US Amateur Radio - Amateur Extra (Element 4, 2016-2020) Practice Test

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1. - E1A04

With your transceiver displaying the carrier frequency of phone signals, you hear a DX station calling CQ on 3.601 MHz LSB. Is it legal to return the call using lower sideband on the same frequency?

Select	Answer
A	Yes, because the displayed frequency is within the 75 meter phone band segment
B	No, U.S. stations are not permitted to use phone emissions below 3.610 MHz
C	No, the sideband will extend beyond the edge of the phone band segment
D	Yes, because the DX station initiated the contact

2. - E1B09

Which amateur stations may be operated under RACES rules?

Select	Answer
A	Any FCC-licensed amateur station except a Technician class
B	Any FCC-licensed amateur station certified by the responsible civil defense organization for the area served
C	Any FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)
D	Only those club stations licensed to Amateur Extra class operators

3. - E1C08

What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?

Select	Answer
A	30 seconds
B	10 minutes
C	3 minutes
D	5 minutes

4. - 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	Only those of General, Advanced or Amateur Extra Class operators
D	Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau

5. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

Select	Answer
A	Revocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
B	All of these choices are correct
C	A sentence of up to one year in prison
D	A fine of up to $1000 per occurrence

6. - E1F12

Who may be the control operator of an auxiliary station?

Select	Answer
A	Only Amateur Extra Class operators
B	Only Technician, General, Advanced or Amateur Extra Class operators
C	Any licensed amateur operator
D	Only General, Advanced or Amateur Extra Class operators

7. - E2A05

What do the letters in a satellite's mode designator specify?

Select	Answer
A	Power limits for uplink and downlink transmissions
B	The location of the ground control station
C	The polarization of uplink and downlink signals
D	The uplink and downlink frequency ranges

8. - E2B07

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

Select	Answer
A	Spectral Intensity
B	Hue
C	Luminance
D	Chroma

9. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of activity?

Select	Answer
A	In the middle of each band, usually on the national calling frequency
B	In the weak signal segment of the band, with most of the activity near the calling frequency
C	In the middle of the band, usually 25 kHz above the national calling frequency
D	At the top of each band, usually in a segment reserved for contests

10. - E2D12

How does JT65 improve EME communications?

Select	Answer
A	All of these choices are correct
B	It can decode signals many dB below the noise floor using FEC
C	It supplies signals to guide the antenna to track the Moon
D	It controls the receiver to track Doppler shift

11. - E2E05

Which type of digital mode does not support keyboard-to-keyboard operation?

Select	Answer
A	Winlink
B	RTTY
C	MFSK
D	PSK31

12. - E3A16

Which of the following best describes electromagnetic waves traveling in free space?

Select	Answer
A	The energy propagates through a medium with a high refractive index
B	Changing electric and magnetic fields propagate the energy
C	Electric and magnetic fields become aligned as they travel
D	The waves are reflected by the ionosphere and return to their source

13. - E3B14

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

Select	Answer
A	They become elliptically polarized
B	They are bent toward the magnetic poles
C	They become phase-locked
D	Their polarization is randomly modified

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

Select	Answer
A	It increases
B	It peaks at roughly 14 MHz
C	It stays the same
D	It decreases

15. - E4A15

What is an advantage of a period-measuring frequency counter over a direct-count type?

Select	Answer
A	It can run on battery power for remote measurements
B	It provides improved resolution of low-frequency signals within a comparable time period
C	It can directly measure the modulation index of an FM transmitter
D	It does not require an expensive high-precision time base

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S21
B	S12
C	S22
D	S11

17. - E4C16

Which of the following is caused by missing codes in an SDR receiver's analog-to-digital converter?

Select	Answer
A	Loss of sensitivity
B	Overload
C	Excess output level
D	Distortion

18. - E4D02

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

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

19. - E4E04

How can conducted and radiated noise caused by an automobile alternator be suppressed?

Select	Answer
A	By installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead
B	By connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads
C	By installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead
D	By installing a noise suppression resistor and a blocking capacitor in both leads

20. - E5A07

What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

Select	Answer
A	L/R
B	Maximum
C	R/L
D	Minimum

21. - E5B09

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

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

22. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

Select	Answer
A	A positive phase angle
B	A negative real part
C	A positive real part
D	A negative phase angle

23. - E5D07

What determines the strength of the magnetic field around a conductor?

Select	Answer
A	The diameter of the conductor
B	The amount of current flowing through the conductor
C	The resistance divided by the current
D	The ratio of the current to the resistance

24. - E6A10

In Figure E6-2, what is the schematic symbol for an N-channel dual-gate MOSFET?

Select	Answer
A	6
B	4
C	5
D	2

25. - E6B10

In Figure E6-3, what is the schematic symbol for a light-emitting diode?

Select	Answer
A	1
B	7
C	5
D	6

26. - E6C03

What is tri-state logic?

