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

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1. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Ensure signals from your station are less than the uncontrolled Maximum Permitted Emission (MPE) limits
B	Ensure signals from your station are less than the uncontrolled Maximum Permitted Exposure (MPE) limits
C	Ensure signals from your station are less than the controlled Maximum Permitted Emission (MPE) limits
D	Ensure signals from your station are less than the controlled Maximum Permitted Exposure (MPE) limits

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

3. - E1B12

What must the control operator of a repeater operating in the 70 cm band do if a radiolocation system experiences interference from that repeater?

Select	Answer
A	Cease operation or make changes to the repeater to mitigate the interference
B	File an FAA NOTAM (Notice to Airmen) with the repeater system's ERP, call sign, and six-character grid locator
C	Reduce the repeater antenna HAAT (Height Above Average Terrain)
D	All these choices are correct

4. - E1C10

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHz?

Select	Answer
A	At least 73 dB below
B	At least 53 dB below
C	At least 43 dB below
D	At least 63 dB below

5. - E1D10

Which amateur stations are eligible to be telecommand stations of space stations (subject to the privileges of the class of operator license held by the control operator of the station)?

Select	Answer
A	All these choices are correct
B	Any amateur station so designated by the ITU
C	Any amateur station designated by NASA
D	Any amateur station so designated by the space station licensee

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

7. - E1F02

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

Select	Answer
A	Full privileges, up to and including those of the Amateur Extra Class license, on the 80, 40, 20, 15, and 10 meter bands
B	None, they must obtain a U.S. license
C	The operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Amateur Extra Class license privileges
D	All privileges of the Amateur Extra Class license

8. - E2A04

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

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

9. - E2B02

How many horizontal lines make up a fast-scan (NTSC) television frame?

Select	Answer
A	30
B	60
C	1080
D	525

10. - E2C01

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control and the remote transmitter is located in the U.S.?

Select	Answer
A	/ followed by the ARRL Section of the remote station
B	/ followed by the USPS two-letter abbreviation for the state in which the remote station is located
C	/R# where # is the district of the remote station
D	No additional indicator is required

11. - E2D07

What digital protocol is used by APRS?

Select	Answer
A	AMTOR
B	PACTOR
C	802.11
D	AX.25

12. - E2E12

How do ALE stations establish contact?

Select	Answer
A	ALE radios monitor an internet site for the frequency they are being paged on
B	ALE radios send a constant tone code to establish a frequency for future use
C	ALE constantly scans a list of frequencies, activating the radio when the designated call sign is received
D	ALE radios activate when they hear their signal echoed by back scatter

13. - E3A11

What is a typical range for tropospheric propagation of microwave signals?

Select	Answer
A	2500 miles
B	10 miles to 50 miles
C	100 miles to 300 miles
D	1200 miles

14. - E3B11

At what time of day can sporadic E propagation occur?

Select	Answer
A	Only around sunset and sunrise
B	Only in hours of darkness
C	Any time
D	Only around sunset

15. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

Select	Answer
A	Downward bending due to density variations in the atmosphere
B	Due to the Doppler effect
C	E-region skip
D	D-region skip

16. - E4A07

Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge to measure antenna SWR?

Select	Answer
A	Antenna analyzers automatically tune your antenna for resonance
B	Antenna analyzers display a time-varying representation of the modulation envelope
C	Antenna analyzers do not need an external RF source
D	All these choices are correct

17. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

Select	Answer
A	75 watts
B	100 watts
C	25 watts
D	125 watts

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

19. - E4D02

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

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

20. - E4E06

What is one type of electrical interference that might be caused by a nearby personal computer?

Select	Answer
A	A loud AC hum in the audio output of your station receiver
B	A whining type noise that continually pulses off and on
C	The appearance of unstable modulated or unmodulated signals at specific frequencies
D	A clicking noise at intervals of a few seconds

21. - E5A15

Which of the following increases Q for inductors and capacitors?

Select	Answer
A	Lower reactance
B	Lower losses
C	Higher self-resonant frequency
D	Lower self-resonant frequency

22. - E5B02

What letter is commonly used to represent susceptance?

Select	Answer
A	G
B	X
C	Y
D	B

23. - E5C04

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

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

24. - E5D01

What is the result of skin effect?

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

25. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

Select	Answer
A	N-type impurity
B	Insulator impurity
C	Acceptor impurity
D	Donor impurity

26. - E6B10

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

Select	Answer
A	6
B	7
C	5
D	1

27. - E6C01

What is the function of hysteresis in a comparator?

Select	Answer
A	To cause the output to change states continually
B	To increase the sensitivity
C	To allow the comparator to be used with AC input signals
D	To prevent input noise from causing unstable output signals

28. - E6D03

Which of the following is an aspect of the piezoelectric effect?

