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

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1. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Mica
B	Uranium Hexafluoride
C	Zinc oxide
D	Beryllium Oxide

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 an isotropic radiator
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 a dipole

3. - E1B03

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

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

4. - E1C04

What is meant by IARP?

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

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

Select	Answer
A	Only those of Amateur Extra Class operators
B	Any amateur station, subject to the privileges of the class of operator license held by the control operator
C	Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
D	Only those of General, Advanced or Amateur Extra Class operators

6. - E1E07

What should a VE do if a candidate fails to comply with the examiner's instructions during an amateur operator license examination?

Select	Answer
A	Warn the candidate that continued failure to comply will result in termination of the examination
B	Immediately terminate the candidate's examination
C	Allow the candidate to complete the examination, but invalidate the results
D	Immediately terminate everyone's examination and close the session

7. - E1F06

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

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

8. - E2A09

What do the terms L band and S band specify regarding satellite communications?

Select	Answer
A	The 23 centimeter and 13 centimeter bands
B	The 2 meter and 70 centimeter bands
C	FM and Digital Store-and-Forward systems
D	Which sideband to use

9. - E2B07

What is the name of the signal component that carries color information in NTSC video?

Select	Answer
A	Chroma
B	Luminance
C	Spectral intensity
D	Hue

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	Frequencies shared with various unlicensed wireless data services
C	HF frequencies where digital communications are permitted
D	The 60 meter band channel centered on 5373 kHz

11. - E2D09

What type of modulation is used for JT65 contacts?

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

12. - E2E07

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

Select	Answer
A	Your transmit frequency is incorrect
B	Another station you are unable to hear is using the frequency
C	The protocol version you are using is not supported by the digital station
D	All these choices are correct

13. - E3A12

What is the cause of auroral activity?

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

14. - E3B03

What is the best time of day for transequatorial propagation?

Select	Answer
A	Morning
B	Afternoon or early evening
C	Late at night
D	Noon

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. - E4A02

Which of the following parameters does a spectrum analyzer display on the vertical and horizontal axes?

Select	Answer
A	SWR and frequency
B	RF amplitude and time
C	RF amplitude and frequency
D	SWR and time

17. - E4B11

Which of the following can be measured with a vector network analyzer?

Select	Answer
A	Input impedance
B	Reflection coefficient
C	Output impedance
D	All these choices are correct

18. - E4C02

Which of the following receiver circuits can be effective in eliminating interference from strong out-of-band signals?

Select	Answer
A	A notch filter
B	A properly adjusted product detector
C	A front-end filter or pre-selector
D	A narrow IF filter

19. - E4D05

What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

Select	Answer
A	146.10 MHz and 147.30 MHz
B	146.88 MHz and 146.34 MHz
C	146.34 MHz and 146.61 MHz
D	173.35 MHz and 139.40 MHz

20. - E4E01

What problem can occur when using an automatic notch filter (ANF) to remove interfering carriers while receiving CW signals?

Select	Answer
A	Received CW signals will appear to be modulated at the DSP clock frequency
B	Any nearby signal passing through the DSP system will overwhelm the desired signal
C	Ringing in the DSP filter will completely remove the spaces between the CW characters
D	Removal of the CW signal as well as the interfering carrier

21. - E5A14

What is the resonant frequency of an RLC circuit if R is 22 ohms, L is 50 microhenries and C is 40 picofarads?

Select	Answer
A	44.72 MHz
B	3.56 MHz
C	22.36 MHz
D	1.78 MHz

22. - E5B12

What is admittance?

Select	Answer
A	The turns ratio of a transformer
B	The inverse of impedance
C	The term for the gain of a field effect transistor
D	The inverse of Q factor

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 6
D	Point 5

24. - E5D02

Why is it important to keep lead lengths short for components used in circuits for VHF and above?

Select	Answer
A	To avoid unwanted inductive reactance
B	All these choices are correct
C	To increase the thermal time constant
D	To maintain component lifetime

25. - E6A07

Which of the following indicates that a silicon NPN junction transistor is biased on?

Select	Answer
A	Base-to-emitter resistance of approximately 0.6 to 0.7 ohms
B	Base-to-emitter voltage of approximately 6 to 7 volts
C	Base-to-emitter voltage of approximately 0.6 to 0.7 volts
D	Base-to-emitter resistance of approximately 6 to 7 ohms

26. - E6B09

What is a common use for point-contact diodes?

