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

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1. - E1A03

With your transceiver displaying the carrier frequency of phone signals, you hear a station calling CQ on 14.349 MHz USB. Is it legal to return the call using upper sideband on the same frequency?

SelectAnswer
ANo, U.S. stations are not permitted to use phone emissions above 14.340 MHz
BYes, because you were not the station calling CQ
CNo, the sideband will extend beyond the band edge
DYes, because the displayed frequency is within the 20 meter band

2. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

SelectAnswer
ASpecific segments in the amateur service MF, HF, VHF and UHF bands
BMilitary Auxiliary Radio System (MARS) channels
CSpecific local government channels
DAll amateur service frequencies authorized to the control operator

3. - E1C10

What types of amateur stations may automatically retransmit the radio signals of other amateur stations?

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

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 changing its orbit whenever such a change is ordered by NASA
DThe space station must be capable of terminating transmissions by telecommand when directed by the FCC

5. - E1E14

For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

SelectAnswer
ANo expenses are authorized for reimbursement
BTeaching an amateur operator license examination preparation course
CProviding amateur operator license examination preparation training materials
DPreparing, processing, administering and coordinating an examination for an amateur radio license

6. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

SelectAnswer
A222 MHz - 223 MHz
B53 MHz - 54 MHz
C440 MHz - 450 MHz
D420 MHz - 430 MHz

7. - E2A12

What is one way to predict the location of a satellite at a given time?

SelectAnswer
ABy subtracting the mean anomaly from the orbital inclination
BBy adding the mean anomaly to the orbital inclination
CBy calculations using the Keplerian elements for the specified satellite
DBy means of the Doppler data for the specified satellite

8. - E2B05

Which of the following is an advantage of using vestigial sideband for standard fast- scan TV transmissions?

SelectAnswer
AVestigial sideband provides high frequency emphasis to sharpen the picture
BVestigial sideband reduces bandwidth while allowing for simple video detector circuitry
CThe vestigial sideband carries the audio information
DThe vestigial sideband contains chroma information

9. - E2C12

What might help to restore contact when DX signals become too weak to copy across an entire HF band a few hours after sunset?

SelectAnswer
ASwitch to a lower frequency HF band
BSwitch to a higher frequency HF band
CWait 90 minutes or so for the signal degradation to pass
DWait 24 hours before attempting another communication on the band

10. - E2D14

What is one advantage of using JT65 coding?

SelectAnswer
AThe ability to decode signals which have a very low signal to noise ratio
BEasily copied by ear if necessary
CUses only a 65 Hz bandwidth
DPermits fast-scan TV transmissions over narrow bandwidth

11. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

SelectAnswer
APSK31
BMT63
CPACTOR
DRTTY

12. - E3A13

Which emission mode is best for aurora propagation?

SelectAnswer
AFM
BCW
CRTTY
DSSB

13. - E3B10

What is the cause of gray-line propagation?

SelectAnswer
AAt midday, the Sun super heats the ionosphere causing increased refraction of radio waves
BAt twilight and sunrise, D-layer absorption is low while E-layer and F-layer propagation remains high
CIn darkness, solar absorption drops greatly while atmospheric ionization remains steady
DAt mid-afternoon, the Sun heats the ionosphere decreasing radio wave refraction and the MUF

14. - E3C04

What does the value of Bz (B sub Z) represent?

SelectAnswer
ADuration of long-delayed echoes
BGeomagnetic field stability
CDirection and strength of the interplanetary magnetic field
DCritical frequency for vertical transmissions

15. - E4A06

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

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

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
C1.4652 Hz
D14.652 Hz

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
CCapture effect
DFrequency discrimination

18. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

SelectAnswer
AA Class D final amplifier
BA properly terminated circulator at the output of the transmitter
CA band-pass filter in the feed line between the transmitter and receiver
DA Class C final amplifier

19. - E4E11

Which is the most likely cause if you are hearing combinations of local AM broadcast signals within one or more of the MF or HF ham bands?

SelectAnswer
AThe broadcast station is transmitting an over-modulated signal
BYour station receiver IF amplifier stage is defective
CYou are receiving sky wave signals from a distant station
DNearby corroded metal joints are mixing and re-radiating the broadcast signals

20. - E5A14

What is the resonant frequency of a series RLC circuit if R is 22 ohms, L is 50 microhenrys and C is 40 picofarads?

SelectAnswer
A44.72 MHz
B1.78 MHz
C22.36 MHz
D3.56 MHz

21. - E5B13

What letter is commonly used to represent susceptance?

