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

2. - E1A02

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

Select	Answer
A	300 Hz above the lower band edge
B	1 kHz above the lower band edge
C	3 kHz above the lower band edge
D	The exact lower band edge

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

4. - E1C08

What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?

Select	Answer
A	5 minutes
B	10 minutes
C	30 seconds
D	3 minutes

5. - E1D09

Which UHF amateur bands have frequencies authorized for space stations?

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

6. - E1E01

For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

Select	Answer
A	Preparing, processing, administering, and coordinating an examination for an amateur radio operator license
B	Providing amateur operator license examination preparation training materials
C	Teaching an amateur operator license examination preparation course
D	No expenses are authorized for reimbursement

7. - E1F04

Which of the following geographic descriptions approximately describes "Line A"?

Select	Answer
A	A line roughly parallel to and south of the border between the U.S. and Canada
B	A line roughly parallel to and north of the border between the U.S. and Mexico
C	A line roughly parallel to and west of the U.S. Atlantic coastline
D	A line roughly parallel to and east of the U.S. Pacific coastline

8. - E2A12

What is the purpose of digital store-and-forward functions on an amateur radio satellite?

Select	Answer
A	To upload operational software for the transponder
B	To store digital messages in the satellite for later download by other stations
C	To delay download of telemetry between satellites
D	To relay messages between satellites

9. - E2B01

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

Select	Answer
A	60
B	30
C	90
D	120

10. - E2C07

What is the Cabrillo format?

Select	Answer
A	The most common set of contest rules
B	A standard for submission of electronic contest logs
C	The rules of order for meetings between contest sponsors
D	A method of exchanging information during a contest QSO

11. - E2D03

Which of the following digital modes is especially useful for EME communications?

Select	Answer
A	PACTOR III
B	Olivia
C	MSK144
D	JT65

12. - E2E04

What is indicated when one of the ellipses in an FSK crossed-ellipse display suddenly disappears?

Select	Answer
A	One of the signal filters is saturated
B	The mark and space signal have been inverted
C	The receiver has drifted 5 kHz from the desired receive frequency
D	Selective fading has occurred

13. - E3A12

What is the cause of auroral activity?

Select	Answer
A	The interaction in the F2 layer between the solar wind and the Van Allen belt
B	An extreme low-pressure area in the polar regions
C	Meteor showers concentrated in the extreme northern and southern latitudes
D	The interaction in the E layer of charged particles from the Sun with the Earth's magnetic field

14. - E3B07

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

Select	Answer
A	They become phase locked
B	They are bent toward the magnetic poles
C	They become elliptically polarized
D	They become depolarized

15. - E3C08

What does the space weather term G5 mean?

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

16. - E4A09

Which of the following is good practice when using an oscilloscope probe?

Select	Answer
A	All these choices are correct
B	Never use a high-impedance probe to measure a low-impedance circuit
C	Never use a DC-coupled probe to measure an AC circuit
D	Keep the signal ground connection of the probe as short as possible

17. - E4B10

Which of the following methods measures intermodulation distortion in an SSB transmitter?

Select	Answer
A	Modulate the transmitter using two RF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer
B	Modulate the transmitter using two RF signals having harmonically related frequencies and observe the RF output with a logic analyzer
C	Modulate the transmitter using two AF signals having harmonically related frequencies and observe the RF output with a peak reading wattmeter
D	Modulate the transmitter using two AF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer

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

19. - E4D06

What is the term for spurious signals generated by the combination of two or more signals in a non-linear device or circuit?

Select	Answer
A	Intermodulation
B	Amplifier desensitization
C	Neutralization
D	Adjacent channel interference

20. - E4E07

Which of the following can cause shielded cables to radiate or receive interference?

Select	Answer
A	Common-mode currents on the shield and conductors
B	Use of braided shielding material
C	Tying all ground connections to a common point resulting in differential-mode currents in the shield
D	Low inductance ground connections at both ends of the shield

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	Capacitance
B	Resonance
C	Resistance
D	Conductance

22. - E5B02

What letter is commonly used to represent susceptance?

Select	Answer
A	Y
B	G
C	X
D	B

23. - E5C10

Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 400-ohm resistor and a 38-picofarad capacitor at 14 MHz?

Select	Answer
A	Point 4
B	Point 2
C	Point 5
D	Point 6

24. - E5D15

What is the power factor of an RL circuit having a 45-degree phase angle between the voltage and the current?

Select	Answer
A	0.707
B	0.866
C	1.0
D	0.5

25. - E6A11

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

Select	Answer
A	6
B	1
C	2
D	3

26. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch?

