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

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1. - E0A01

What is the primary function of an external earth connection or ground rod?

Select	Answer
A	Reduce received noise
B	Reduce RF current flow between pieces of equipment
C	Lightning protection
D	Reduce RFI to telephones and home entertainment systems

2. - E1A13

Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?

Select	Answer
A	Any person holding an FCC issued amateur license or who is authorized for alien reciprocal operation
B	Any person named in an amateur station license grant or a person holding an unrestricted Radiotelephone Operator Permit
C	Only a person with an FCC Marine Radio license grant
D	Only a person named in an amateur station license grant

3. - E1B10

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

Select	Answer
A	Specific segments in the amateur service MF, HF, VHF and UHF bands
B	All amateur service frequencies authorized to the control operator
C	Specific local government channels
D	Military Auxiliary Radio System (MARS) channels

4. - E1C02

Which of the following types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	Business-related messages for non-profit organizations
B	All these choices are correct
C	Communications incidental to the purpose of the amateur service and remarks of a personal nature
D	Messages intended for users of the maritime satellite service

5. - E1D03

What is a space telecommand station?

Select	Answer
A	An amateur station that transmits communications to initiate, modify or terminate functions of a space station
B	An amateur station located on the surface of the Earth for communication with other Earth stations by means of Earth satellites
C	An amateur station that receives telemetry from a satellite or balloon more than 50 kilometers above the surface of the Earth
D	An amateur station located in a satellite or a balloon more than 50 kilometers above the surface of the Earth

6. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

Select	Answer
A	Destroy the application form
B	Maintain the application form with the VEC's records
C	Return the application document to the examinee
D	Send the application form to the FCC and inform the FCC of the grade

7. - 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?

Select	Answer
A	222 MHz - 223 MHz
B	440 MHz - 450 MHz
C	53 MHz - 54 MHz
D	420 MHz - 430 MHz

8. - E2A04

What is meant by the term mode? as applied to an amateur radio satellite?

Select	Answer
A	Whether the satellite is in a low earth or geostationary orbit
B	The satellite's uplink and downlink frequency bands
C	The satellite's orientation with respect to the Earth
D	Whether the satellite is in a polar or equatorial orbit

9. - E2B01

How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?

Select	Answer
A	30
B	60
C	90
D	120

10. - E2C04

Which of the following frequencies are sometimes used for amateur radio mesh networks?

Select	Answer
A	HF frequencies where digital communications are permitted
B	Frequencies shared with various unlicensed wireless data services
C	The 60 meter band channel centered on 5373 kHz
D	Cable TV channels 41 through 43

11. - E2D08

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

Select	Answer
A	Unnumbered Information
B	Connect
C	Acknowledgement
D	Disconnect

12. - E2E03

How is the timing of FT4 contacts organized?

Select	Answer
A	By exchanging ACK/NAK packets
B	Alternating transmissions at 7.5 second intervals
C	It depends on the lunar phase
D	Stations take turns on alternate days

13. - E3A08

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

Select	Answer
A	The F1 layer
B	The D layer
C	The F2 layer
D	The E layer

14. - E3B06

Which of the following amateur bands most frequently provides long-path propagation?

Select	Answer
A	80 meters
B	6 meters
C	20 meters
D	10 meters

15. - E3C08

What does the space weather term G5 mean?

Select	Answer
A	An extreme geomagnetic storm
B	Waning sunspot numbers
C	Very low solar activity
D	Moderate solar wind

16. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Network analyzer
B	Modulation monitor
C	Logic analyzer
D	Bit error rate tester

17. - E4B04

Which S parameter represents input port return loss or reflection coefficient (equivalent to VSWR)?

Select	Answer
A	S11
B	S12
C	S22
D	S21

18. - E4C14

What transmit frequency might generate an image response signal in a receiver tuned to 14.300 MHz and that uses a 455 kHz IF frequency?

Select	Answer
A	14.755 MHz
B	14.445 MHz
C	15.210 MHz
D	13.845 MHz

19. - E4D03

How can intermodulation interference between two repeaters occur?

Select	Answer
A	When the signals from the transmitters are reflected out of phase from airplanes passing overhead
B	When the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters
C	When the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters
D	When the signals from the transmitters are reflected in phase from airplanes passing overhead

20. - E4E05

How can radio frequency interference from an AC motor be suppressed?

Select	Answer
A	By installing a brute-force AC-line filter in series with the motor leads
B	By installing a high-pass filter in series with the motor's power leads
C	By using a ground-fault current interrupter in the circuit used to power the motor
D	By installing a bypass capacitor in series with the motor leads

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?

Select	Answer
A	22.36 MHz
B	44.72 MHz
C	3.56 MHz
D	1.78 MHz

22. - E5B09

What is the relationship between the AC current through a capacitor and the voltage across a capacitor?

Select	Answer
A	Voltage and current are in phase
B	Voltage and current are 180 degrees out of phase
C	Current leads voltage by 90 degrees
D	Voltage leads current by 90 degrees

23. - E5C08

What coordinate system is often used to display the phase angle of a circuit containing resistance, inductive and/or capacitive reactance?

Select	Answer
A	Maidenhead grid
B	Polar coordinates
C	Elliptical coordinates
D	Faraday grid

24. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

Select	Answer
A	It is dissipated as kinetic energy in the circuit
B	It is dissipated in the formation of inductive and capacitive fields
C	It is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
D	It is dissipated as heat in the circuit

25. - E6A11

In Figure E6-1, what is the schematic symbol for a P-channel junction FET?

