGeomagnetic
BGeostationary
CLEO
DHEO

8. - E2B12

How are analog SSTV images typically transmitted on the HF bands?

SelectAnswer
AVarying tone frequencies representing the video are transmitted using PSK
BVarying tone frequencies representing the video are transmitted using single sideband
CVideo is converted to equivalent ASCII representation
DVideo is converted to equivalent Baudot representation

9. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

SelectAnswer
ASend your full call sign and grid square
BSend only the last two letters of your call sign until you make contact
CSend your full call sign once or twice
DSend the call sign of the DX station three times, the words "this is", then your call sign three times

10. - E2D03

Which of the following digital modes is especially useful for EME communications?

SelectAnswer
AOlivia
BJT65
CFSK441
DPACTOR III

11. - E2E05

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

SelectAnswer
AWinlink
BMFSK
CRTTY
DPSK31

12. - E3A17

What is meant by circularly polarized electromagnetic waves?

SelectAnswer
AWaves with a rotating electric field
BWaves produced by a loop antenna
CWaves with an electric field bent into a circular shape
DWaves that circle the Earth

13. - E3B01

What is transequatorial propagation?

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

14. - E3C11

What does VOACAP software model?

SelectAnswer
AHF propagation
BAC current and impedance
CVHF radio propagation
DAC voltage and impedance

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

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

16. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

SelectAnswer
A100 watts
B25 watts
C75 watts
D125 watts

17. - E4C02

Which of the following portions of a receiver can be effective in eliminating image signal interference?

SelectAnswer
AA front-end filter or pre-selector
BA notch filter
CA properly adjusted product detector
DA narrow IF filter

18. - E4D12

What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?

SelectAnswer
AQuieting
BDesensitization
CSquelch gain rollback
DCross-modulation interference

19. - E4E08

What type of signal is picked up by electrical wiring near a radio antenna?

SelectAnswer
AA common-mode signal at the frequency of the radio transmitter
BA differential-mode signal at the AC power line frequency
CHarmonics of the AC power line frequency
DAn electrical-sparking signal

20. - E5A02

What is resonance in an electrical circuit?

SelectAnswer
AThe frequency at which the reactive impedance equals the resistive impedance
BThe lowest frequency that will pass current
CThe highest frequency that will pass current
DThe frequency at which the capacitive reactance equals the inductive reactance

21. - E5B05

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

SelectAnswer
AThe magnitude of the susceptance is the reciprocal of the magnitude of the reactance
BThe sign is reversed
CIt is shifted by 90 degrees
DIt is unchanged

22. - E5C13

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

SelectAnswer
ARectangular coordinates
BMaidenhead grid
CFaraday grid
DElliptical coordinates

23. - E5D03

What is microstrip?

SelectAnswer
AMiniature coax used for low power applications
BShort lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
CLightweight transmission line made of common zip cord
DPrecision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies

24. - E6A15

Which semiconductor material contains excess holes in the outer shell of electrons?

SelectAnswer
AP-type
BSuperconductor-type
CN-type
DBipolar-type

25. - E6B07

What is the failure mechanism when a junction diode fails due to excessive current?

SelectAnswer
AExcessive inverse voltage
BCharge carrier depletion
CInsufficient forward voltage
DExcessive junction temperature

26. - E6C09

What is a Programmable Logic Device (PLD)?

SelectAnswer
AAn algorithm for simulating logic functions during circuit design
BA device to control industrial equipment
CA programmable collection of logic gates and circuits in a single integrated circuit
DProgrammable equipment used for testing digital logic integrated circuits

27. - E6D11

How many turns will be required to produce a 1-mH inductor using a core that has an inductance index (A L) value of 523 millihenrys/1000 turns?

SelectAnswer
A43 turns
B229 turns
C4 turns
D2 turns

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

SelectAnswer
AMicrostrip construction
BPoint-to-point construction
CWave-soldering construction
DGround-plane construction

29. - E6F05

Which describes an optical shaft encoder?

SelectAnswer
AA device which detects rotation of a control by interrupting a light source with a patterned wheel
BA digital encryption device often used to encrypt spacecraft control signals
CA device for generating RTTY signals by means of a rotating light source
DA device which measures the strength of a beam of light using analog to digital conversion

30. - E7A09

What logical operation is performed by an exclusive NOR gate?

