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

2. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historical Places?

SelectAnswer
AA proposal must be submitted to the National Park Service
BAn Environmental Assessment must be submitted to the FCC
CA form FSD-15 must be submitted to the Department of the Interior
DA letter of intent must be filed with the National Audubon Society

3. - E1C07

What is meant by local control?

SelectAnswer
AAutomatically manipulating local station controls
BControlling a repeater using a portable handheld transceiver
CDirect manipulation of the transmitter by a control operator
DControlling a station through a local auxiliary link

4. - E1D04

What is an Earth station in the amateur satellite service?

SelectAnswer
AAn amateur station that transmits telemetry consisting of measurement of upper atmosphere
BAny amateur station on the surface of the Earth
CAn amateur station that is not able to communicate using amateur satellites
DAn amateur station within 50 km of the Earth's surface intended for communications with amateur stations by means of objects in space

5. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

SelectAnswer
AAll of these choices are correct
BA fine of up to $1000 per occurrence
CA sentence of up to one year in prison
DRevocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant

6. - E1F02

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

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

7. - E2A03

What is the orbital period of an Earth satellite?

SelectAnswer
AThe point of maximum height of a satellite's orbit
BThe point of minimum height of a satellite's orbit
CThe time it takes for a satellite to travel from perigee to apogee
DThe time it takes for a satellite to complete one revolution around the Earth

8. - E2B02

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

SelectAnswer
A30
B1080
C525
D60

9. - E2C08

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

SelectAnswer
AContacts between a U.S. station and a non-U.S. station
BRepeater contacts between U.S. club members
CContacts using tactical call signs
DSpecial event contacts between stations in the U.S.

10. - E2D14

What is one advantage of using JT65 coding?

SelectAnswer
AUses only a 65 Hz bandwidth
BPermits fast-scan TV transmissions over narrow bandwidth
CEasily copied by ear if necessary
DThe ability to decode signals which have a very low signal to noise ratio

11. - E2E01

Which type of modulation is common for data emissions below 30 MHz?

SelectAnswer
APulse modulation
BSpread spectrum
CDTMF tones modulating an FM signal
DFSK

12. - E3A07

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

SelectAnswer
ABodies of water
BMountain ranges
CUrban areas
DForests

13. - E3B04

What is meant by the terms extraordinary and ordinary waves?

SelectAnswer
ARefracted rays and reflected waves
BIndependent waves created in the ionosphere that are elliptically polarized
CLong path and short path waves
DExtraordinary waves describe rare long skip propagation compared to ordinary waves which travel shorter distances

14. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

SelectAnswer
ADownward bending due to aurora refraction
BDownward bending due to density variations in the atmosphere
CD-region skip
DE-region skip

15. - E4A09

When using a computer's soundcard input to digitize signals, what is the highest frequency signal that can be digitized without aliasing?

SelectAnswer
AIt depends on how the data is stored internally
BThe same as the sample rate
COne-half the sample rate
DOne-tenth the sample rate

16. - E4B15

Which of the following can be used as a relative measurement of the Q for a series-tuned circuit?

SelectAnswer
AThe frequency shift
BThe resonant frequency of the circuit
CThe inductance to capacitance ratio
DThe bandwidth of the circuit's frequency response

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

SelectAnswer
ADesensitization
BCross-modulation interference
CFrequency discrimination
DCapture effect

18. - E4D10

What does a third-order intercept level of 40 dBm mean with respect to receiver performance?

SelectAnswer
ASignals less than 40 dBm will not generate audible third-order intermodulation products
BThe receiver can tolerate signals up to 40 dB above the noise floor without producing third-order intermodulation products
CA pair of 40 dBm signals will theoretically generate a third-order intermodulation product with the same level as the input signals
DA pair of 1 mW input signals will produce a third-order intermodulation product which is 40 dB stronger than the input signal

19. - E4E02

Which of the following types of receiver noise can often be reduced with a DSP noise filter?

SelectAnswer
ABroadband white noise
BIgnition noise
CPower line noise
DAll of these choices are correct

20. - E5A13

What is an effect of increasing Q in a resonant circuit?

SelectAnswer
AParasitic effects are minimized
BFewer components are needed for the same performance
CPhase shift can become uncontrolled
DInternal voltages and circulating currents increase

21. - E5B07

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

SelectAnswer
A14.0 degrees with the voltage leading the current
B68.2 degrees with the voltage lagging the current
C14.0 degrees with the voltage lagging the current
D68.2 degrees with the voltage leading the current

22. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

SelectAnswer
AA negative real part
BA positive phase angle
CA positive real part
DA negative phase angle

23. - E5D16

What is the power factor of an R-L circuit having a 30 degree phase angle between the voltage and the current?

SelectAnswer
A1.73
B0.577
C0.866
D0.5

24. - E6A04

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

SelectAnswer
AAcceptor impurity
BN-type impurity
CDonor impurity
DInsulator impurity

25. - E6B08

Which of the following describes a type of semiconductor diode?