Select	Answer
A	Reverse bias controls its forward voltage drop
B	Ability to dissipate large amounts of power
C	Extremely high reverse breakdown voltage
D	Low junction capacitance

27. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	Programmable equipment used for testing digital logic integrated circuits
B	A type of transistor whose gain can be changed by digital logic circuits
C	A logic circuit that can be modified during use
D	A programmable collection of logic gates and circuits in a single integrated circuit

28. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores confine most of the magnetic field within the core material
B	Toroidal cores make it easier to couple the magnetic energy into other components
C	Toroidal cores have lower Q characteristics
D	Toroidal cores exhibit greater hysteresis

29. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

Select	Answer
A	Two chips in each package (Dual In Package)
B	Low leakage doubly insulated package
C	A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
D	Package mounts in a direct inverted position

30. - E6F05

Which describes an optical shaft encoder?

Select	Answer
A	A digital encryption device often used to encrypt spacecraft control signals
B	A device that measures the strength of a beam of light using analog to digital conversion
C	A device for generating RTTY signals by means of a rotating light source
D	A device that detects rotation of a control by interrupting a light source with a patterned wheel

31. - E7A01

Which circuit is bistable?

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

32. - E7B02

What is a Class D amplifier?

Select	Answer
A	A type of amplifier that uses switching technology to achieve high efficiency
B	A low power amplifier that uses a differential amplifier for improved linearity
C	An amplifier that uses drift-mode FETs for high efficiency
D	A frequency doubling amplifier

33. - E7C10

Which of the following filters would be the best choice for use in a 2 meter band repeater duplexer?

Select	Answer
A	A DSP filter
B	A crystal filter
C	A cavity filter
D	An L-C filter

34. - E7D10

What is the primary reason that a high-frequency switching type high-voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

Select	Answer
A	It uses a large power factor compensation capacitor to recover power from the unused portion of the AC cycle
B	The high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
C	It uses a diode bridge rectifier for increased output
D	The inverter design does not require any output filtering

35. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	A pre-emphasis network
B	A de-emphasis network
C	A heterodyne enhancer
D	A heterodyne suppressor

36. - E7F07

What function is performed by a Fast Fourier Transform?

Select	Answer
A	Converting digital signals from the time domain to the frequency domain
B	Converting analog signals to digital form
C	Converting 8-bit data to 16-bit data
D	Converting digital signals to analog form

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 maximum frequency for a filter circuit using that type of amplifier
D	The frequency at which the open-loop gain of the amplifier equals one

38. - E7H14

What is a phase-locked loop circuit?

Select	Answer
A	An electronic circuit also known as a monostable multivibrator
B	An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
C	An electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
D	An electronic circuit consisting of a precision push-pull amplifier with a differential input

39. - E8A10

What is the purpose of a low-pass filter used in conjunction with a digital-to-analog converter?

Select	Answer
A	Remove harmonics from the output caused by the discrete analog levels generated
B	Lower the input bandwidth to increase the effective resolution
C	All these choices are correct
D	Improve accuracy by removing out-of-sequence codes from the input

40. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

Select	Answer
A	0.167
B	60
C	1.67
D	0.6

41. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By transmitting extra data that may be used to detect and correct transmission errors
B	By the receiving station repeating each block of three data characters
C	By varying the frequency shift of the transmitted signal according to a predefined algorithm
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	Low-pass filters at the transmitter output
B	Increase keying waveform rise and fall times
C	High-pass filters at the transmitter output
D	Reduce keying waveform rise and fall times

43. - E9A06

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

Select	Answer
A	317 watts
B	126 watts
C	300 watts
D	2000 watts

44. - E9B04

What is the front-to-back ratio of the radiation pattern shown in Figure E92?

Select	Answer
A	38 dB
B	15 dB
C	28 dB
D	3 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	The low-angle radiation decreases
C	Additional higher vertical angle lobes will appear
D	Fewer vertical angle lobes will be present

46. - E9D12

Which of the following would provide the best RF ground for your station?

Select	Answer
A	An electrically short connection to a metal water pipe
B	A 50-ohm resistor connected to ground
C	An electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
D	An electrically short connection to 3 or 4 interconnected ground rods via a series RF choke

47. - E9E06

Which of these feed line impedances would be suitable for constructing a quarter-wave Q-section for matching a 100-ohm loop to 50-ohm feed line?

Select	Answer
A	50 ohms
B	62 ohms
C	75 ohms
D	450 ohms

48. - E9F01

What is the velocity factor of a transmission line?

Select	Answer
A	The velocity of the wave in the transmission line multiplied by the velocity of light in a vacuum
B	The ratio of the characteristic impedance of the line to the terminating impedance
C	The velocity of the wave in the transmission line divided by the velocity of light in a vacuum
D	The index of shielding for coaxial cable

49. - E9G02

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

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

50. - E9H11

What feature of a cardioid pattern antenna makes it useful for direction finding?

Select	Answer
A	A very sharp peak
B	Broadband response
C	High radiation angle
D	A very sharp single null