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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. - E1B02

Which of the following factors might cause the physical location of an amateur station apparatus or antenna structure to be restricted?

SelectAnswer
AThe location is of geographical or horticultural importance
BThe location is in an ITU Zone designated for coordination with one or more foreign governments
CThe location is near an area of political conflict
DThe location is of environmental importance or significant in American history, architecture, or culture

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

4. - E1D09

Which UHF amateur service bands have frequencies available for a space station?

SelectAnswer
A70 cm only
B70 cm and 13 cm
C70 cm and 33 cm
D33 cm and 13 cm

5. - E1E01

What is the minimum number of qualified VEs required to administer an Element 4 amateur operator license examination?

SelectAnswer
A2
B4
C3
D5

6. - E1F07

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

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

7. - E2A07

Which of the following types of signals can be relayed through a linear transponder?

SelectAnswer
ASSB and SSTV
BAll of these choices are correct
CPSK and Packet
DFM and CW

8. - E2B08

Which of the following is a common method of transmitting accompanying audio with amateur fast-scan television?

SelectAnswer
AFrequency-modulated sub-carrier
BAll of these choices are correct
CA separate VHF or UHF audio link
DFrequency modulation of the video carrier

9. - E2C05

What is the function of a DX QSL Manager?

SelectAnswer
ATo allocate frequencies for DXpeditions
BTo handle the receiving and sending of confirmation cards for a DX station
CTo run a net to allow many stations to contact a rare DX station
DTo relay calls to and from a DX station

10. - E2D11

Which of the following data are used by the APRS network to communicate your location?

SelectAnswer
APolar coordinates
BRadio direction finding spectrum analysis
CTime and frequency
DLatitude and longitude

11. - E2E12

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

SelectAnswer
AAutomatic
BRemote
CALE can use any type of control
DLocal

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. - E3B03

What is the best time of day for transequatorial propagation?

SelectAnswer
ANoon
BMorning
CLate at night
DAfternoon or early evening

14. - E3C10

What does the 304A solar parameter measure?

SelectAnswer
AUV emissions at 304 angstroms, correlated to solar flux index
BThe solar emission at 304 GHz, correlated to X-Ray flare levels
CThe solar wind velocity at 304 degrees from the solar equator, correlated to solar activity
DThe ratio of X-Ray flux to radio flux, correlated to sunspot number

15. - E4A03

Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?

SelectAnswer
AA spectrum analyzer
BA logic analyzer
CA wattmeter
DA time-domain reflectometer

16. - E4B04

If a frequency counter with a specified accuracy of +/- 0.1 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

SelectAnswer
A0.1 MHz
B1.4652 kHz
C14.652 Hz
D1.4652 Hz

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 narrow IF filter
CA notch filter
DA properly adjusted product detector

18. - E4D05

What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

SelectAnswer
A146.10 MHz and 147.30 MHz
B173.35 MHz and 139.40 MHz
C146.88 MHz and 146.34 MHz
D146.34 MHz and 146.61 MHz

19. - E4E06

What is a major cause of atmospheric static?

SelectAnswer
AMeteor showers
BSolar radio frequency emissions
CGeomagnetic storms
DThunderstorms

20. - E5A07

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

SelectAnswer
AL/R
BMaximum
CMinimum
DR/L

21. - E5B11

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?

SelectAnswer
A14 degrees with the voltage leading the current
B76 degrees with the voltage lagging the current
C14 degrees with the voltage lagging the current
D76 degrees with the voltage leading the current

22. - E5C11

What do the two numbers that are used to define a point on a graph using rectangular coordinates represent?

SelectAnswer
AThe magnitude and phase of the point
BThe coordinate values along the horizontal and vertical axes
CThe sine and cosine values
DThe tangent and cotangent values

23. - E5D08

What type of energy is stored in an electromagnetic or electrostatic field?

SelectAnswer
AKinetic energy
BThermodynamic energy
CPotential energy
DElectromechanical energy

24. - E6A09

What is a depletion-mode FET?

SelectAnswer
AAny FET for which holes are the majority carriers
BAny FET without a channel
CAn FET that exhibits a current flow between source and drain when no gate voltage is applied
DAn FET that has no current flow between source and drain when no gate voltage is applied

25. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

SelectAnswer
AControlled reverse avalanche voltage
BMuch higher reverse voltage breakdown
CEnhanced carrier retention time
DLess forward voltage drop

26. - E6C08

In Figure E6-5, what is the schematic symbol for a NAND gate?

SelectAnswer
A3
B4
C2
D1

27. - E6D06

What core material property determines the inductance of a toroidal inductor?

SelectAnswer
AResistance
BPermeability
CThermal impedance
DReactivity

28. - E6E05

Which of the following noise figure values is typical of a low-noise UHF preamplifier?

