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

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1. - E1A08

If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

SelectAnswer
AThe control operator of the packet bulletin board station
BThe control operator of the originating station
CThe control operators of all the stations in the system not authenticating the source from which they accept communications
DThe control operators of all the stations in the system

2. - E1B01

Which of the following constitutes a spurious emission?

SelectAnswer
AAn emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
BAny transmitted signal that unintentionally interferes with another licensed radio station
CA signal transmitted to prevent its detection by any station other than the intended recipient
DAn amateur station transmission made at random without the proper call sign identification

3. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

SelectAnswer
ACEPT agreement
BAll of these choices are correct
CITU reciprocal license
DIARP agreement

4. - E1D01

What is the definition of the term telemetry?

SelectAnswer
ATwo-way single channel transmissions of data
BOne-way transmission that initiates, modifies, or terminates the functions of a device at a distance
COne-way transmission of measurements at a distance from the measuring instrument
DTwo-way radiotelephone transmissions in excess of 1000 feet

5. - E1E08

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

SelectAnswer
AFriends of the VE
BAll of these choices are correct
CRelatives of the VE as listed in the FCC rules
DEmployees of the VE

6. - E1F02

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

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

7. - E2A10

Why may the received signal from an amateur satellite exhibit a rapidly repeating fading effect?

SelectAnswer
ABecause the satellite is spinning
BBecause of ionospheric absorption
CBecause of the satellite's low orbital altitude
DBecause of the Doppler Effect

8. - E2B06

What is vestigial sideband modulation?

SelectAnswer
AA type of modulation in which one sideband is inverted
BAmplitude modulation in which one complete sideband and a portion of the other are transmitted
CSpread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation
DNarrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier

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
BThe ARRL section of the remote station
C/ followed by the USPS two letter abbreviation for the state in which the remote station is located
DNo additional indicator is required

10. - E2D12

How does JT65 improve EME communications?

SelectAnswer
AAll of these choices are correct
BIt supplies signals to guide the antenna to track the Moon
CIt controls the receiver to track Doppler shift
DIt can decode signals many dB below the noise floor using FEC

11. - E2E12

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

SelectAnswer
ARemote
BLocal
CALE can use any type of control
DAutomatic

12. - E3A13

Which emission mode is best for aurora propagation?

SelectAnswer
AFM
BRTTY
CCW
DSSB

13. - E3B02

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

SelectAnswer
A2500 miles
B5000 miles
C1000 miles
D7500 miles

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

SelectAnswer
AIt peaks at roughly 14 MHz
BIt increases
CIt stays the same
DIt decreases

15. - E4A05

What might be an advantage of a digital vs an analog oscilloscope?

SelectAnswer
AAutomatic amplitude and frequency numerical readout
BStorage of traces for future reference
CAll of these choices are correct
DManipulation of time base after trace capture

16. - E4B09

What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?

SelectAnswer
AThere is possibly a short to ground in the feed line
BThere is more power going into the antenna
CThere is an impedance mismatch between the antenna and feed line
DThe transmitter is not properly neutralized

17. - E4C11

Which of the following is a desirable amount of selectivity for an amateur SSB phone receiver?

SelectAnswer
A1 kHz
B4.8 kHz
C4.2 kHz
D2.4 kHz

18. - E4D09

What is the purpose of the preselector in a communications receiver?

SelectAnswer
ATo store often-used frequencies
BTo increase rejection of unwanted signals
CTo allow selection of the optimum RF amplifier device
DTo provide a range of AGC time constants

19. - E4E09

What undesirable effect can occur when using an IF noise blanker?

SelectAnswer
AThe audio frequency bandwidth of the received signal might be compressed
BNearby signals may appear to be excessively wide even if they meet emission standards
CReceived audio in the speech range might have an echo effect
DFM signals can no longer be demodulated

20. - E5A06

What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

SelectAnswer
AIt is at a minimum
BIt equals 1 divided by the quantity 2 times Pi, multiplied by the square root of inductance L multiplied by capacitance C
CIt is at a maximum
DIt equals 2 multiplied by Pi, multiplied by frequency, multiplied by inductance

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
AAn exponential discharge rate of one
BOne discharge period
COne time constant
DA discharge factor of one

22. - E5C10

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

SelectAnswer
AThe sum of the reactive and resistive components
BReactive component
CResistive component
DThe difference between the resistive and reactive components

23. - E5D07

What determines the strength of the magnetic field around a conductor?

SelectAnswer
AThe diameter of the conductor
BThe amount of current flowing through the conductor
CThe resistance divided by the current
DThe ratio of the current to the resistance

24. - E6A05

What is the alpha of a bipolar junction transistor?

SelectAnswer
AThe change of collector current with respect to emitter current
BThe change of collector current with respect to base current
CThe change of collector current with respect to gate current
DThe change of base current with respect to collector current

25. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

SelectAnswer
AZener diode
BTunnel diode
CSilicon-controlled rectifier
DVaractor diode

26. - E6C06

Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?

