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

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1. - E1A07

Which amateur band requires transmission on specific channels rather than on a range of frequencies?

SelectAnswer
A17 meter band
B30 meter band
C60 meter band
D12 meter band

2. - E1B11

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHZ?

SelectAnswer
AAt least 63 dB below
BAt least 53 dB below
CAt least 43 dB below
DAt least 73 dB below

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

SelectAnswer
ABusiness-related messages for non-profit organizations
BAll of these choices are correct
CMessages intended for connection to users of the maritime satellite service
DCommunications incidental to the purpose of the amateur service and remarks of a personal nature

4. - E1D02

What is the amateur satellite service?

SelectAnswer
AA radio communications service using amateur radio stations on satellites
BA spacecraft launching service for amateur-built satellites
CA radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
DA radio communications service using stations on Earth satellites for public service broadcast

5. - E1E09

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

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

6. - E1F12

Who may be the control operator of an auxiliary station?

SelectAnswer
AOnly Amateur Extra Class operators
BAny licensed amateur operator
COnly Technician, General, Advanced or Amateur Extra Class operators
DOnly General, Advanced or Amateur Extra Class operators

7. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

SelectAnswer
AA circularly polarized antenna
BA log-periodic dipole array
CAn isotropic antenna
DA linearly polarized antenna

8. - E2B17

What is the approximate bandwidth of a slow-scan TV signal?

SelectAnswer
A2 MHz
B6 MHz
C600 Hz
D3 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/ followed by the USPS two letter abbreviation for the state in which the remote station is located
BNo additional indicator is required
CThe ARRL section of the remote station
D/R# where # is the district of the remote station

10. - E2D13

What type of modulation is used for JT65 contacts?

SelectAnswer
AIEEE 802.11
BMulti-tone AFSK
CRTTY
DPSK

11. - E2E11

What is the difference between direct FSK and audio FSK?

SelectAnswer
ADirect FSK applies the data signal to the transmitter VFO
BAudio FSK has a superior frequency response
CDirect FSK uses a DC-coupled data connection
DAudio FSK can be performed anywhere in the transmit chain

12. - E3A06

Which of the following is required for microwave propagation via rain scatter?

SelectAnswer
ARain droplets must be electrically charged
BRain droplets must be within the E layer
CAll of these choices are correct
DThe rain must be within radio range of both stations

13. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

SelectAnswer
A5000 miles
B1000 miles
C2500 miles
D7500 miles

14. - E3C13

What type of polarization is best for ground-wave propagation?

SelectAnswer
AHorizontal
BElliptical
CCircular
DVertical

15. - E4A14

What is the purpose of the prescaler function on a frequency counter?

SelectAnswer
AIt divides a higher frequency signal so a low-frequency counter can display the input frequency
BIt amplifies low level signals for more accurate counting
CIt multiplies a higher frequency signal so a low-frequency counter can display the operating frequency
DIt prevents oscillation in a low-frequency counter circuit

16. - E4B12

What is the significance of voltmeter sensitivity expressed in ohms per volt?

SelectAnswer
AThe full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter
BWhen used as a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test
CWhen used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit
DWhen used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed

17. - E4C03

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

SelectAnswer
ACross-modulation interference
BDesensitization
CCapture effect
DFrequency discrimination

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
B146.34 MHz and 146.61 MHz
C146.88 MHz and 146.34 MHz
D173.35 MHz and 139.40 MHz

19. - E4E01

Which of the following types of receiver noise can often be reduced by use of a receiver noise blanker?

SelectAnswer
AHeterodyne interference
BBroadband white noise
CAll of these choices are correct
DIgnition noise

20. - E5A17

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

SelectAnswer
AMatching range is increased
BMatching bandwidth is increased
CMatching bandwidth is decreased
DIt has no effect on impedance matching

21. - E5B02

What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

SelectAnswer
AOne discharge period
BOne time constant
CAn exponential discharge rate of one
DA discharge factor of one

22. - E5C09

When using rectangular coordinates to graph the impedance of a circuit, what does the horizontal axis represent?

SelectAnswer
AReactive component
BResistive component
CThe sum of the reactive and resistive components
DThe difference between the resistive and reactive components

23. - E5D04

Why are short connections necessary at microwave frequencies?

SelectAnswer
ATo increase neutralizing resistance
BTo reduce phase shift along the connection
CBecause of ground reflections
DTo reduce noise figure

24. - E6A01

In what application is gallium arsenide used as a semiconductor material in preference to germanium or silicon?

SelectAnswer
AIn very low frequency RF circuits
BIn microwave circuits
CIn high-power audio circuits
DIn high-current rectifier circuits

25. - E6B08

Which of the following describes a type of semiconductor diode?

SelectAnswer
AThermionic emission diode
BElectrolytic rectifier
CMetal-semiconductor junction
DCMOS-field effect

26. - E6C05

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

SelectAnswer
ADifferential output capability
BLower power consumption
CLower distortion
DImmune to damage from static discharge

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 use smaller diameter wire for the same inductance
CPowdered-iron cores generally have greater initial permeability
DPowdered-iron cores generally maintain their characteristics at higher currents

28. - E6E10

What is the packaging technique in which leadless components are soldered directly to circuit boards?

