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

2. - E1A05

What is the maximum power output permitted on the 60 meter band?

Select	Answer
A	100 watts PEP effective radiated power relative to an isotropic radiator
B	50 watts PEP effective radiated power relative to a dipole
C	100 watts PEP effective radiated power relative to the gain of a half-wave dipole
D	50 watts PEP effective radiated power relative to an isotropic radiator

3. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	10 miles
B	1 mile
C	3 miles
D	30 miles

4. - E1C04

What is meant by IARP?

Select	Answer
A	An indication of increased antenna reflected power
B	An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
C	The internal amateur radio practices policy of the FCC
D	A forecast of intermittent aurora radio propagation

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 that receives telemetry from a satellite or balloon more than 50 kilometers above the surface of the Earth
C	An amateur station located in a satellite or a balloon more than 50 kilometers above the surface of the Earth
D	An amateur station located on the surface of the Earth for communication with other Earth stations by means of Earth satellites

6. - E1E12

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

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

7. - E1F07

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

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

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. - E2B06

What is vestigial sideband modulation?

Select	Answer
A	Spread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation
B	A type of modulation in which one sideband is inverted
C	Amplitude modulation in which one complete sideband and a portion of the other are transmitted
D	Narrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier

10. - E2C04

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

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

11. - E2D03

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

Select	Answer
A	JT65
B	PACTOR III
C	MSK144
D	Olivia

12. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Direct FSK applies the data signal to the transmitter VFO, while AFSK transmits tones via phone
B	Only direct FSK can be decoded by computer
C	Direct FSK can transmit faster baud rates
D	Direct FSK occupies less bandwidth

13. - E3A02

What characterizes libration fading of an EME signal?

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

14. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

Select	Answer
A	1000 miles
B	2500 miles
C	7500 miles
D	5000 miles

15. - E3C07

Which of the following descriptors indicates the greatest solar flare intensity?

Select	Answer
A	Class B
B	Class M
C	Class A
D	Class X

16. - E4A04

How is the compensation of an oscilloscope probe typically adjusted?

Select	Answer
A	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
B	A frequency standard is displayed and the probe is adjusted until the deflection time is accurate
C	A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
D	A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude

17. - E4B03

Which S parameter is equivalent to forward gain?

Select	Answer
A	S12
B	S21
C	S22
D	S11

18. - E4C13

How does a narrow-band roofing filter affect receiver performance?

Select	Answer
A	It improves intelligibility by using low Q circuitry to reduce ringing
B	It improves sensitivity by reducing front end noise
C	It improves dynamic range by attenuating strong signals near the receive frequency
D	All these choices are correct

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

20. - E4E06

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

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

21. - E5A15

Which of the following increases Q for inductors and capacitors?

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

22. - E5B09

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

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

23. - E5C04

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

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

24. - E5D10

How can the true power be determined in an AC circuit where the voltage and current are out of phase?

Select	Answer
A	By multiplying the apparent power by the power factor
B	By dividing the apparent power by the power factor
C	By dividing the reactive power by the power factor
D	By multiplying the reactive power by the power factor

25. - E6A04

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

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

26. - E6B07

What is the failure mechanism when a junction diode fails due to excessive current?

Select	Answer
A	Excessive junction temperature
B	Excessive inverse voltage
C	Charge carrier depletion
D	Insufficient forward voltage

27. - E6C11

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

Select	Answer
A	2
B	6
C	4
D	5

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

29. - E6E09

Which of the following component package types would be most suitable for use at frequencies above the HF range?

Select	Answer
A	Radial lead
B	TO-220
C	Axial lead
D	Surface mount

30. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

Select	Answer
A	It decreases
B	It increases
C	It stays the same
D	It becomes unstable

31. - E7A04

How many flip-flops are required to divide a signal frequency by 4?

Select	Answer
A	8
B	4
C	2
D	1

32. - E7B07

Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?

Select	Answer
A	Reduced intermodulation products
B	Signal inversion
C	Increased overall intelligibility
D	Signal distortion and excessive bandwidth

33. - E7C05

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

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

34. - E7D13

What is the equation for calculating power dissipated by a series linear voltage regulator?

Select	Answer
A	Output voltage multiplied by output current
B	Input voltage multiplied by input current
C	Voltage difference from input to output multiplied by output current
D	Input voltage divided by output current

35. - E7E02

What is the function of a reactance modulator?

Select	Answer
A	To produce AM signals by using an electrically variable inductance or capacitance
B	To produce AM signals by using an electrically variable resistance
C	To produce PM or FM signals by using an electrically variable inductance or capacitance
D	To produce PM signals by using an electrically variable resistance

36. - E7F02

What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

Select	Answer
A	A phase-inverting filter
B	A crystal-lattice filter
C	An adaptive filter
D	A Hilbert-transform filter

37. - E7G10

What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 1800 ohms and RF is 68 kilohms?

Select	Answer
A	76
B	0.03
C	1
D	38

38. - E7H01

What are three oscillator circuits used in amateur radio equipment?

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

39. - E8A09

How many different input levels can be encoded by an analog-to-digital converter with 8-bit resolution?

Select	Answer
A	256
B	8
C	8 multiplied by the gain of the input amplifier
D	256 divided by the gain of the input amplifier

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 decreases as the RF carrier frequency increases
C	It increases as the RF carrier frequency increases
D	It does not depend on the RF carrier frequency

41. - E8C07

What is the bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

Select	Answer
A	9.6 kHz
B	4.8 kHz
C	5.76 kHz
D	15.36 kHz

42. - E8D07

What is a common cause of overmodulation of AFSK signals?

Select	Answer
A	Excessive transmit audio levels
B	Ground loops
C	Excessive numbers of retries
D	Bit errors in the modem

43. - E9A09

What is antenna efficiency?

Select	Answer
A	Radiation resistance divided by transmission resistance
B	Total resistance divided by radiation resistance
C	Effective radiated power divided by transmitter output
D	Radiation resistance divided by total resistance

44. - E9B09

What type of computer program technique is commonly used for modeling antennas?

Select	Answer
A	Method of Moments
B	Calculus differentiation with respect to physical properties
C	Graphical analysis
D	Mutual impedance analysis

45. - E9C03

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed in phase?

Select	Answer
A	Cardioid
B	Omni-directional
C	A Figure-8 end-fire along the axis of the array
D	A Figure-8 broadside to the axis of the array

46. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
B	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes
C	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
D	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase

47. - E9E09

Which of the following is used to shunt-feed a grounded tower at its base?

Select	Answer
A	All these choices are correct
B	Hairpin match
C	Double-bazooka match
D	Gamma match

48. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically 1/4 wavelength long at 14.1 MHz?

Select	Answer
A	4.3 meters
B	5.3 meters
C	10.6 meters
D	3.5 meters

49. - E9G08

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

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

50. - E9H08

What is the function of a sense antenna?

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

Figure E6-3

Figure E7-3