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

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1. - E0A05

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

Select	Answer
A	Microwaves often travel long distances by ionospheric reflection
B	The high gain antennas commonly used can result in high exposure levels
C	The extremely high frequency energy can damage the joints of antenna structures
D	Microwaves are ionizing radiation

2. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

Select	Answer
A	At the center frequency of the channel
B	At the highest frequency of the channel
C	At the lowest frequency of the channel
D	On any frequency where the signal's sidebands are within the channel

3. - E1B01

Which of the following constitutes a spurious emission?

Select	Answer
A	An emission outside the signal's necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
B	Any transmitted signal that unintentionally interferes with another licensed radio station
C	An amateur station transmission made without the proper call sign identification
D	A signal transmitted to prevent its detection by any station other than the intended recipient

4. - E1C07

At what level below a signal's mean power level is its bandwidth determined according to FCC rules?

Select	Answer
A	6 dB
B	3 dB
C	23 dB
D	26 dB

5. - E1D02

Which of the following may transmit special codes intended to obscure the meaning of messages?

Select	Answer
A	Auxiliary relay links carrying repeater audio
B	Data containing personal information
C	Binary control characters
D	Telecommand signals from a space telecommand station

6. - E1E08

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

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

7. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

Select	Answer
A	To provide additional spectrum for personal use
B	To allow regular operation on Land Mobile channels
C	To provide temporary operation while awaiting normal licensing
D	To provide for experimental amateur communications

8. - E2A04

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

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

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

10. - E2C09

What type of equipment is commonly used to implement an amateur radio mesh network?

Select	Answer
A	A 2 meter VHF transceiver with a 1200 baud modem
B	A wireless router running custom firmware
C	A 440 MHz transceiver with a 9600 baud modem
D	An optical cable connection between the USB ports of 2 separate computers

11. - E2D09

What type of modulation is used for JT65 contacts?

Select	Answer
A	PSK
B	Multi-tone AFSK
C	IEEE 802.11
D	RTTY

12. - E2E08

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

Select	Answer
A	AMTOR
B	Hellschreiber
C	PACTOR
D	RTTY

13. - E3A02

What characterizes libration fading of an EME signal?

Select	Answer
A	A slow change in the pitch of the CW signal
B	A gradual loss of signal as the sun rises
C	The returning echo is several hertz lower in frequency than the transmitted signal
D	A fluttery irregular fading

14. - E3B04

What is meant by the terms "extraordinary" and "ordinary" waves?

Select	Answer
A	Independent waves created in the ionosphere that are elliptically polarized
B	Long-path and short-path waves
C	Refracted rays and reflected waves
D	Extraordinary waves describe rare long-skip propagation compared to ordinary waves, which travel shorter distances

15. - E3C13

What type of polarization is best for ground-wave propagation?

Select	Answer
A	Horizontal
B	Elliptical
C	Vertical
D	Circular

16. - E4A03

Which of the following test instruments is used to display spurious signals and/or intermodulation distortion products generated by an SSB transmitter?

Select	Answer
A	A wattmeter
B	A spectrum analyzer
C	A logic analyzer
D	A time-domain reflectometer

17. - E4B01

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

Select	Answer
A	Time base accuracy
B	Temperature coefficient of the logic
C	Decade divider accuracy
D	Input attenuator accuracy

18. - E4C09

Which of the following choices is a good reason for selecting a high frequency for the design of the IF in a superheterodyne HF or VHF communications receiver?

Select	Answer
A	Improved receiver noise figure
B	Fewer components in the receiver
C	Easier for front-end circuitry to eliminate image responses
D	Reduced drift

19. - E4D11

Why are odd-order intermodulation products, created within a receiver, of particular interest compared to other products?

Select	Answer
A	Odd-order products overload the IF filters
B	Odd-order intermodulation produces three products for every input signal within the band of interest
C	Odd-order products are an indication of poor image rejection
D	Odd-order products of two signals in the band of interest are also likely to be within the band

20. - E4E02

Which of the following types of noise can often be reduced with a digital signal processing noise filter?

Select	Answer
A	Broadband white noise
B	Ignition noise
C	Power line noise
D	All these choices are correct

21. - E5A01

What can cause the voltage across reactances in a series RLC circuit to be higher than the voltage applied to the entire circuit?

Select	Answer
A	Conductance
B	Capacitance
C	Resonance
D	Resistance

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

23. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

Select	Answer
A	A positive magnitude
B	A negative magnitude
C	A negative phase angle
D	A positive phase angle

24. - E5D01

What is the result of skin effect?

Select	Answer
A	As frequency decreases, RF current flows in a thinner layer of the conductor, closer to the surface
B	Thermal effects on the surface of the conductor decrease the impedance
C	Thermal effects on the surface of the conductor increase the impedance
D	As frequency increases, RF current flows in a thinner layer of the conductor, closer to the surface

25. - E6A10

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

Select	Answer
A	6
B	2
C	4
D	5

26. - E6B01

What is the most useful characteristic of a Zener diode?