Select	Answer
A	Logic devices that utilize ternary math
B	Low power logic devices designed to operate at 3 volts
C	Proprietary logic devices manufactured by Tri-State Devices
D	Logic devices with 0, 1, and high impedance output states

27. - E6D03

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

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

28. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

Select	Answer
A	A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
B	Two chips in each package (Dual In Package)
C	Low leakage doubly insulated package
D	Package mounts in a direct inverted position

29. - E6F09

What is the efficiency of a photovoltaic cell?

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

30. - E7A09

What logical operation is performed by an exclusive NOR gate?

Select	Answer
A	It produces logic "0" at its output only if all inputs are logic "0"
B	It produces logic "0" at its output if any single input is logic "1"
C	It produces logic "1" at its output if any single input is logic "1"
D	It produces logic "1" at its output only if all inputs are logic "1"

31. - E7B06

Which of the following amplifier types reduces or eliminates even order harmonics?

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

32. - E7C06

What are the distinguishing features of an elliptical filter?

Select	Answer
A	Gradual passband rolloff with extreme stop band ripple
B	Extremely flat response over its pass band with gradually rounded stop band corners
C	Extremely sharp cutoff with one or more notches in the stop band
D	Gradual passband rolloff with minimal stop band ripple

33. - E7D03

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

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

34. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

Select	Answer
A	To remove third-order distortion products
B	For higher efficiency
C	For compatibility with transmitters using phase modulation
D	To reduce impulse noise reception

35. - E7F13

What is the function of taps in a digital signal processing filter?

Select	Answer
A	Select the point at which baseband signals are generated
B	Provide access for debugging software
C	Provide incremental signal delays for filter algorithms
D	To reduce excess signal pressure levels

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	47
B	0.21
C	94
D	24

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

Select	Answer
A	NP0 capacitors
B	Toroidal inductors
C	Non-inductive resistors
D	Wirewound resistors

38. - E8A13

Which of these methods is commonly used to convert analog signals to digital signals?

Select	Answer
A	Sequential sampling
B	Level shifting
C	Phase reversal
D	Harmonic regeneration

39. - E8B02

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

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

40. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	Baud is twice the symbol rate
B	Baud is only used for RTTY
C	Symbol rate is only used for packet-based modes
D	They are the same

41. - E8D04

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

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

42. - E9A13

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 12 dB gain over an isotropic antenna?

Select	Answer
A	12.5 dB
B	14.15 dB
C	9.85 dB
D	6.17 dB

43. - E9B10

What is the principle of a Method of Moments analysis?

Select	Answer
A	A wire is modeled as a series of points, each having a distinct location in space
B	A wire is modeled as a series of segments, each having a distinct value of voltage across it
C	A wire is modeled as a single sine-wave current generator
D	A wire is modeled as a series of segments, each having a uniform value of current

44. - E9C06

What is the effect of a terminating resistor on a rhombic antenna?

Select	Answer
A	It decreases the ground loss
B	It changes the radiation pattern from horizontal to vertical polarization
C	It reflects the standing waves on the antenna elements back to the transmitter
D	It changes the radiation pattern from bidirectional to unidirectional

45. - 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 collinear to each other with the driven elements fed 180 degrees out of phase
D	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase

46. - E9E10

Which of these choices is an effective way to match an antenna with a 100 ohm feed point impedance to a 50 ohm coaxial cable feed line?

Select	Answer
A	Connect a 1/4-wavelength open stub of 300 ohm twin-lead in parallel with the coaxial feed line where it connects to the antenna
B	Connect 1/2 wavelength shorted stub of 75 ohm cable in parallel with the 50 ohm cable where it attaches to the antenna
C	Insert a 1/2 wavelength piece of 300 ohm twin-lead in series between the antenna terminals and the 50 ohm feed cable
D	Insert a 1/4-wavelength piece of 75 ohm coaxial cable transmission line in series between the antenna terminals and the 50 ohm feed cable

47. - E9F11

What impedance does a 1/8 wavelength transmission line present to a generator when the line is open at the far end?

Select	Answer
A	The same as the characteristic impedance of the line
B	The same as the input impedance of the final generator stage
C	A capacitive reactance
D	An inductive reactance

48. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Radio propagation
B	Impedance along transmission lines
C	Radiation resistance
D	Antenna radiation pattern

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

Select	Answer
A	A vertical antenna coupled to a feed line through an inductive loop of wire
B	A small coil of wire tightly wound around a toroidal ferrite core
C	One or more turns of wire wound in the shape of a large open coil
D	A large circularly polarized antenna

50. - E0A05

What is one of the potential hazards of using microwaves in the amateur radio bands?

Select	Answer
A	The high gain antennas commonly used can result in high exposure levels
B	Microwaves are ionizing radiation
C	Microwaves often travel long distances by ionospheric reflection
D	The extremely high frequency energy can damage the joints of antenna structures

Figure E6-2

Figure E6-3

Figure E7-4