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

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1. - E1A05

What is the maximum power output permitted on the 60 meter band?

SelectAnswer
A50 watts PEP effective radiated power relative to an isotropic radiator
B50 watts PEP effective radiated power relative to a dipole
C100 watts PEP effective radiated power relative to an isotropic radiator
D100 watts PEP effective radiated power relative to the gain of a half-wave dipole

2. - E1B05

What is the National Radio Quiet Zone?

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

3. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

SelectAnswer
AUnder local control there is no control operator
BUnder local control a control operator is not required to be present at a control point
CUnder automatic control the control operator is not required to be present at the control point
DUnder automatic control there is no control operator

4. - E1D06

Which of the following is a requirement of a space station?

SelectAnswer
AAll of these choices are correct
BThe space station must cease all transmissions after 5 years
CThe space station must be capable of terminating transmissions by telecommand when directed by the FCC
DThe space station must be capable of changing its orbit whenever such a change is ordered by NASA

5. - E1E08

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

SelectAnswer
AFriends of the VE
BEmployees of the VE
CRelatives of the VE as listed in the FCC rules
DAll of these choices are correct

6. - E1F12

Who may be the control operator of an auxiliary station?

SelectAnswer
AAny licensed amateur operator
BOnly Technician, General, Advanced or Amateur Extra Class operators
COnly Amateur Extra Class operators
DOnly General, Advanced or Amateur Extra Class operators

7. - E2A02

What is the direction of a descending pass for an amateur satellite?

SelectAnswer
AFrom west to east
BFrom east to west
CFrom north to south
DFrom south to north

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
B15 KHz
C20 KHz
D10 KHz

9. - E2C13

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control where the transmitter is located in the U.S.?

SelectAnswer
A/R# where # is the district of the remote station
BNo additional indicator is required
CThe ARRL section of the remote station
D/ followed by the USPS two letter abbreviation for the state in which the remote station is located

10. - E2D13

What type of modulation is used for JT65 contacts?

SelectAnswer
AIEEE 802.11
BMulti-tone AFSK
CPSK
DRTTY

11. - E2E03

How is the timing of JT65 contacts organized?

SelectAnswer
ABy exchanging ACK/NAK packets
BIt depends on the lunar phase
CStations take turns on alternate days
DAlternating transmissions at 1 minute intervals

12. - E3A05

Tropospheric propagation of microwave signals often occurs along what weather related structure?

SelectAnswer
ALightning discharges
BGray-line
CSprites and jets
DWarm and cold fronts

13. - E3B12

What is the primary characteristic of chordal hop propagation?

SelectAnswer
APropagation away from the great circle bearing between stations
BPropagation across the geomagnetic equator
CSuccessive ionospheric reflections without an intermediate reflection from the ground
DSignals reflected back toward the transmitting station

14. - E3C14

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

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

15. - E4A06

What is the effect of aliasing in a digital or computer-based oscilloscope?

SelectAnswer
AFalse signals are displayed
BAll signals will have a DC offset
CFalse triggering occurs
DCalibration of the vertical scale is no longer valid

16. - E4B15

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

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

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

SelectAnswer
AIt reduces receiver sensitivity
BIt decreases receiver third-order intermodulation distortion dynamic range
CIt limits the receiver's ability to receive strong signals
DIt can cause strong signals on nearby frequencies to interfere with reception of weak signals

18. - E4D02

Which of the following describes two problems caused by poor dynamic range in a communications receiver?

SelectAnswer
AOscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
BOscillator instability and severe audio distortion of all but the strongest received signals
CCross-modulation of the desired signal and desensitization from strong adjacent signals
DCross-modulation of the desired signal and insufficient audio power to operate the speaker

19. - E4E15

Which of the following can cause shielded cables to radiate or receive interference?

SelectAnswer
ACommon mode currents on the shield and conductors
BUse of braided shielding material
CTying all ground connections to a common point resulting in differential mode currents in the shield
DLow inductance ground connections at both ends of the shield

20. - E5A17

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

SelectAnswer
AIt has no effect on impedance matching
BMatching range is increased
CMatching bandwidth is decreased
DMatching bandwidth is increased

21. - E5B12

What is admittance?

SelectAnswer
AThe inverse of impedance
BThe turns ratio of a transformer
CThe unit used for Q factor
DThe term for the gain of a field effect transistor

22. - E5C14

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 400 ohm resistor and a 38 picofarad capacitor at 14 MHz?

SelectAnswer
APoint 4
BPoint 5
CPoint 6
DPoint 2

23. - E5D18

How many watts are consumed in a circuit having a power factor of 0.71 if the apparent power is 500VA?

