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

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

3. - E1C12

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

SelectAnswer
AAll of these choices are correct
BBusiness-related messages for non-profit organizations
CCommunications incidental to the purpose of the amateur service and remarks of a personal nature
DMessages intended for connection to users of the maritime satellite service

4. - E1D05

What class of licensee is authorized to be the control operator of a space station?

SelectAnswer
AAny class with appropriate operator privileges
BAll except Technician Class
COnly Amateur Extra Class
DOnly General, Advanced or Amateur Extra Class

5. - E1E06

Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

SelectAnswer
AThe VE session manager
BThe FCC
CThe VEC coordinating the session
DEach administering VE

6. - E1F07

When may an amateur station send a message to a business?

SelectAnswer
AWhen transmitting international third-party communications
BWhen the total money involved does not exceed $25
CWhen the control operator is employed by the FCC or another government agency
DWhen neither the amateur nor his or her employer has a pecuniary interest in the communications

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 linearly polarized antenna
CA log-periodic dipole array
DAn isotropic antenna

8. - E2B18

On which of the following frequencies is one likely to find FM ATV transmissions?

SelectAnswer
A1255 MHz
B29.6 MHz
C52.525 MHz
D14.230 MHz

9. - E2C09

What type of equipment is commonly used to implement a ham radio mesh network?

SelectAnswer
AA standard wireless router running custom software
BA 2 meter VHF transceiver with a 1200 baud modem
CAn optical cable connection between the USB ports of 2 separate computers
DA 440 MHz transceiver with a 9600 baud modem

10. - E2D08

What type of packet frame is used to transmit APRS beacon data?

SelectAnswer
AConnect
BAcknowledgement
CDisconnect
DUnnumbered Information

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. - E3A13

Which emission mode is best for aurora propagation?

SelectAnswer
ASSB
BFM
CCW
DRTTY

13. - E3B02

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

SelectAnswer
A7500 miles
B5000 miles
C2500 miles
D1000 miles

14. - E3C06

By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

SelectAnswer
ABy approximately 50 percent of the distance
BBy approximately twice the distance
CBy approximately 15 percent of the distance
DBy approximately four times the distance

15. - E4A12

Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?

SelectAnswer
AAttenuate the transmitter output going to the spectrum analyzer
BMatch the antenna to the load
CUse high quality double shielded coaxial cables to reduce signal losses
DAll of these choices are correct

16. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

SelectAnswer
ATime base accuracy
BInput attenuator accuracy
CTemperature coefficient of the logic
DDecade divider accuracy

17. - E4C07

What does the MDS of a receiver represent?

SelectAnswer
AThe meter display sensitivity
BThe multiplex distortion stability
CThe minimum discernible signal
DThe maximum detectable spectrum

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
A146.34 MHz and 146.61 MHz
B146.10 MHz and 147.30 MHz
C146.88 MHz and 146.34 MHz
D173.35 MHz and 139.40 MHz

19. - E4E04

How can conducted and radiated noise caused by an automobile alternator be suppressed?

SelectAnswer
ABy installing a noise suppression resistor and a blocking capacitor in both leads
BBy installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead
CBy installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead
DBy connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads

20. - E5A17

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

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

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

SelectAnswer
A55 seconds
B440 seconds
C220 seconds
D110 seconds

22. - E5C07

What is a vector?

SelectAnswer
AA quantity with both magnitude and an angular component
BThe inverse of the sine function
CThe value of a quantity that changes over time
DThe inverse of the tangent function

23. - E5D18

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

SelectAnswer
A252 W
B704 W
C1.42 mW
D355 W

24. - E6A02

Which of the following semiconductor materials contains excess free electrons?

SelectAnswer
AInsulated gate
BBipolar
CN-type
DP-type

25. - E6B09

What is a common use for point contact diodes?

SelectAnswer
AAs an RF detector
BAs a high voltage rectifier
CAs a constant current source
DAs a constant voltage source

26. - E6C06

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

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

27. - E6D06

What core material property determines the inductance of a toroidal inductor?