SelectAnswer
AElectrolytic rectifier
BMetal-semiconductor junction
CCMOS-field effect
DThermionic emission diode

26. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

SelectAnswer
ADifferential output capability
BImmune to damage from static discharge
CLower distortion
DLower power consumption

27. - E6D07

What is the usable frequency range of inductors that use toroidal cores, assuming a correct selection of core material for the frequency being used?

SelectAnswer
AFrom less than 20 Hz to approximately 300 MHz
BFrom approximately 10 Hz to no more than 3000 kHz
CFrom a few kHz to no more than 30 MHz
DFrom about 100 kHz to at least 1000 GHz

28. - E6E05

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

SelectAnswer
A-20 dBm
B2 dB
C44 dBm
D-10 dB

29. - E6F06

Which of these materials is affected the most by photoconductivity?

SelectAnswer
AA crystalline semiconductor
BA liquid semiconductor
CAn ordinary metal
DA heavy metal

30. - E7A09

What logical operation is performed by an exclusive NOR gate?

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

31. - E7B11

In Figure E7-1, what is the purpose of R3?

SelectAnswer
ASelf bias
BOutput load resistor
CEmitter bypass
DFixed bias

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

SelectAnswer
ACascode
BPi
COmega
DPi-L

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

SelectAnswer
AVoltage difference from input to output multiplied by output current
BOutput voltage multiplied by output current
CInput voltage divided by output current
DInput voltage multiplied by input current

34. - E7E07

What is meant by the term baseband in radio communications?

SelectAnswer
AThe basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
BThe frequency components present in the modulating signal
CThe unmodulated bandwidth of the transmitted signal
DThe lowest frequency band that the transmitter or receiver covers

35. - E7F12

What digital process is applied to I and Q signals in order to recover the baseband modulation information?

SelectAnswer
ASignal conditioning
BQuadrature mixing
CDecimation
DFast Fourier Transform

36. - E7G06

Which of the following is the most appropriate use of an op-amp active filter?

SelectAnswer
AFor smoothing power supply output
BAs a low-pass filter used between a transmitter and a transmission line
CAs an audio filter in a receiver
DAs a high-pass filter used to block RFI at the input to receivers

37. - E7H14

What is a phase-locked loop circuit?

SelectAnswer
AAn electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
BAn electronic circuit also known as a monostable multivibrator
CAn electronic circuit consisting of a precision push-pull amplifier with a differential input
DAn electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator

38. - E8A06

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

SelectAnswer
A25 to 1
B1 to 1
C100 to 1
D2.5 to 1

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

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

40. - E8C03

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

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

41. - E8D09

What is considered a good minimum IMD level for an idling PSK signal?

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

42. - E9A07

What is meant by antenna gain?

SelectAnswer
AThe ratio of the signal in the forward direction to that in the opposite direction
BThe ratio of the radiated signal strength of an antenna in the direction of maximum radiation to that of a reference antenna
CThe final amplifier gain minus the transmission line losses
DThe ratio of the amount of power radiated by an antenna compared to the transmitter output power

43. - E9B04

What may occur when a directional antenna is operated at different frequencies within the band for which it was designed?

SelectAnswer
AThe gain may change depending on frequency
BThe E-field and H-field patterns may reverse
CElement spacing limits could be exceeded
DFeed point impedance may become negative

44. - E9C05

What is an OCFD antenna?

SelectAnswer
AAn eight band dipole antenna using octophase filters
BA multiband dipole antenna using one-way circular polarization for frequency diversity
CA dipole feed approximately 1/3 the way from one end with a 4:1 balun to provide multiband operation
DA remotely tunable dipole antenna using orthogonally controlled frequency diversity

45. - E9D11

Which of the following types of conductors would be best for minimizing losses in a station's RF ground system?

SelectAnswer
AA cable with six or seven 18 gauge conductors in parallel
BA resistive wire, such as spark plug wire
CA wide flat copper strap
DA single 12 gauge or 10 gauge stainless steel wire

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

47. - E9F12

What impedance does a 1/4 wavelength transmission line present to a generator when the line is open at the far end?

SelectAnswer
AThe same as the input impedance to the generator
BVery low impedance
CThe same as the characteristic impedance of the line
DVery high impedance

48. - E9G03

Which of the following is often determined using a Smith chart?

SelectAnswer
ASatellite azimuth and elevation bearings
BBeam headings and radiation patterns
CImpedance and SWR values in transmission lines
DTrigonometric functions

49. - E9H07

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

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

50. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

SelectAnswer
AGround reflections and scattering make the field impedance vary with location
BAll of these choices are correct
CThe body reacts to electromagnetic radiation from both the E and H fields
DE field and H field radiation intensity peaks can occur at different locations

Figure E7-1