Anonymous User

Hamboozler

US Amateur Radio - Amateur Extra (Element 4, 2020-2024) Practice Test

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E0A05

What is one of the potential hazards of operating in the amateur radio microwave bands?

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

2. - E1A12

What special operating frequency restrictions are imposed on slow scan TV transmissions?

SelectAnswer
AThey are not permitted above 54 MHz
BThey are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
CNone; they are allowed on all amateur frequencies
DThey are restricted to phone band segments

3. - E1B02

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
A10 kHz
B15 kHz
C3 kHz
D20 kHz

4. - E1C13

What notifications must be given before transmitting on the 630 meter or 2200 meter bands?

SelectAnswer
AA special endorsement must be requested from the FCC
BOperators must inform the FAA of their intent to operate, giving their call sign and distance to the nearest runway
COperators must inform the Utilities Technology Council (UTC) of their call sign and coordinates of the station
DAn environmental impact statement must be filed with the Department of the Interior

5. - E1D06

What is the maximum permitted transmitter output power when operating a model craft by telecommand?

SelectAnswer
A1 watt
B5 watts
C100 watts
D2 watts

6. - E1E08

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

SelectAnswer
AEmployees of the VE
BAll these choices are correct
CFriends of the VE
DRelatives of the VE as listed in the FCC rules

7. - E1F02

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

SelectAnswer
AAll privileges of the Amateur Extra Class license
BFull privileges, up to and including those of the Amateur Extra Class license, on the 80, 40, 20, 15, and 10 meter bands
CNone, they must obtain a U.S. license
DThe operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Amateur Extra Class license privileges

8. - E2A08

Why should effective radiated power to a satellite that uses a linear transponder be limited?

SelectAnswer
ATo prevent creating errors in the satellite telemetry
BTo avoid interfering with terrestrial QSOs
CTo prevent the satellite from emitting out-of-band signals
DTo avoid reducing the downlink power to all other users

9. - E2B10

What aspect of an analog slow-scan television signal encodes the brightness of the picture?

SelectAnswer
ASync amplitude
BTone amplitude
CSync frequency
DTone frequency

10. - E2C02

Which of the following best describes the term self-spotting? in connection with HF contest operating?

SelectAnswer
AA manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
BThe acceptable practice of manually posting the call signs of stations on a spotting network
CThe often-prohibited practice of posting one's own call sign and frequency on a spotting network
DAn automatic method for rapidly zero beating or tuning to a station's frequency before calling that station

11. - E2D04

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

SelectAnswer
AAPRS
BUltrasonics
CDoppler shift of beacon signals
DBandwidth compressed LORAN

12. - E2E10

Which of these digital modes has the narrowest bandwidth?

SelectAnswer
A170 Hz shift, 45-baud RTTY
B300-baud packet
CMFSK16
DPSK31

13. - E3A08

When a meteor strikes the Earth's atmosphere, a cylindrical region of free electrons is formed at what layer of the ionosphere?

SelectAnswer
AThe F1 layer
BThe E layer
CThe D layer
DThe F2 layer

14. - E3B12

What is the primary characteristic of chordal hop propagation?

SelectAnswer
APropagation away from the great circle bearing between stations
BSignals reflected back toward the transmitting station
CPropagation across the geomagnetic equator
DSuccessive ionospheric refractions without an intermediate reflection from the ground

15. - E3C06

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

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

16. - E4A08

Which of the following measures SWR?

SelectAnswer
AA Q meter
BAn antenna analyzer
CA spectrum analyzer
DAn ohmmeter

17. - E4B03

Which S parameter is equivalent to forward gain?

SelectAnswer
AS12
BS11
CS21
DS22

18. - E4C03

What is the term for the suppression in an FM receiver of one signal by another stronger signal on the same frequency?

SelectAnswer
ACapture effect
BCross-modulation interference
CFrequency discrimination
DDesensitization

19. - E4D07

Which of the following reduces the likelihood of receiver desensitization?

SelectAnswer
ASwitch from fast AGC to slow AGC
BDecrease the RF bandwidth of the receiver
CRaise the receiver IF frequency
DIncrease the receiver front end gain

20. - E4E10

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

SelectAnswer
AArcing contacts in a thermostatically controlled device
BA defective doorbell or doorbell transformer inside a nearby residence
CA malfunctioning illuminated advertising display
DAll these choices are correct

21. - E5A14

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

SelectAnswer
A1.78 MHz
B22.36 MHz
C3.56 MHz
D44.72 MHz

22. - E5B01

What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the applied voltage or to discharge to 36.8% of its initial voltage?