SelectAnswer
A1.42 mW
B252 W
C704 W
D355 W

24. - E6A17

What are the names of the three terminals of a field-effect transistor?

SelectAnswer
AGate 1, gate 2, drain
BEmitter, base, collector
CEmitter, base 1, base 2
DGate, drain, source

25. - E6B08

Which of the following describes a type of semiconductor diode?

SelectAnswer
AMetal-semiconductor junction
BElectrolytic rectifier
CCMOS-field effect
DThermionic emission diode

26. - E6C08

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

SelectAnswer
A1
B3
C4
D2

27. - E6D15

What is current in the primary winding of a transformer called if no load is attached to the secondary?

SelectAnswer
ADirect current
BStabilizing current
CMagnetizing current
DExcitation current

28. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

SelectAnswer
AControlled gain, low noise figure, and constant input and output impedance over the specified frequency range
BPlate current that is controlled by a control grid
CNearly infinite gain, very high input impedance, and very low output impedance
DThe ability to retrieve information from a single signal even in the presence of other strong signals

29. - E6F09

What is the efficiency of a photovoltaic cell?

SelectAnswer
AThe open-circuit voltage divided by the short-circuit current under full illumination
BThe relative fraction of light that is converted to current
CThe output RF power divided by the input DC power
DThe effective payback period

30. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

SelectAnswer
AA multiplexer
BAn OR gate
CAn XOR gate
DA flip-flop

31. - E7B17

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

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

32. - E7C12

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

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

33. - E7D09

What is the main reason to use a charge controller with a solar power system?

SelectAnswer
APrevention of battery damage due to overcharge
BPrevention of battery undercharge
CControl of electrolyte levels during battery discharge
DMatching of day and night charge rates

34. - E7E12

What is a frequency discriminator stage in a FM receiver?

SelectAnswer
AAn FM generator circuit
BA circuit for detecting FM signals
CAn automatic band-switching circuit
DA circuit for filtering two closely adjacent signals

35. - E7F15

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

SelectAnswer
AAll of these choices are correct
BFIR filters are easier to implement for a given set of passband rolloff requirements
CFIR filters delay all frequency components of the signal by the same amount
DFIR filters can respond faster to impulses

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 gain but increase Q
CIncrease both gain and Q
DRestrict Q but increase gain

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

SelectAnswer
AThrough a tapped coil
BThrough a neutralizing capacitor
CThrough link coupling
DThrough a quartz crystal

38. - E8A11

What type of information can be conveyed using digital waveforms?

SelectAnswer
AData
BVideo signals
CHuman speech
DAll of these choices are correct

39. - E8B10

What describes frequency division multiplexing?

SelectAnswer
AThe transmitted signal jumps from band to band at a predetermined rate
BTwo or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
CThe transmitted signal is divided into packets of information
DTwo or more information streams are merged into a baseband, which then modulates the transmitter

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

41. - E8D01

Why are received spread spectrum signals resistant to interference?

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

42. - E9A02

What antenna has no gain in any direction?

SelectAnswer
AQuarter-wave vertical
BHalf-wave dipole
CIsotropic antenna
DYagi

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

SelectAnswer
A28 dB
B15 dB
C3 dB
D24 dB

44. - E9C09

What is a G5RV antenna?

SelectAnswer
AA wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun
BA phased array antenna consisting of multiple loops
CA multi-band trap antenna
DA multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line

45. - E9D05

What is a disadvantage of using a multiband trapped antenna?

SelectAnswer
AIt must be neutralized
BIt is too sharply directional at lower frequencies
CIt radiates the harmonics and fundamental equally well
DIt might radiate harmonics

46. - E9E06

What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?

SelectAnswer
APi-network
BA series capacitor
CPi-L-network
DA shunt inductor

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 higher velocity factor
BFoam dielectric has lower safe operating voltage limits
CAll of these choices are correct
DFoam dielectric has lower loss per unit of length

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
AImpedance axis
BReactance axis
CPolar axis
DPrime axis

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
BA fixed receiving station uses three different antennas to plot the location of the signal source
CA fixed receiving station plots three headings to the signal source
DThe geometric angles of sky waves from the source are used to determine its position

50. - E0A01

What is the primary function of an external earth connection or ground rod?

SelectAnswer
AReduce RF current flow between pieces of equipment
BReduce RFI to telephones and home entertainment systems
CLightning protection
DReduce received noise

Figure E5-2

Figure E6-5

Figure E9-2

Figure E9-3