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

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1. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Mica
B	Beryllium Oxide
C	Zinc oxide
D	Uranium Hexafluoride

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

3. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

Select	Answer
A	You must obtain a construction permit from the airport zoning authority
B	You must file an Environmental Impact Statement with the EPA before construction begins
C	You must submit engineering drawings to the FAA
D	You may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of the FCC rules

4. - E1C02

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

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

5. - E1D09

Which UHF amateur bands have frequencies authorized for space stations?

Select	Answer
A	70 cm and 33 cm
B	70 cm only
C	70 cm and 13 cm
D	33 cm and 13 cm

6. - E1E08

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

Select	Answer
A	Relatives of the VE as listed in the FCC rules
B	Friends of the VE
C	Employees of the VE
D	All these choices are correct

7. - E1F07

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

Select	Answer
A	When transmitting international third-party communications
B	When the total money involved does not exceed $25
C	When neither the amateur nor his or her employer has a pecuniary interest in the communications
D	When the control operator is employed by the FCC or another government agency

8. - E2A08

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

Select	Answer
A	To avoid interfering with terrestrial QSOs
B	To prevent the satellite from emitting out-of-band signals
C	To avoid reducing the downlink power to all other users
D	To prevent creating errors in the satellite telemetry

9. - E2B08

What technique allows commercial analog TV receivers to be used for fast-scan TV operations on the 70 cm band?

Select	Answer
A	Using USB and demodulating the signal with a computer sound card
B	Transmitting on channels shared with cable TV
C	Using converted satellite TV dishes
D	Transmitting on the abandoned TV channel 2

10. - E2C02

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

Select	Answer
A	An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
B	A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
C	The acceptable practice of manually posting the call signs of stations on a spotting network
D	The often-prohibited practice of posting one's own call sign and frequency on a spotting network

11. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
B	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
C	An APRS station with a Global Positioning System unit can automatically transmit information to show a mobile station's position during the event
D	All these choices are correct

12. - E2E08

Which of the following HF digital modes can be used to transfer binary files?

Select	Answer
A	PACTOR
B	AMTOR
C	Hellschreiber
D	RTTY

13. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

Select	Answer
A	Temperature inversion
B	Dust devil
C	Wind shear
D	The jet stream

14. - E3B12

What is the primary characteristic of chordal hop propagation?

Select	Answer
A	Successive ionospheric refractions without an intermediate reflection from the ground
B	Propagation across the geomagnetic equator
C	Signals reflected back toward the transmitting station
D	Propagation away from the great circle bearing between stations

15. - E3C11

What does VOACAP software model?

Select	Answer
A	AC current and impedance
B	VHF radio propagation
C	AC voltage and impedance
D	HF propagation

16. - E4A08

Which of the following measures SWR?

Select	Answer
A	An antenna analyzer
B	A spectrum analyzer
C	A Q meter
D	An ohmmeter

17. - E4B07

What do the subscripts of S parameters represent?

Select	Answer
A	The port or ports at which measurements are made
B	Relative quality of the data
C	Frequency order of the measurements
D	The relative time between measurements

18. - E4C07

What does the MDS of a receiver represent?

Select	Answer
A	The maximum detectable spectrum
B	The meter display sensitivity
C	The minimum discernible signal
D	The multiplex distortion stability

19. - E4D02

Which of the following describes problems caused by poor dynamic range in a receiver?

Select	Answer
A	Cross-modulation of the desired signal and insufficient audio power to operate the speaker
B	Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
C	Spurious signals caused by cross-modulation and desensitization from strong adjacent signals
D	Oscillator instability and severe audio distortion of all but the strongest received signals

20. - E4E03

Which of the following signals might a receiver noise blanker be able to remove from desired signals?

Select	Answer
A	Signals that appear across a wide bandwidth
B	Signals that appear at one IF but not another
C	Signals that have a sharply peaked frequency distribution
D	Signals that are constant at all IF levels

21. - E5A02

What is resonance in an LC or RLC circuit?

Select	Answer
A	The frequency at which the capacitive reactance equals the inductive reactance
B	The lowest frequency that will pass current
C	The frequency at which the reactive impedance equals the resistive impedance
D	The highest frequency that will pass current

22. - E5B07

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

Select	Answer
A	14.0 degrees with the voltage leading the current
B	14.0 degrees with the voltage lagging the current
C	68.2 degrees with the voltage leading the current
D	68.2 degrees with the voltage lagging the current

23. - E5C12

Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and a 19-picofarad capacitor at 21.200 MHz?

Select	Answer
A	Point 3
B	Point 7
C	Point 8
D	Point 1

24. - E5D11

What is the power factor of an RL circuit having a 60-degree phase angle between the voltage and the current?