SelectAnswer
A44 dBm
B2 dB
C-20 dBm
D-10 dB

29. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

SelectAnswer
AIt stays the same
BIt decreases
CIt becomes unstable
DIt increases

30. - E7A05

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

SelectAnswer
AAstable multivibrator
BMonostable multivibrator
CT flip-flop
DJ-K flip-flop

31. - E7B07

Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?

SelectAnswer
ASignal inversion
BReduced intermodulation products
CIncreased overall intelligibility
DSignal distortion and excessive bandwidth

32. - E7C12

Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50 ohm unbalanced output?

SelectAnswer
AA Pi-network with an additional series inductor on the output
BA Phase Inverter Load network
CA matching network in which all components are isolated from ground
DA network with only three discrete parts

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

34. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

SelectAnswer
AMixer blanking occurs
BAutomatic limiting occurs
CSpurious mixer products are generated
DA beat frequency is generated

35. - E7F04

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

SelectAnswer
AEmulation of quartz crystal filter characteristics
BMixing products are converted to voltages and subtracted by adder circuits
CCombine signals with a quadrature phase relationship
DA frequency synthesizer removes the unwanted sidebands

36. - E7G05

How can unwanted ringing and audio instability be prevented in a multi-section op-amp RC audio filter circuit?

SelectAnswer
ARestrict both gain and Q
BRestrict Q but increase gain
CRestrict gain but increase Q
DIncrease both gain and Q

37. - E7H07

How can an oscillator's microphonic responses be reduced?

SelectAnswer
AMechanically isolating the oscillator circuitry from its enclosure
BUsing the oscillator only for CW and digital signals
CUse of NP0 capacitors
DEliminating noise on the oscillator's power supply

38. - E8A10

What is the purpose of a low pass filter used in conjunction with a digital-to-analog converter?

SelectAnswer
AAll of these choices are correct
BRemove harmonics from the output caused by the discrete analog levels generated
CImprove accuracy by removing out of sequence codes from the input
DLower the input bandwidth to increase the effective resolution

39. - E8B11

What is digital time division multiplexing?

SelectAnswer
ATwo or more data streams are assigned to discrete sub-carriers on an FM transmitter
BTwo or more data streams share the same channel by transmitting time of transmission as the sub-carrier
CTwo or more signals are quadrature modulated to increase bandwidth efficiency
DTwo or more signals are arranged to share discrete time slots of a data transmission

40. - E8C07

What is the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

SelectAnswer
A15.36 kHz
B9.6 kHz
C5.76 kHz
D4.8 kHz

41. - E8D03

How does the spread spectrum technique of frequency hopping work?

SelectAnswer
AA pseudo-random binary bit stream is used to shift the phase of an RF carrier very rapidly in a particular sequence
BIf interference is detected by the receiver it will signal the transmitter to change frequencies
CIf interference is detected by the receiver it will signal the transmitter to wait until the frequency is clear
DThe frequency of the transmitted signal is changed very rapidly according to a particular sequence also used by the receiving station

42. - E9A04

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

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

43. - E9B14

What type of information can be obtained by submitting the details of a proposed new antenna to a modeling program?

SelectAnswer
AAll of these choices are correct
BPolar plots of the far field elevation and azimuth patterns
CSWR vs frequency charts
DAntenna gain

44. - E9C01

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed 180 degrees out of phase?

SelectAnswer
AA figure-8 broadside to the axis of the array
BOmni-directional
CA figure-8 oriented along the axis of the array
DCardioid

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

SelectAnswer
AHigher losses
BLower Q
CImproved radiation efficiency
DGreater structural strength

46. - E9E01

What system matches a higher impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

SelectAnswer
AThe delta matching system
BThe stub matching system
CThe gamma matching system
DThe omega matching system

47. - E9F01

What is the velocity factor of a transmission line?

SelectAnswer
AThe ratio of the characteristic impedance of the line to the terminating impedance
BThe index of shielding for coaxial cable
CThe velocity of the wave in the transmission line divided by the velocity of light in a vacuum
DThe velocity of the wave in the transmission line multiplied by the velocity of light in a vacuum

48. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

SelectAnswer
AVoltage and impedance
BResistance and reactance
CResistance and voltage
DReactance and voltage

49. - E9H06

What is the triangulation method of direction finding?

SelectAnswer
AAntenna headings from several different receiving locations are used to locate the signal source
BThe geometric angles of sky waves from the source are used to determine its position
CA fixed receiving station uses three different antennas to plot the location of the signal source
DA fixed receiving station plots three headings to the signal source

50. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

SelectAnswer
AIngestion of ozone gas from the cooling system
BHearing loss caused by high voltage corona discharge
CBlood clotting from the intense magnetic field
DLocalized heating of the body from RF exposure in excess of the MPE limits

Figure E6-5