Select	Answer
A	A constant current drop under conditions of varying voltage
B	An internal capacitance that varies with the applied voltage
C	A constant voltage drop under conditions of varying current
D	A negative resistance region

27. - E6C11

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

Select	Answer
A	4
B	6
C	5
D	2

28. - E6D04

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

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

29. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

Select	Answer
A	Plate current that is controlled by a control grid
B	Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range
C	Nearly infinite gain, very high input impedance, and very low output impedance
D	The ability to retrieve information from a single signal even in the presence of other strong signals

30. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

Select	Answer
A	Cadmium Sulfide
B	Selenium
C	Copper oxide
D	Silicon

31. - E7A01

Which circuit is bistable?

Select	Answer
A	An AND gate
B	An OR gate
C	A bipolar amplifier
D	A flip-flop

32. - E7B09

Which of the following describes how the loading and tuning capacitors are to be adjusted when tuning a vacuum tube RF power amplifier that employs a Pi-network output circuit?

Select	Answer
A	The tuning capacitor is set to maximum capacitance and the loading capacitor is adjusted for minimum plate permissible current
B	The loading capacitor is set to maximum capacitance and the tuning capacitor is adjusted for minimum allowable plate current
C	The loading capacitor is adjusted to minimum plate current while alternately adjusting the tuning capacitor for maximum allowable plate current
D	The tuning capacitor is adjusted for minimum plate current, and the loading capacitor is adjusted for maximum permissible plate current

33. - E7C04

How does an impedance-matching circuit transform a complex impedance to a resistive impedance?

Select	Answer
A	It introduces negative resistance to cancel the resistive part of impedance
B	Reactive currents are dissipated in matched resistances
C	It cancels the reactive part of the impedance and changes the resistive part to a desired value
D	It introduces transconductance to cancel the reactive part of impedance

34. - E7D02

What is a characteristic of a switching electronic voltage regulator?

Select	Answer
A	The resistance of a control element is varied in direct proportion to the line voltage or load current
B	It gives a ramp voltage at its output
C	The controlled device's duty cycle is changed to produce a constant average output voltage
D	It is generally less efficient than a linear regulator

35. - E7E01

Which of the following can be used to generate FM phone emissions?

Select	Answer
A	A balanced modulator on the oscillator
B	A balanced modulator on the audio amplifier
C	A reactance modulator on the final amplifier
D	A reactance modulator on the oscillator

36. - E7F05

How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?

Select	Answer
A	At least twice the rate of the highest frequency component of the signal
B	At the same rate as the highest frequency component of the signal
C	At four times the rate of the highest frequency component of the signal
D	At least half the rate of the highest frequency component of the signal

37. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 3300 ohms and RF is 47 kilohms?

Select	Answer
A	14
B	0.07
C	7
D	28

38. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

Select	Answer
A	Pierce and Zener
B	Negative feedback and balanced feedback
C	Armstrong and deForest
D	Colpitts and Hartley

39. - E8A07

What determines the PEP-to-average power ratio of a single-sideband phone signal?

Select	Answer
A	The degree of carrier suppression
B	Amplifier gain
C	The frequency of the modulating signal
D	Speech characteristics

40. - E8B10

What is frequency division multiplexing?

Select	Answer
A	The transmitted signal is divided into packets of information
B	Two or more information streams are merged into a baseband, which then modulates the transmitter
C	The transmitted signal jumps from band to band at a predetermined rate
D	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter

41. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	Baud is twice the symbol rate
B	Baud is only used for RTTY
C	Symbol rate is only used for packet-based modes
D	They are the same

42. - E8D08

What parameter evaluates distortion of an AFSK signal caused by excessive input audio levels?

Select	Answer
A	Baud rate
B	Intermodulation Distortion (IMD)
C	Signal-to-noise ratio
D	Repeat Request Rate (RRR)

43. - E9A10

Which of the following improves the efficiency of a ground-mounted quarter-wave vertical antenna?

Select	Answer
A	All these choices are correct
B	Isolating the coax shield from ground
C	Installing a radial system
D	Shortening the radiating element

44. - E9B02

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?

Select	Answer
A	24 dB
B	36 dB
C	18 dB
D	14 dB

45. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus soil?

Select	Answer
A	The low-angle radiation increases
B	Additional higher vertical angle lobes will appear
C	The low-angle radiation decreases
D	Fewer vertical angle lobes will be present

46. - E9D05

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

Select	Answer
A	The SWR is reduced
B	The front-to-back ratio decreases
C	The front-to-back ratio increases
D	The frequency response is widened over the whole frequency band

47. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

Select	Answer
A	The delta match
B	The stub match
C	The epsilon match
D	The gamma match

48. - E9F03

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

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

49. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The current axis
B	The reactance axis
C	The voltage axis
D	The resistance axis

50. - E9H03

What is Receiving Directivity Factor (RDF)?

Select	Answer
A	Forward gain compared to average gain over the entire hemisphere
B	Relative directivity compared to isotropic
C	Forward gain compared to the gain in the reverse direction
D	Relative directivity compared to a dipole

Figure E6-1

Figure E6-3

Figure E7-3

Figure E9-1

Figure E9-3