Select	Answer
A	0.866
B	0.5
C	1.414
D	1.73

25. - E6A10

In Figure E6-1, what is the schematic symbol for an N-channel dual-gate MOSFET?

Select	Answer
A	4
B	5
C	6
D	2

26. - E6B10

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

Select	Answer
A	6
B	5
C	1
D	7

27. - E6C04

Which of the following is an advantage of BiCMOS logic?

Select	Answer
A	Its simplicity results in much less expensive devices than standard CMOS
B	It has the high input impedance of CMOS and the low output impedance of bipolar transistors
C	It is immune to electrostatic damage
D	All these choices are correct

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. - E6E07

What type of transmission line is used for connections to MMICs?

Select	Answer
A	Parallel wire
B	Miniature coax
C	Circular waveguide
D	Microstrip

30. - E6F11

What is the approximate open-circuit voltage produced by a fully illuminated silicon photovoltaic cell?

Select	Answer
A	1.5 V
B	0.1 V
C	12 V
D	0.5 V

31. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

Select	Answer
A	A flip-flop
B	An OR gate
C	A multiplexer
D	An XOR gate

32. - E7B08

How can an RF power amplifier be neutralized?

Select	Answer
A	By increasing the driving power
B	By feeding an in-phase component of the output back to the input
C	By feeding a 180-degree out-of-phase portion of the output back to the input
D	By reducing the driving power

33. - E7C01

How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network's input and output?

Select	Answer
A	Two capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
B	An inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output
C	A capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between input and output
D	Two inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground

34. - E7D01

How does a linear electronic voltage regulator work?

Select	Answer
A	It eliminates the need for a pass transistor
B	The control element duty cycle is proportional to the line or load conditions
C	It has a ramp voltage as its output
D	The conduction of a control element is varied to maintain a constant output voltage

35. - E7E04

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

Select	Answer
A	By using a reactance modulator followed by a mixer
B	By driving a product detector with a DSB signal
C	By using a balanced modulator followed by a filter
D	By using a loop modulator followed by a mixer

36. - E7F12

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters are easier to implement for a given set of passband rolloff requirements
B	FIR filters can respond faster to impulses
C	All these choices are correct
D	FIR filters can delay all frequency components of the signal by the same amount

37. - E7G06

What is the gain-bandwidth of an operational amplifier?

Select	Answer
A	The gain of the amplifier at a filter's cutoff frequency
B	The frequency at which the amplifier's offset voltage is zero
C	The frequency at which the open-loop gain of the amplifier equals one
D	The maximum frequency for a filter circuit using that type of amplifier

38. - E7H01

What are three oscillator circuits used in amateur radio equipment?

Select	Answer
A	Taft, Hartley and Pierce
B	Taft, Pierce and negative feedback
C	Colpitts, Hartley and Pierce
D	Pierce, Fenner and Beane

39. - E8A03

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

Select	Answer
A	A square wave
B	A sawtooth wave
C	A cosine wave
D	A sine wave

40. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

Select	Answer
A	3000
B	3
C	1000
D	0.3

41. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By varying the frequency shift of the transmitted signal according to a predefined algorithm
B	By transmitting extra data that may be used to detect and correct transmission errors
C	By the receiving station repeating each block of three data characters
D	By transmitting a special algorithm to the receiving station along with the data characters

42. - E8D05

What is the most common method of reducing key clicks?

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

43. - E9A08

What is antenna bandwidth?

Select	Answer
A	The angle between the half-power radiation points
B	The angle formed between two imaginary lines drawn through the element ends
C	The frequency range over which an antenna satisfies a performance requirement
D	Antenna length divided by the number of elements

44. - E9B06

What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	45 degrees
B	25 degrees
C	75 degrees
D	7.5 degrees

45. - E9C08

What is a folded dipole antenna?

Select	Answer
A	A dipole one-quarter wavelength long
B	A type of ground-plane antenna
C	A dipole configured to provide forward gain
D	A half-wave dipole with an additional parallel wire connecting its two ends

46. - E9D04

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

Select	Answer
A	To swamp out harmonics
B	To minimize losses
C	To minimize the Q
D	To lower the radiation angle

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 gamma matching system
B	The omega matching system
C	The stub matching system
D	The delta matching system

48. - E9F11

What impedance does a 1/8-wavelength transmission line present to a generator when the line is open at the far end?

Select	Answer
A	An inductive reactance
B	A capacitive reactance
C	The same as the characteristic impedance of the line
D	Infinite

49. - E9G02

What type of coordinate system is used in a Smith chart?

Select	Answer
A	Resistance circles and reactance arcs
B	Voltage lines and current chords
C	Resistance lines and reactance chords
D	Voltage circles and current arcs

50. - E9H08

What is the function of a sense antenna?

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

Figure E5-1

Figure E6-1

Figure E6-2

Figure E9-2