SelectAnswer
AThe input switching threshold is about one-half the power supply voltage
BInput signals are stronger
CThe input switching threshold is about two times the power supply voltage
DLarger bypass capacitors are used in CMOS circuit design

27. - E6D08

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

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

28. - E6E02

Which of the following device packages is a through-hole type?

SelectAnswer
ADIP
BBall grid array
CSOT
DPLCC

29. - E6F07

What is a solid state relay?

SelectAnswer
AA mechanical relay that latches in the on or off state each time it is pulsed
BA relay using transistors to drive the relay coil
CA passive delay line
DA device that uses semiconductors to implement the functions of an electromechanical relay

30. - E7A04

How many flip-flops are required to divide a signal frequency by 4?

SelectAnswer
A4
B8
C2
D1

31. - E7B16

What is the effect of intermodulation products in a linear power amplifier?

SelectAnswer
AAll of these choices are correct
BCreation of parasitic oscillations
CLow efficiency
DTransmission of spurious signals

32. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

SelectAnswer
AA Chebyshev filter
BA Butterworth filter
CAn active LC filter
DA passive op-amp filter

33. - E7D06

What is the purpose of Q1 in the circuit shown in Figure E7-3?

SelectAnswer
AIt provides negative feedback to improve regulation
BIt provides a constant load for the voltage source
CIt provides D1 with current
DIt increases the current-handling capability of the regulator

34. - E7E04

What is one way a single-sideband phone signal can be generated?

SelectAnswer
ABy driving a product detector with a DSB signal
BBy using a reactance modulator followed by a mixer
CBy using a loop modulator followed by a mixer
DBy using a balanced modulator followed by a filter

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
A4 bits
B6 bits
C10 bits
D8 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-2.3 volts
B0.23 volts
C2.3 volts
D-0.23 volts

37. - E7H13

Which of the following is a technique for providing highly accurate and stable oscillators needed for microwave transmission and reception?

SelectAnswer
AAll of these choices are correct
BUse a rubidium stabilized reference oscillator
CUse a GPS signal reference
DUse a temperature-controlled high Q dielectric resonator

38. - E8A06

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

SelectAnswer
A100 to 1
B1 to 1
C2.5 to 1
D25 to 1

39. - E8B09

What is meant by deviation ratio?

SelectAnswer
AThe ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
BThe ratio of the carrier center frequency to the audio modulating frequency
CThe ratio of the highest audio modulating frequency to the average audio modulating frequency
DThe ratio of the audio modulating frequency to the center carrier frequency

40. - E8C08

How does ARQ accomplish error correction?

SelectAnswer
AIf errors are detected, redundant data is substituted
BSpecial binary codes provide automatic correction
CSpecial polynomial codes provide automatic correction
DIf errors are detected, a retransmission is requested

41. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

SelectAnswer
ABaudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
BBaudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
CBaudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
DBaudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code

42. - E9A03

Why would one need to know the feed point impedance of an antenna?

SelectAnswer
ATo measure the near-field radiation density from a transmitting antenna
BTo calculate the front-to-back ratio of the antenna
CTo calculate the front-to-side ratio of the antenna
DTo match impedances in order to minimize standing wave ratio on the transmission line

43. - E9B09

What type of computer program technique is commonly used for modeling antennas?

SelectAnswer
AGraphical analysis
BCalculus differentiation with respect to physical properties
CMethod of Moments
DMutual impedance analysis

44. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

SelectAnswer
AOmni-directional
BCardioid
CA Figure-8 broadside to the axis of the array
DA Figure-8 end-fire along the axis of the array

45. - E9D04

Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?

SelectAnswer
ATo maximize losses
BTo swamp out harmonics
CTo minimize losses
DTo minimize the Q

46. - E9E12

What is the primary purpose of a phasing line when used with an antenna having multiple driven elements?

SelectAnswer
AIt makes sure the antenna has a low-angle radiation pattern
BIt allows single-band antennas to operate on other bands
CIt ensures that each driven element operates in concert with the others to create the desired antenna pattern
DIt prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter

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
BAll of these choices are correct
CFoam dielectric has lower safe operating voltage limits
DFoam dielectric has lower loss per unit of length

48. - E9G11

How are the wavelength scales on a Smith chart calibrated?

SelectAnswer
AIn fractions of transmission line electrical frequency
BIn fractions of transmission line electrical wavelength
CIn fractions of antenna electrical frequency
DIn fractions of antenna electrical wavelength

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

SelectAnswer
AA large circularly polarized antenna
BOne or more turns of wire wound in the shape of a large open coil
CA vertical antenna coupled to a feed line through an inductive loop of wire
DA small coil of wire tightly wound around a toroidal ferrite core

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
BLocalized heating of the body from RF exposure in excess of the MPE limits
CHearing loss caused by high voltage corona discharge
DBlood clotting from the intense magnetic field

Figure E7-3

Figure E7-4