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

31. - E7B02

What is a Class D amplifier?

SelectAnswer
AA low power amplifier that uses a differential amplifier for improved linearity
BA type of amplifier that uses switching technology to achieve high efficiency
CAn amplifier that uses drift-mode FETs for high efficiency
DA frequency doubling amplifier

32. - E7C13

What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?

SelectAnswer
AL-networks cannot perform impedance transformation
BPi-networks are designed for balanced input and output
CPi-networks have fewer components
DThe Q of Pi-networks can be varied depending on the component values chosen

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

34. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

SelectAnswer
AA heterodyne suppressor
BA pre-emphasis network
CAn audio prescaler
DA de-emphasis network

35. - E7F11

What sets the minimum detectable signal level for an SDR in the absence of atmospheric or thermal noise?

SelectAnswer
AData storage transfer rate
BMissing codes and jitter
CSample clock phase noise
DReference voltage level and sample width in bits

36. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 3300 ohms and RF is 47 kilohms?

SelectAnswer
A28
B0.07
C14
D7

37. - E7H15

Which of these functions can be performed by a phase-locked loop?

SelectAnswer
APhotovoltaic conversion, optical coupling
BWide-band AF and RF power amplification
CFrequency synthesis, FM demodulation
DComparison of two digital input signals, digital pulse counter

38. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

SelectAnswer
AVery high speed allows digitizing high frequencies
BImmunity to out of sequence coding reduces spurious responses
CVery low power consumption decreases frequency drift
DAll of these choices are correct

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

SelectAnswer
AA frequency modulation technique which uses non-harmonically related frequencies
BA bandwidth compression technique using Fourier transforms
CA digital mode for narrow band, slow speed transmissions
DA digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference

40. - E8C04

What technique is used to minimize the bandwidth requirements of a PSK31 signal?

SelectAnswer
AZero-sum character encoding
BUse of sinusoidal data pulses
CReed-Solomon character encoding
DUse of trapezoidal data pulses

41. - E8D01

Why are received spread spectrum signals resistant to interference?

SelectAnswer
ASignals not using the spread spectrum algorithm are suppressed in the receiver
BThe high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
CThe receiver is always equipped with a digital blanker
DIf interference is detected by the receiver it will signal the transmitter to change frequencies

42. - E9A11

Which of the following factors determines ground losses for a ground-mounted vertical antenna operating in the 3 MHz to 30 MHz range?

SelectAnswer
ASoil conductivity
BThe standing wave ratio
CDistance from the transmitter
DTake-off angle

43. - E9B09

What type of computer program technique is commonly used for modeling antennas?

SelectAnswer
AGraphical analysis
BCalculus differentiation with respect to physical properties
CMutual impedance analysis
DMethod of Moments

44. - E9C06

What is the effect of a terminating resistor on a rhombic antenna?

SelectAnswer
AIt reflects the standing waves on the antenna elements back to the transmitter
BIt changes the radiation pattern from horizontal to vertical polarization
CIt changes the radiation pattern from bidirectional to unidirectional
DIt decreases the ground loss

45. - E9D09

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

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

46. - E9E09

Which of these matching systems is an effective method of connecting a 50 ohm coaxial cable feed line to a grounded tower so it can be used as a vertical antenna?

SelectAnswer
ADouble-bazooka match
BHairpin match
CGamma match
DAll of these choices are correct

47. - E9F08

What is the term for the ratio of the actual speed at which a signal travels through a transmission line to the speed of light in a vacuum?

SelectAnswer
AVelocity factor
BCharacteristic impedance
CStanding wave ratio
DSurge impedance

48. - E9G05

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

SelectAnswer
AFree space radiation directivity chart
BElevation angle radiation pattern chart
CSmith chart
DAzimuth angle radiation pattern chart

49. - E9H07

Why is it advisable to use an RF attenuator on a receiver being used for direction finding?

SelectAnswer
AIt compensates for the effects of an isotropic antenna, thereby improving directivity
BIt prevents receiver overload which could make it difficult to determine peaks or nulls
CIt narrows the bandwidth of the received signal to improve signal to noise ratio
DIt reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity

50. - E0A08

What does SAR measure?

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

Figure E7-4

Figure E9-3