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

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

3. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historic Places?

Select	Answer
A	A letter of intent must be filed with the Environmental Protection Agency
B	An Environmental Assessment must be submitted to the FCC
C	A form FSD-15 must be submitted to the Department of the Interior
D	A proposal must be submitted to the National Park Service

4. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

Select	Answer
A	IARP agreement
B	CEPT agreement
C	ITU reciprocal license
D	All these choices are correct

5. - E1D03

What is a space telecommand station?

Select	Answer
A	An amateur station located in a satellite or a balloon more than 50 kilometers above the surface of the Earth
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 that transmits communications to initiate, modify or terminate functions of a space station
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	Destroy the application form
B	Return the application document to the examinee
C	Send the application form to the FCC and inform the FCC of the grade
D	Maintain the application form with the VEC's records

7. - E1F08

Which of the following types of amateur station communications are prohibited?

Select	Answer
A	Communications that have political content, except as allowed by the Fairness Doctrine
B	Communications in a language other than English
C	Communications transmitted for hire or material compensation, except as otherwise provided in the rules
D	Communications that have religious content

8. - E2A13

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

Select	Answer
A	Multi-satellite relaying
B	Store-and-forward
C	Digipeating
D	Node hopping

9. - E2B11

What is the function of the Vertical Interval Signaling (VIS) code sent as part of an SSTV transmission?

Select	Answer
A	To lock the color burst oscillator in color SSTV images
B	To identify the SSTV mode being used
C	To identify the call sign of the station transmitting
D	To provide vertical synchronization

10. - E2C02

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

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

11. - E2D01

Which of the following digital modes is designed for meteor scatter communications?

Select	Answer
A	WSPR
B	MSK144
C	Hellschreiber
D	APRS

12. - E2E03

How is the timing of FT4 contacts organized?

Select	Answer
A	Alternating transmissions at 7.5 second intervals
B	It depends on the lunar phase
C	By exchanging ACK/NAK packets
D	Stations take turns on alternate days

13. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

Select	Answer
A	When the MUF is above 30 MHz
B	When the moon is at perigee
C	When the moon is full
D	When the moon is at apogee

14. - E3B12

What is the primary characteristic of chordal hop propagation?

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

15. - E3C14

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

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

16. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Modulation monitor
B	Logic analyzer
C	Bit error rate tester
D	Network analyzer

17. - E4B05

What three test loads are used to calibrate an RF vector network analyzer?

Select	Answer
A	Short circuit, open circuit, and resonant circuit
B	50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable
C	50 ohms, 75 ohms, and 90 ohms
D	Short circuit, open circuit, and 50 ohms

18. - E4C03

What is the term for the suppression in an FM receiver of one signal by another stronger signal on the same frequency?

Select	Answer
A	Frequency discrimination
B	Desensitization
C	Capture effect
D	Cross-modulation interference

19. - E4D08

What causes intermodulation in an electronic circuit?

Select	Answer
A	Positive feedback
B	Nonlinear circuits or devices
C	Too little gain
D	Lack of neutralization

20. - E4E11

What could cause local AM broadcast band signals to combine to generate spurious signals in the MF or HF bands?

Select	Answer
A	One or more of the broadcast stations is transmitting an over-modulated signal
B	Your station receiver IF amplifier stage is defective
C	You are receiving skywave signals from a distant station
D	Nearby corroded metal joints are mixing and re-radiating the broadcast signals

21. - E5A08

What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?

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

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 and current are in phase
C	Voltage leads current by 90 degrees
D	Voltage and current are 180 degrees out of phase

23. - E5C09

When using rectangular coordinates to graph the impedance of a circuit, what do the axes represent?

Select	Answer
A	The X axis represents the resistive component and the Y axis represents the reactive component
B	The X axis represents the magnitude and the Y axis represents the phase angle
C	The X axis represents the reactive component and the Y axis represents the resistive component
D	The X axis represents the phase angle and the Y axis represents the magnitude

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	0.5
B	0.707
C	0.866
D	1.0

25. - E6A11

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

Select	Answer
A	2
B	3
C	6
D	1

26. - E6B03

What type of bias is required for an LED to emit light?

Select	Answer
A	Inductive bias
B	Reverse bias
C	Zero bias
D	Forward bias

27. - E6C10

In Figure E6-3, what is the schematic symbol for a NOR gate?