SelectAnswer
AAn exponential rate of one
BOne exponential period
CA time factor of one
DOne time constant

23. - E5C01

Which of the following represents capacitive reactance in rectangular notation?

SelectAnswer
A+jX
BOmega
C-jX
DDelta

24. - E5D10

How can the true power be determined in an AC circuit where the voltage and current are out of phase?

SelectAnswer
ABy dividing the reactive power by the power factor
BBy multiplying the reactive power by the power factor
CBy multiplying the apparent power by the power factor
DBy dividing the apparent power by the power factor

25. - 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 rejection frequency
DAlpha cutoff frequency

26. - E6B10

In Figure E6-2, what is the schematic symbol for a light-emitting diode?

SelectAnswer
A7
B6
C5
D1

27. - E6C11

In Figure E6-3, what is the schematic symbol for the NOT operation (inverter)?

SelectAnswer
A4
B5
C6
D2

28. - E6D02

What is the equivalent circuit of a quartz crystal?

SelectAnswer
AMotional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitor representing electrode and stray capacitance
BMotional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in series
CMotional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel
DMotional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance

29. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

SelectAnswer
ASilicon nitride
BSilicon dioxide
CSilicon
DGallium nitride

30. - E6F06

Which of these materials is most commonly used to create photoconductive devices?

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

31. - E7A10

What is a truth table?

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

32. - E7B17

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

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

33. - E7C09

What is a crystal lattice filter?

SelectAnswer
AA filter with narrow bandwidth and steep skirts made using quartz crystals
BA power supply filter made with interlaced quartz crystals
CAn audio filter made with four quartz crystals that resonate at 1 kHz intervals
DA filter using lattice-shaped quartz crystals for high-Q performance

34. - E7D12

What is the dropout voltage of an analog voltage regulator?

SelectAnswer
AMinimum input voltage for rated power dissipation
BMaximum that the output voltage may decrease at rated load
CMinimum input-to-output voltage required to maintain regulation
DMaximum output voltage drops when the input voltage is varied over its specified range

35. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

SelectAnswer
ATo remove third-order distortion products
BFor compatibility with transmitters using phase modulation
CFor higher efficiency
DTo reduce impulse noise reception

36. - E7F08

What is the function of decimation?

SelectAnswer
AReducing the effective sample rate by removing samples
BRemoving unnecessary significant digits
CConverting data to binary code decimal form
DAttenuating the signal

37. - E7G05

How can unwanted ringing and audio instability be prevented in an op-amp RC audio filter circuit?

SelectAnswer
ARestrict Q but increase gain
BIncrease both gain and Q
CRestrict gain but increase Q
DRestrict both gain and Q

38. - E7H05

How is positive feedback supplied in a Pierce oscillator?

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

39. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

SelectAnswer
AImmunity to out-of-sequence coding reduces spurious responses
BVery high speed allows digitizing high frequencies
CVery low power consumption decreases frequency drift
DAll these choices are correct

40. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

SelectAnswer
A47
B0.47
C0.214
D2.14

41. - E8C07

What is the bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

SelectAnswer
A15.36 kHz
B9.6 kHz
C4.8 kHz
D5.76 kHz

42. - E8D10

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

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

43. - E9A11

Which of the following factors determines ground losses for a ground-mounted vertical antenna operating in the 3 MHz to 30 MHz range?

SelectAnswer
ASoil conductivity
BTake-off angle
CDistance from the transmitter
DThe standing wave ratio

44. - E9B08

What is the far field of an antenna?

SelectAnswer
AThe region of the ionosphere where radiated power is not refracted
BThe region where the shape of the antenna pattern is independent of distance
CThe region where radiated power dissipates over a specified time period
DThe region where radiated field strengths are constant

45. - E9C03

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

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

46. - E9D03

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

SelectAnswer
AAt a voltage node
BNear the center of the vertical radiator
CAs close to the transmitter as possible
DAs low as possible on the vertical radiator

47. - E9E09

Which of the following is used to shunt-feed a grounded tower at its base?

SelectAnswer
AAll these choices are correct
BGamma match
CHairpin match
DDouble-bazooka match

48. - E9F12

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

SelectAnswer
AVery high impedance
BThe same as the input impedance to the generator
CThe same as the characteristic impedance of the line
DVery low impedance

49. - E9G03

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

SelectAnswer
ASatellite azimuth and elevation bearings
BTrigonometric functions
CBeam headings and radiation patterns
DImpedance and SWR values in transmission lines

50. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

SelectAnswer
AIt should be one or more wavelengths long
BIts overall length must not exceed 1/4 wavelength
CIt should be configured as a four-sided loop
DIt must be mounted more than 1 wavelength above ground

Figure E6-2

Figure E6-3