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

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1. - E0A10

What toxic material may be present in some electronic components such as high voltage capacitors and transformers?

Select	Answer
A	Polymorphic silicon
B	Polychlorinated biphenyls
C	Polyethylene
D	Polytetrafluoroethylene

2. - E1A11

Which of the following describes authorization or licensing required when operating an amateur station aboard a U.S.-registered vessel in international waters?

Select	Answer
A	Only General Class or higher amateur licenses
B	Any FCC-issued amateur license
C	An unrestricted Radiotelephone Operator Permit
D	Any amateur license with an FCC Marine or Aircraft endorsement

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

4. - E1C07

At what level below a signal's mean power level is its bandwidth determined according to FCC rules?

Select	Answer
A	26 dB
B	3 dB
C	23 dB
D	6 dB

5. - E1D07

Which HF amateur bands have frequencies authorized for space stations?

Select	Answer
A	Only the 40, 30, 20, 15, 12, and 10 meter bands
B	All HF bands
C	Only the 40, 20, 17, 15, and 10 meter bands
D	Only the 40, 20, 17, 15, 12, and 10 meter bands

6. - E1E05

What is the minimum passing score on all amateur operator license examinations?

Select	Answer
A	Minimum passing score of 80%
B	Minimum passing score of 70%
C	Minimum passing score of 77%
D	Minimum passing score of 74%

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

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 creating errors in the satellite telemetry
C	To avoid reducing the downlink power to all other users
D	To prevent the satellite from emitting out-of-band signals

9. - E2B10

What aspect of an analog slow-scan television signal encodes the brightness of the picture?

Select	Answer
A	Tone frequency
B	Sync amplitude
C	Tone amplitude
D	Sync frequency

10. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

Select	Answer
A	Contacts using tactical call signs
B	Contacts between a U.S. station and a non-U.S. station
C	Repeater contacts between U.S. club members
D	Special event contacts between stations in the U.S.

11. - E2D05

What is one advantage of the JT65 mode?

Select	Answer
A	Permits fast-scan TV transmissions over narrow bandwidth
B	The ability to decode signals which have a very low signal-to-noise ratio
C	Easily copied by ear if necessary
D	Uses only a 65 Hz bandwidth

12. - E2E10

Which of these digital modes has the narrowest bandwidth?

Select	Answer
A	PSK31
B	170 Hz shift, 45-baud RTTY
C	300-baud packet
D	MFSK16

13. - E3A09

Which of the following frequency ranges is most suited for meteor scatter communications?

Select	Answer
A	1.8 MHz - 1.9 MHz
B	10 MHz - 14 MHz
C	220 MHz - 450 MHz
D	28 MHz - 148 MHz

14. - E3B09

At what time of year is sporadic E propagation most likely to occur?

Select	Answer
A	Around the solstices, especially the summer solstice
B	Around the equinoxes, especially the fall equinox
C	Around the equinoxes, especially the spring equinox
D	Around the solstices, especially the winter solstice

15. - E3C15

What might be indicated by a sudden rise in radio background noise across a large portion of the HF spectrum?

Select	Answer
A	A solar flare has occurred
B	Increased transequatorial propagation is likely
C	Long-path propagation is likely
D	A temperature inversion has occurred

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	SWR and time
C	RF amplitude and frequency
D	RF amplitude and time

17. - E4B11

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

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

18. - E4C01

What is an effect of excessive phase noise in a receiver's local oscillator?

Select	Answer
A	It can combine with strong signals on nearby frequencies to generate interference
B	It decreases receiver third-order intercept point
C	It can affect the receiver's frequency calibration
D	It limits the receiver's ability to receive strong signals

19. - E4D12

What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?

Select	Answer
A	Cross-modulation interference
B	Quieting
C	Squelch gain rollback
D	Desensitization

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

21. - E5A02

What is resonance in an LC or RLC circuit?

Select	Answer
A	The lowest frequency that will pass current
B	The frequency at which the capacitive reactance equals the inductive reactance
C	The highest frequency that will pass current
D	The frequency at which the reactive impedance equals the resistive impedance

22. - E5B08

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?

Select	Answer
A	76 degrees with the voltage leading the current
B	14 degrees with the voltage lagging the current
C	76 degrees with the voltage lagging the current
D	14 degrees with the voltage leading the current

23. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

Select	Answer
A	Near field diagram
B	Far field diagram
C	Phasor diagram
D	Venn diagram

24. - E5D03

What is microstrip?