Select	Answer
A	Mechanical deformation of material by the application of a magnetic field
B	Generation of electrical energy in the presence of light
C	Mechanical deformation of material by the application of a voltage
D	Increased conductivity in the presence of light

29. - E6E12

Why are DIP through-hole package ICs not typically used at UHF and higher frequencies?

Select	Answer
A	Epoxy coating is conductive above 300 MHz
B	Unsuitable for combining analog and digital signals
C	Too many pins
D	Excessive lead length

30. - E6F11

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

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

31. - E7A07

What logical operation does a NAND gate perform?

Select	Answer
A	It produces logic 0 at its output only when all inputs are logic 1
B	It produces logic 0 at its output if some but not all inputs are logic 1
C	It produces logic 1 at its output only when all inputs are logic 1
D	It produces logic 0 at its output only when all inputs are logic 0

32. - E7B06

Which of the following amplifier types reduces even-order harmonics?

Select	Answer
A	Push-push
B	Class C
C	Push-pull
D	Class AB

33. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

Select	Answer
A	A passive op-amp filter
B	A Butterworth filter
C	An active LC filter
D	A Chebyshev filter

34. - E7D11

What is the function of the pass transistor in a linear voltage regulator circuit?

Select	Answer
A	Maintains nearly constant output impedance over a wide range of load current
B	Maintains nearly constant output voltage over a wide range of load current
C	Provides a stable input impedance over a wide range of source voltage
D	Permits a wide range of output voltage settings

35. - E7E10

How does a diode envelope detector function?

Select	Answer
A	By rectification and filtering of RF signals
B	By sensing the change of reactance in the diode with respect to frequency
C	By mixing signals with noise in the transition region of the diode
D	By breakdown of the Zener voltage

36. - E7F07

What function is performed by a Fast Fourier Transform?

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

37. - E7G12

What is an operational amplifier?

Select	Answer
A	An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit
B	A RF amplifier used in the UHF and microwave regions
C	A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance
D	A digital audio amplifier whose characteristics are determined by components external to the amplifier

38. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

Select	Answer
A	A direct digital synthesizer
B	A hybrid synthesizer
C	A diode-switching matrix synthesizer
D	A phase-locked loop synthesizer

39. - E8A11

Which of the following is a measure of the quality of an analog-to-digital converter?

Select	Answer
A	Total harmonic distortion
B	Peak envelope power
C	Power factor
D	Reciprocal mixing

40. - E8B09

What is deviation ratio?

Select	Answer
A	The ratio of the highest audio modulating frequency to the average audio modulating frequency
B	The ratio of the audio modulating frequency to the center carrier frequency
C	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
D	The ratio of the carrier center frequency to the audio modulating frequency

41. - E8C09

Which digital code allows only one bit to change between sequential code values?

Select	Answer
A	Gray code
B	Extended Binary Coded Decimal Interchange Code
C	Binary Coded Decimal Code
D	Excess 3 code

42. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

Select	Answer
A	More difficult to copy
B	The generation of RF harmonics
C	Limits data speed
D	The generation of key clicks

43. - E9A07

What is the effective isotropic radiated power of a repeater station with 200 watts transmitter power output, 2 dB feed line loss, 2.8 dB duplexer loss, 1.2 dB circulator loss, and 7 dBi antenna gain?

Select	Answer
A	252 watts
B	63.2 watts
C	632 watts
D	159 watts

44. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the beamwidth?

Select	Answer
A	30 degrees
B	50 degrees
C	75 degrees
D	25 degrees

45. - E9C14

How does the performance of a horizontally polarized antenna mounted on the side of a hill compare with the same antenna mounted on flat ground?

Select	Answer
A	The main lobe takeoff angle increases in the downhill direction
B	The horizontal beamwidth increases in the uphill direction
C	The main lobe takeoff angle decreases in the downhill direction
D	The horizontal beamwidth decreases in the downhill direction

46. - E9D03

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

Select	Answer
A	As low as possible on the vertical radiator
B	As close to the transmitter as possible
C	At a voltage node
D	Near the center of the vertical radiator

47. - E9E05

How must an antenna's driven element be tuned to use a hairpin matching system?

Select	Answer
A	The driven element reactance must be inductive
B	The driven element radiation resistance must be higher than the characteristic impedance of the transmission line
C	The driven element resonance must be lower than the operating frequency
D	The driven element reactance must be capacitive

48. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically 1/2 wavelength long at 14.10 MHz?

Select	Answer
A	7.0 meters
B	13.3 meters
C	8.5 meters
D	10.6 meters

49. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning prime center with regard to the reactance axis
B	Reassigning reactance values with regard to the resistance axis
C	Reassigning impedance values with regard to the prime center
D	Reassigning resistance values with regard to the reactance axis

50. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	All these choices are correct
B	Atmospheric noise is so high that gain over a dipole is not important
C	They must be erected at least 1/2 wavelength above the ground to attain good directivity
D	Low loss coax transmission line is essential for good performance

Figure E6-2

Figure E9-1