Select	Answer
A	3
B	2
C	1
D	4

28. - E6D06

What core material property determines the inductance of an inductor?

Select	Answer
A	Thermal impedance
B	Reactivity
C	Permeability
D	Resistance

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	Axial lead
C	Surface mount
D	TO-220

30. - E6F09

What is the efficiency of a photovoltaic cell?

Select	Answer
A	The output RF power divided by the input DC power
B	The relative fraction of light that is converted to current
C	The open-circuit voltage divided by the short-circuit current under full illumination
D	Cost per kilowatt-hour generated

31. - E7A01

Which circuit is bistable?

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

32. - E7B05

What can be done to prevent unwanted oscillations in an RF power amplifier?

Select	Answer
A	Tune both the input and output for maximum power
B	Tune the stage for maximum SWR
C	Install parasitic suppressors and/or neutralize the stage
D	Use a phase inverter in the output filter

33. - E7C04

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

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

34. - E7D03

What device is typically used as a stable voltage reference in a linear voltage regulator?

Select	Answer
A	A Zener diode
B	A varactor diode
C	A tunnel diode
D	An SCR

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 heterodyne enhancer
C	A heterodyne suppressor
D	A de-emphasis network

36. - E7F06

What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

Select	Answer
A	10 bits
B	8 bits
C	4 bits
D	6 bits

37. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

Select	Answer
A	It increases linearly with increasing frequency
B	It does not vary with frequency
C	It decreases logarithmically with increasing frequency
D	It decreases linearly with increasing frequency

38. - E7H07

How can an oscillator's microphonic responses be reduced?

Select	Answer
A	Mechanically isolate the oscillator circuitry from its enclosure
B	Increase the bias voltage
C	Use NP0 capacitors
D	Reduce noise on the oscillator's power supply

39. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

Select	Answer
A	Immunity to out-of-sequence coding reduces spurious responses
B	Very high speed allows digitizing high frequencies
C	Very low power consumption decreases frequency drift
D	All these choices are correct

40. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

Select	Answer
A	1/3
B	6000
C	2000
D	3

41. - E8C10

How may data rate be increased without increasing bandwidth?

Select	Answer
A	Using a more efficient digital code
B	It is impossible
C	Using forward error correction
D	Increasing analog-to-digital conversion resolution

42. - E8D05

What is the most common method of reducing key clicks?

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

43. - E9A05

What is included in the total resistance of an antenna system?

Select	Answer
A	Transmission-line resistance plus radiation resistance
B	Radiation resistance plus loss resistance
C	Radiation resistance plus space impedance
D	Radiation resistance plus transmission resistance

44. - E9B11

What is a disadvantage of decreasing the number of wire segments in an antenna model below 10 segments per half-wavelength?

Select	Answer
A	The antenna will become mechanically unstable
B	The computed feed point impedance may be incorrect
C	Ground conductivity will not be accurately modeled
D	The resulting design will favor radiation of harmonic energy

45. - E9C13

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with increasing height above ground?

Select	Answer
A	The horizontal beamwidth increases
B	The takeoff angle of the lowest elevation lobe increases
C	The horizontal beamwidth decreases
D	The takeoff angle of the lowest elevation lobe decreases

46. - E9D10

What happens to feed-point impedance at the base of a fixed length HF mobile antenna when operated below its resonant frequency?

Select	Answer
A	The radiation resistance increases and the capacitive reactance increases
B	The radiation resistance decreases and the capacitive reactance increases
C	The radiation resistance decreases and the capacitive reactance decreases
D	The radiation resistance increases and the capacitive reactance decreases

47. - E9E07

What parameter describes the interactions at the load end of a mismatched transmission line?

Select	Answer
A	Reflection coefficient
B	Dielectric constant
C	Velocity factor
D	Characteristic impedance

48. - E9F04

What impedance does a 1/2-wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	Very high impedance
B	Very low impedance
C	The same as the characteristic impedance of the line
D	The same as the output impedance of the generator

49. - E9G07

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

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

50. - E9H10

How can the output voltage of a multiple-turn receiving loop antenna be increased?

Select	Answer
A	By increasing the number of turns and/or the area
B	By reducing the permeability of the loop shield
C	By utilizing high impedance wire for the coupling loop
D	By winding adjacent turns in opposing directions

Figure E6-1

Figure E6-3

Figure E9-3