Select	Answer
A	Precision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies
B	Short lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
C	Miniature coax used for low power applications
D	Lightweight transmission line made of common zip cord

25. - E6A06

What is the beta of a bipolar junction transistor?

Select	Answer
A	The breakdown voltage of the base to collector junction
B	The change in collector current with respect to base current
C	The switching speed
D	The frequency at which the current gain is reduced to 0.707

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	Low junction capacitance
C	Extremely high reverse breakdown voltage
D	Ability to dissipate large amounts of power

27. - E6C10

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

Select	Answer
A	2
B	4
C	3
D	1

28. - E6D06

What core material property determines the inductance of an inductor?

Select	Answer
A	Thermal impedance
B	Resistance
C	Reactivity
D	Permeability

29. - E6E09

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

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

30. - E6F04

What is the photovoltaic effect?

Select	Answer
A	The conversion of light to electrical energy
B	The conversion of electrical energy to mechanical energy
C	The conversion of voltage to current when exposed to light
D	The tendency of a battery to discharge when exposed to light

31. - E7A10

What is a truth table?

Select	Answer
A	A diagram showing logic states when the digital device output is true
B	A list of inputs and corresponding outputs for a digital device
C	A table of logic symbols that indicate the logic states of an op-amp
D	A table of logic symbols that indicate the high logic states of an op-amp

32. - E7B04

Where on the load line of a Class A common emitter amplifier would bias normally be set?

Select	Answer
A	At a point where the bias resistor equals the load resistor
B	Approximately halfway between saturation and cutoff
C	At a point where the load line intersects the zero bias current curve
D	Where the load line intersects the voltage axis

33. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

Select	Answer
A	It is a low-pass filter
B	It is a band-pass filter
C	It is a notch filter
D	It is a high-pass filter

34. - E7D02

What is a characteristic of a switching electronic voltage regulator?

Select	Answer
A	The resistance of a control element is varied in direct proportion to the line voltage or load current
B	It is generally less efficient than a linear regulator
C	The controlled device's duty cycle is changed to produce a constant average output voltage
D	It gives a ramp voltage at its output

35. - E7E04

What is one way a single-sideband phone signal can be generated?

Select	Answer
A	By using a balanced modulator followed by a filter
B	By using a reactance modulator followed by a mixer
C	By using a loop modulator followed by a mixer
D	By driving a product detector with a DSB signal

36. - E7F07

What function is performed by a Fast Fourier Transform?

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

37. - E7G05

How can unwanted ringing and audio instability be prevented in an op-amp RC audio filter circuit?

Select	Answer
A	Restrict Q but increase gain
B	Increase both gain and Q
C	Restrict both gain and Q
D	Restrict gain but increase Q

38. - E7H02

What is a microphonic?

Select	Answer
A	Distortion caused by RF pickup on the microphone cable
B	An IC used for amplifying microphone signals
C	Excess loading of the microphone by an oscillator
D	Changes in oscillator frequency due to mechanical vibration

39. - E8A10

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

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

40. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

Select	Answer
A	OFDM signals are not allowed on amateur bands
B	Extremely low-power contacts
C	EME
D	High-speed digital modes

41. - E8C05

What is the approximate bandwidth of a 13-WPM International Morse Code transmission?

Select	Answer
A	52 Hz
B	13 Hz
C	26 Hz
D	104 Hz

42. - E8D09

What is considered an acceptable maximum IMD level for an idling PSK signal?

Select	Answer
A	+10 dB
B	-30 dB
C	-20 dB
D	+15 dB

43. - E9A03

What is the radiation resistance of an antenna?

Select	Answer
A	The combined losses of the antenna elements and feed line
B	The resistance in the atmosphere that an antenna must overcome to be able to radiate a signal
C	The specific impedance of the antenna
D	The value of a resistance that would dissipate the same amount of power as that radiated from an antenna

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

45. - E9C04

What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

Select	Answer
A	The lobes become more perpendicular to the wire
B	The front-to-back ratio decreases
C	The lobes align more in the direction of the wire
D	The vertical angle increases

46. - E9D02

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

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

47. - E9E07

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

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

48. - E9F13

What impedance does a 1/4-wavelength transmission line present to a generator when the line is shorted at the far end?

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

49. - E9G08

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

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

50. - E9H05

What is the main drawback of a small wire-loop antenna for direction finding?

Select	Answer
A	It is practical for use only on VHF and higher bands
B	It has a bidirectional pattern
C	All these choices are correct
D	It has no clearly defined null

Figure E6-3