SelectAnswer
AX
BB
CG
DY

22. - E5C17

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?

SelectAnswer
APoint 5
BPoint 1
CPoint 8
DPoint 3

23. - E5D08

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

SelectAnswer
AElectromechanical energy
BThermodynamic energy
CPotential energy
DKinetic energy

24. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

SelectAnswer
ABeta cutoff frequency
BCorner frequency
CAlpha cutoff frequency
DAlpha rejection frequency

25. - E6B03

What special type of diode is capable of both amplification and oscillation?

SelectAnswer
AZener
BTunnel
CJunction
DPoint contact

26. - E6C11

In Figure E6-5, what is the schematic symbol for the NOT operation (inverter)?

SelectAnswer
A6
B4
C5
D2

27. - E6D08

What is one reason for using powdered-iron cores rather than ferrite cores in an inductor?

SelectAnswer
APowdered-iron cores generally require fewer turns to produce a given inductance
BPowdered-iron cores generally have greater initial permeability
CPowdered-iron cores use smaller diameter wire for the same inductance
DPowdered-iron cores generally maintain their characteristics at higher currents

28. - E6E12

Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?

SelectAnswer
AEnhanced sensitivity to light
BHigh-voltage insulating ability
CTo provide a low-pass frequency response
DBetter dissipation of heat

29. - E6F04

What is the photovoltaic effect?

SelectAnswer
AThe tendency of a battery to discharge when used outside
BThe conversion of light to electrical energy
CThe conversion of electrical energy to mechanical energy
DThe conversion of voltage to current when exposed to light

30. - E7A03

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

SelectAnswer
AAn OR gate
BAn XOR gate
CA flip-flop
DA multiplexer

31. - E7B06

Which of the following amplifier types reduces or eliminates even order harmonics?

SelectAnswer
AClass C
BPush-push
CClass AB
DPush-pull

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 Pi-network with an additional series inductor on the output
CA matching network in which all components are isolated from ground
DA Phase Inverter Load network

33. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

SelectAnswer
AA series current source
BA shunt current source
CA shunt regulator
DA series regulator

34. - E7E05

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

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

35. - E7F06

What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

SelectAnswer
A10 bits
B8 bits
C6 bits
D4 bits

36. - E7G09

What will be the output voltage of the circuit shown in Figure E7-4 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

SelectAnswer
A-0.23 volts
B2.3 volts
C-2.3 volts
D0.23 volts

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

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

38. - E8A12

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

SelectAnswer
AAll of these choices are correct
BDigital signals can be regenerated multiple times without error
CLess complex circuitry is required for digital signal generation and detection
DDigital signals always occupy a narrower bandwidth

39. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

SelectAnswer
A2000
B6000
C3
D1/3

40. - E8C02

What is the definition of symbol rate in a digital transmission?

SelectAnswer
AThe rate at which the waveform of a transmitted signal changes to convey information
BThe number of control characters in a message packet
CThe duration of each bit in a message sent over the air
DThe number of characters carried per second by the station-to-station link

41. - E8D08

What parameter might indicate that excessively high input levels are causing distortion in an AFSK signal?

SelectAnswer
ABaud rate
BRepeat Request Rate (RRR)
CSignal to noise ratio
DIntermodulation Distortion (IMD)

42. - E9A18

What term describes station output, taking into account all gains and losses?

SelectAnswer
APower factor
BEffective radiated power
CHalf-power bandwidth
DApparent power

43. - E9B10

What is the principle of a Method of Moments analysis?

SelectAnswer
AA wire is modeled as a single sine-wave current generator
BA wire is modeled as a series of segments, each having a distinct value of voltage across it
CA wire is modeled as a series of points, each having a distinct location in space
DA wire is modeled as a series of segments, each having a uniform value of current

44. - E9C05

What is an OCFD antenna?

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

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

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. - E9F15

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

SelectAnswer
AVery low impedance
BThe same as the output impedance of the generator
CVery high impedance
DThe same as the characteristic impedance of the line

48. - E9G05

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

SelectAnswer
AElevation angle radiation pattern chart
BAzimuth angle radiation pattern chart
CFree space radiation directivity chart
DSmith chart

49. - E9H04

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

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

50. - E0A05

What is one of the potential hazards of using microwaves in the amateur radio bands?

SelectAnswer
AMicrowaves are ionizing radiation
BThe high gain antennas commonly used can result in high exposure levels
CThe extremely high frequency energy can damage the joints of antenna structures
DMicrowaves often travel long distances by ionospheric reflection

Figure E5-2

Figure E6-5

Figure E7-4

Figure E9-3