Select	Answer
A	3
B	1
C	6
D	2

26. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

Select	Answer
A	Much higher reverse voltage breakdown
B	Longer carrier retention time
C	More constant reverse avalanche voltage
D	Less forward voltage drop

27. - E6C08

In Figure E6-3, what is the schematic symbol for a NAND gate?

Select	Answer
A	3
B	2
C	1
D	4

28. - E6D04

Which materials are commonly used as a core in an inductor?

Select	Answer
A	Teflon and Delrin
B	Polystyrene and polyethylene
C	Cobalt and aluminum
D	Ferrite and brass

29. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

Select	Answer
A	300 ohms
B	450 ohms
C	10 ohms
D	50 ohms

30. - E6F01

What absorbs the energy from light falling on a photovoltaic cell?

Select	Answer
A	Holes
B	Protons
C	Electrons
D	Photons

31. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It produces a continuous square wave oscillating between 1 and 0
B	It stores one bit of data in either a 0 or 1 state
C	It switches momentarily to the opposite binary state and then returns to its original state after a set time
D	It maintains a constant output voltage, regardless of variations in the input voltage

32. - E7B10

In Figure E7-1, what is the purpose of R1 and R2?

Select	Answer
A	Load resistors
B	Voltage divider bias
C	Self bias
D	Feedback

33. - E7C06

What are the distinguishing features of an elliptical filter?

Select	Answer
A	Gradual passband rolloff with extreme stop band ripple
B	Gradual passband rolloff with minimal stop band ripple
C	Extremely sharp cutoff with one or more notches in the stop band
D	Extremely flat response over its pass band with gradually rounded stop band corners

34. - E7D05

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

Select	Answer
A	A shunt regulator
B	A constant current source
C	A shunt current source
D	A series regulator

35. - E7E06

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

Select	Answer
A	To remove third-order distortion products
B	For higher efficiency
C	For compatibility with transmitters using phase modulation
D	To reduce impulse noise reception

36. - E7F11

What sets the minimum detectable signal level for a direct-sampling SDR receiver in the absence of atmospheric or thermal noise?

Select	Answer
A	Reference voltage level and sample width in bits
B	Sample clock phase noise
C	Missing codes and jitter
D	Data storage transfer rate

37. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E73 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	94
B	24
C	47
D	0.21

38. - E7H05

How is positive feedback supplied in a Pierce oscillator?

Select	Answer
A	Through a tapped coil
B	Through a quartz crystal
C	Through link coupling
D	Through a neutralizing capacitor

39. - E8A05

What of the following instruments would be the most accurate for measuring the RMS voltage of a complex waveform?

Select	Answer
A	An absorption wave meter
B	A grid dip meter
C	A true-RMS calculating meter
D	A D'Arsonval meter

40. - E8B02

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

Select	Answer
A	It varies with the square root of the RF carrier frequency
B	It does not depend on the RF carrier frequency
C	It decreases as the RF carrier frequency increases
D	It increases as the RF carrier frequency increases

41. - E8C10

How may data rate be increased without increasing bandwidth?

Select	Answer
A	Increasing analog-to-digital conversion resolution
B	Using a more efficient digital code
C	It is impossible
D	Using forward error correction

42. - E8D05

What is the most common method of reducing key clicks?

Select	Answer
A	High-pass filters at the transmitter output
B	Low-pass filters at the transmitter output
C	Reduce keying waveform rise and fall times
D	Increase keying waveform rise and fall times

43. - E9A12

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 6 dB gain over an isotropic antenna?

Select	Answer
A	2.79 dB
B	3.85 dB
C	6.0 dB
D	8.15 dB

44. - E9B11

What is a disadvantage of decreasing the number of wire segments in an antenna model below 10 segments per half-wavelength?

Select	Answer
A	The antenna will become mechanically unstable
B	The resulting design will favor radiation of harmonic energy
C	Ground conductivity will not be accurately modeled
D	The computed feed point impedance may be incorrect

45. - E9C06

What is the effect of adding a terminating resistor to a rhombic antenna?

Select	Answer
A	It changes the radiation pattern from horizontal to vertical polarization
B	It changes the radiation pattern from bidirectional to unidirectional
C	It reflects the standing waves on the antenna elements back to the transmitter
D	It decreases the ground loss

46. - E9D11

Which of the following conductors would be best for minimizing losses in a station's RF ground system?

Select	Answer
A	Wide flat copper strap
B	Stranded wire
C	Solid wire
D	Resistive wire, such as spark plug wire

47. - E9E01

What system matches a higher-impedance transmission line to a lower-impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

Select	Answer
A	The omega matching system
B	The stub matching system
C	The delta matching system
D	The gamma matching system

48. - E9F03

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

Select	Answer
A	Electrical signals move more slowly in a coaxial cable than in air
B	The characteristic impedance is higher in a parallel feed line
C	The surge impedance is higher in a parallel feed line
D	Skin effect is less pronounced in the coaxial cable

49. - E9G09

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

Select	Answer
A	Radiation-pattern circles
B	Coaxial-length circles
C	Antenna-length circles
D	Standing wave ratio circles

50. - E9H08

What is the function of a sense antenna?

Select	Answer
A	It provides diversity reception that cancels multipath signals
B	It modifies the pattern of a DF antenna array to provide a null in one direction
C	It allows DF antennas to receive signals at different vertical angles
D	It increases the sensitivity of a DF antenna array

Figure E6-1

Figure E6-3

Figure E7-1