Select	Answer
A	As a high-voltage rectifier
B	As a constant voltage source
C	As an RF detector
D	As a constant current source

27. - E6C08

In Figure E6-3, what is the schematic symbol for a NAND gate?

Select	Answer
A	4
B	2
C	3
D	1

28. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

Select	Answer
A	Electrolytic capacitors
B	Steel-core toroids
C	Butterworth filters
D	Ferrite beads

29. - E6E07

What type of transmission line is used for connections to MMICs?

Select	Answer
A	Circular waveguide
B	Miniature coax
C	Parallel wire
D	Microstrip

30. - E6F11

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

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

31. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It maintains a constant output voltage, regardless of variations in the input voltage
B	It stores one bit of data in either a 0 or 1 state
C	It produces a continuous square wave oscillating between 1 and 0
D	It switches momentarily to the opposite binary state and then returns to its original state after a set time

32. - E7B06

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

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

33. - E7C08

Which of the following factors has the greatest effect on the bandwidth and response shape of a crystal ladder filter?

Select	Answer
A	The amplitude of the signals passing through the filter
B	The relative frequencies of the individual crystals
C	The gain of the RF stage preceding the filter
D	The DC voltage applied to the quartz crystal

34. - E7D09

What is the main reason to use a charge controller with a solar power system?

Select	Answer
A	Prevention of battery damage due to overcharge
B	Prevention of battery undercharge
C	Control of electrolyte levels during battery discharge
D	Matching of day and night charge rates

35. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

Select	Answer
A	Two and four times the original frequency
B	The square root of the product of input frequencies
C	The two input frequencies along with their sum and difference frequencies
D	1.414 and 0.707 times the input frequency

36. - E7F12

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters can delay all frequency components of the signal by the same amount
B	FIR filters can respond faster to impulses
C	All these choices are correct
D	FIR filters are easier to implement for a given set of passband rolloff requirements

37. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E73 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	24
B	94
C	47
D	0.21

38. - E7H06

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

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

39. - E8A08

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

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

40. - E8B02

How does the modulation index of a phase-modulated emission vary with RF carrier frequency?

Select	Answer
A	It does not depend on the RF carrier frequency
B	It increases as the RF carrier frequency increases
C	It varies with the square root of the RF carrier frequency
D	It decreases as the RF carrier frequency increases

41. - E8C06

What is the bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

Select	Answer
A	1.0 kHz
B	0.3 kHz
C	0.5 kHz
D	0.1 Hz

42. - E8D07

What is a common cause of overmodulation of AFSK signals?

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

43. - E9A04

Which of the following factors affect the feed point impedance of an antenna?

Select	Answer
A	Transmission line length
B	The settings of an antenna tuner at the transmitter
C	Antenna height
D	The input power level

44. - E9B08

What is the far field of an antenna?

Select	Answer
A	The region where radiated power dissipates over a specified time period
B	The region where radiated field strengths are constant
C	The region where the shape of the antenna pattern is independent of distance
D	The region of the ionosphere where radiated power is not refracted

45. - E9C08

What is a folded dipole antenna?

Select	Answer
A	A dipole configured to provide forward gain
B	A type of ground-plane antenna
C	A dipole one-quarter wavelength long
D	A half-wave dipole with an additional parallel wire connecting its two ends

46. - E9D02

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

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

47. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

Select	Answer
A	To cancel the inductive reactance of the matching network
B	To transform the antenna impedance to a higher value
C	To provide a rejection notch that prevents the radiation of harmonics
D	To provide DC isolation between the feed line and the antenna

48. - E9F09

What is the approximate physical length of a foam polyethylene dielectric coaxial transmission line that is electrically 1/4 wavelength long at 7.2 MHz?

Select	Answer
A	5.2 meters
B	10.4 meters
C	6.9 meters
D	8.3 meters

49. - E9G10

What do the arcs on a Smith chart represent?

Select	Answer
A	Points with constant reactance
B	SWR
C	Points with constant resistance
D	Frequency

50. - E9H09

What is a Pennant antenna?

Select	Answer
A	A small, vertically oriented receiving antenna consisting of a triangular loop terminated in approximately 900 ohms
B	A four-element, high-gain vertical array invented by George Pennant
C	A stealth antenna built to look like a flagpole
D	A form of rhombic antenna terminated in a variable capacitor to provide frequency diversity

Figure E5-1

Figure E6-3