SelectAnswer
APermeability
BThermal impedance
CResistance
DReactivity

28. - E6E10

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

SelectAnswer
ASurface mount
BStripped lead
CDirect soldering
DVirtual lead mounting

29. - E6F06

Which of these materials is affected the most by photoconductivity?

SelectAnswer
AA heavy metal
BA crystalline semiconductor
CA liquid semiconductor
DAn ordinary metal

30. - E7A10

What is a truth table?

SelectAnswer
AA table of logic symbols that indicate the logic states of an op-amp
BA list of inputs and corresponding outputs for a digital device
CA table of logic symbols that indicate the high logic states of an op-amp
DA diagram showing logic states when the digital device output is true

31. - E7B01

For what portion of a signal cycle does a Class AB amplifier operate?

SelectAnswer
AThe entire cycle
BMore than 180 degrees but less than 360 degrees
CLess than 180 degrees
DExactly 180 degrees

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
ALower losses
BGreater transformation range
CHigher efficiency
DGreater harmonic suppression

33. - E7D05

Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?

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

34. - E7E11

Which type of detector is used for demodulating SSB signals?

SelectAnswer
ADiscriminator
BPhase comparator
CProduct detector
DPhase detector

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

36. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

SelectAnswer
AIt increases linearly with increasing frequency
BIt does not vary with frequency
CIt decreases logarithmically with increasing frequency
DIt decreases linearly with increasing frequency

37. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

SelectAnswer
AA phase locked loop synthesizer
BA diode-switching matrix synthesizer
CA hybrid synthesizer
DA direct digital synthesizer

38. - E8A05

What would be the most accurate way of measuring the RMS voltage of a complex waveform?

SelectAnswer
ABy using a grid dip meter
BBy measuring the heating effect in a known resistor
CBy using an absorption wave meter
DBy measuring the voltage with a D'Arsonval meter

39. - E8B02

How does the modulation index of a phase-modulated emission vary with RF carrier frequency (the modulated frequency)?

SelectAnswer
AIt increases as the RF carrier frequency increases
BIt varies with the square root of the RF carrier frequency
CIt does not depend on the RF carrier frequency
DIt decreases as the RF carrier frequency increases

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

SelectAnswer
AGray code
BExcess 3 code
CExtended Binary Coded Decimal Interchange Code
DBinary Coded Decimal Code

41. - E8D10

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

SelectAnswer
ABaudot 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
BBaudot 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
CBaudot 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
DBaudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

42. - E9A02

What antenna has no gain in any direction?

SelectAnswer
AQuarter-wave vertical
BYagi
CIsotropic antenna
DHalf-wave dipole

43. - E9B07

How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from an isotropic antenna, assuming each is driven by the same amount of power?

SelectAnswer
AThe radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna
BThey are the same
CThe total amount of radiation from the directional antenna is increased by the gain of the antenna
DThe total amount of radiation from the directional antenna is stronger by its front-to-back ratio

44. - E9C02

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

SelectAnswer
ACardioid
BA figure-8 broadside to the axis of the array
CA figure-8 end-fire along the axis of the array
DOmni-directional

45. - E9D03

Where should a high Q loading coil be placed to minimize losses in a shortened vertical antenna?

SelectAnswer
ANear the center of the vertical radiator
BAs low as possible on the vertical radiator
CAs close to the transmitter as possible
DAt a voltage node

46. - E9E03

What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?

SelectAnswer
AThe delta match
BThe stub match
CThe gamma match
DThe omega match

47. - E9F13

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

SelectAnswer
AThe same as the characteristic impedance of the transmission line
BThe same as the generator output impedance
CVery low impedance
DVery high impedance

48. - E9G03

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

SelectAnswer
AImpedance and SWR values in transmission lines
BSatellite azimuth and elevation bearings
CTrigonometric functions
DBeam headings and radiation patterns

49. - E9H11

What characteristic of a cardioid pattern antenna is useful for direction finding?

SelectAnswer
ABroad band response
BHigh-radiation angle
CA very sharp peak
DA very sharp single null

50. - E0A05

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

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