SelectAnswer
ADirect soldering
BSurface mount
CVirtual lead mounting
DStripped lead

29. - E6F03

What is the most common configuration of an optoisolator or optocoupler?

SelectAnswer
AA lens and a photomultiplier
BA frequency modulated helium-neon laser
CAn amplitude modulated helium-neon laser
DAn LED and a phototransistor

30. - E7A02

What is the function of a decade counter digital IC?

SelectAnswer
AIt adds two decimal numbers together
BIt produces one output pulse for every ten input pulses
CIt decodes a decimal number for display on a seven segment LED display
DIt produces ten output pulses for every input pulse

31. - E7B09

Which of the following describes how the loading and tuning capacitors are to be adjusted when tuning a vacuum tube RF power amplifier that employs a Pi-network output circuit?

SelectAnswer
AThe tuning capacitor is set to maximum capacitance and the loading capacitor is adjusted for minimum plate permissible current
BThe loading capacitor is set to maximum capacitance and the tuning capacitor is adjusted for minimum allowable plate current
CThe tuning capacitor is adjusted for minimum plate current, and the loading capacitor is adjusted for maximum permissible plate current
DThe loading capacitor is adjusted to minimum plate current while alternately adjusting the tuning capacitor for maximum allowable plate current

32. - E7C03

What advantage does a Pi-L-network have over a regular Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

SelectAnswer
AGreater transformation range
BLower losses
CHigher efficiency
DGreater harmonic suppression

33. - E7D08

What type of circuit is shown in Figure E7-3?

SelectAnswer
AEmitter follower
BLinear voltage regulator
CSwitching voltage regulator
DGrounded emitter amplifier

34. - E7E12

What is a frequency discriminator stage in a FM receiver?

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

35. - E7F01

What is meant by direct digital conversion as applied to software defined radios?

SelectAnswer
AA switching mixer is used to generate I and Q signals directly from the RF input
BIncoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal
CSoftware is converted from source code to object code during operation of the receiver
DIncoming RF is converted to a control voltage for a voltage controlled oscillator

36. - E7G04

What is meant by the term op-amp input offset voltage?

SelectAnswer
AThe output voltage of the op-amp minus its input voltage
BThe differential input voltage needed to bring the open loop output voltage to zero
CThe potential between the amplifier input terminals of the op-amp in an open loop condition
DThe difference between the output voltage of the op-amp and the input voltage required in the immediately following stage

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

SelectAnswer
ANP0 capacitors
BNon-inductive resistors
CToroidal inductors
DWirewound resistors

38. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all of its harmonics?

SelectAnswer
AA sine wave
BA sawtooth wave
CA square wave
DA cosine wave

39. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

SelectAnswer
AOFDM signals are not allowed on amateur bands
BHigh speed digital modes
CExtremely low-power contacts
DEME

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
BThis results in the least possible transmitted bandwidth for the particular mode
CIt improves carrier suppression
DAll of these choices are correct

41. - E8D08

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

SelectAnswer
ABaud rate
BSignal to noise ratio
CIntermodulation Distortion (IMD)
DRepeat Request Rate (RRR)

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
CThe settings of an antenna tuner at the transmitter
DSunspot activity and time of day

43. - E9B08

How can the approximate beam-width in a given plane of a directional antenna be determined?

SelectAnswer
AMeasure the ratio of the signal strengths of the radiated power lobes from the front and side of the antenna
BMeasure the ratio of the signal strengths of the radiated power lobes from the front and rear of the antenna
CDraw two imaginary lines through the ends of the elements and measure the angle between the lines
DNote the two points where the signal strength of the antenna is 3 dB less than maximum and compute the angular difference

44. - E9C15

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with its height above ground?

SelectAnswer
AThe horizontal beam width increases with height
BThe horizontal beam width decreases with height
CThe main lobe takeoff angle decreases with increasing height
DThe main lobe takeoff angle increases with increasing height

45. - E9D12

Which of the following would provide the best RF ground for your station?

SelectAnswer
AAn electrically short connection to a metal water pipe
BAn electrically short connection to 3 or 4 interconnected ground rods via a series RF choke
CAn electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
DA 50 ohm resistor connected to ground

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

SelectAnswer
AConnect a series-resonant LC network across the antenna feed terminals
BUse the universal stub matching technique
CConnect a parallel-resonant LC network across the antenna feed terminals
DUse a 50 ohm 1:1 balun between the antenna and feed line

47. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

SelectAnswer
ASkin effect is less pronounced in the coaxial cable
BThe characteristic impedance is higher in a parallel feed line
CThe surge impedance is higher in a parallel feed line
DElectrical signals move more slowly in a coaxial cable than in air

48. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

SelectAnswer
AAntenna-length circles
BStanding wave ratio circles
CRadiation-pattern circles
DCoaxial-length circles

49. - E9H06

What is the triangulation method of direction finding?

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

50. - E0A05

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

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

Figure E7-3