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

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1. - E0A05

What is one of the potential hazards of operating in the amateur radio microwave bands?

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

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

3. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

Select	Answer
A	All amateur service frequencies authorized to the control operator
B	Specific local government channels
C	Military Auxiliary Radio System (MARS) channels
D	Specific segments in the amateur service MF, HF, VHF and UHF bands

4. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

Select	Answer
A	Under automatic control the control operator is not required to be present at the control point
B	Under local control there is no control operator
C	Under automatic control there is no control operator
D	Under local control a control operator is not required to be present at a control point

5. - E1D02

Which of the following may transmit special codes intended to obscure the meaning of messages?

Select	Answer
A	Telecommand signals from a space telecommand station
B	Data containing personal information
C	Binary control characters
D	Auxiliary relay links carrying repeater audio

6. - E1E04

Which of the following best describes the Volunteer Examiner accreditation process?

Select	Answer
A	The prospective VE obtains accreditation from the FCC
B	Each General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
C	The procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner
D	The amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau

7. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

Select	Answer
A	222 MHz - 223 MHz
B	440 MHz - 450 MHz
C	420 MHz - 430 MHz
D	53 MHz - 54 MHz

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. - E2B08

What technique allows commercial analog TV receivers to be used for fast-scan TV operations on the 70 cm band?

Select	Answer
A	Using USB and demodulating the signal with a computer sound card
B	Using converted satellite TV dishes
C	Transmitting on channels shared with cable TV
D	Transmitting on the abandoned TV channel 2

10. - E2C07

What is the Cabrillo format?

Select	Answer
A	The most common set of contest rules
B	A method of exchanging information during a contest QSO
C	A standard for submission of electronic contest logs
D	The rules of order for meetings between contest sponsors

11. - E2D06

Which of the following describes a method of establishing EME contacts?

Select	Answer
A	Judging optimum transmission times by monitoring beacons reflected from the moon
B	Storing and forwarding digital messages
C	High-speed CW identification to avoid fading
D	Time synchronous transmissions alternately from each station

12. - E2E12

How do ALE stations establish contact?

Select	Answer
A	ALE radios send a constant tone code to establish a frequency for future use
B	ALE radios monitor an internet site for the frequency they are being paged on
C	ALE radios activate when they hear their signal echoed by back scatter
D	ALE constantly scans a list of frequencies, activating the radio when the designated call sign is received

13. - E3A12

What is the cause of auroral activity?

Select	Answer
A	The interaction in the F2 layer between the solar wind and the Van Allen belt
B	Meteor showers concentrated in the extreme northern and southern latitudes
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. - E3B12

What is the primary characteristic of chordal hop propagation?

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

15. - E3C01

What does the radio communication term "ray tracing" describe?

Select	Answer
A	Modeling a radio wave's path through the ionosphere
B	Determining the radiation pattern from an array of antennas
C	The process in which an electronic display presents a pattern
D	Evaluating high voltage sources for x-rays

16. - E4A04

How is the compensation of an oscilloscope probe typically adjusted?

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

17. - E4B07

What do the subscripts of S parameters represent?

Select	Answer
A	The relative time between measurements
B	Frequency order of the measurements
C	Relative quality of the data
D	The port or ports at which measurements are made

18. - E4C11

Why can an attenuator be used to reduce receiver overload on the lower frequency HF bands with little or no impact on signal-to-noise ratio?

Select	Answer
A	Atmospheric noise is generally greater than internally generated noise even after attenuation
B	The attenuator has a low-pass filter to increase the strength of lower frequency signals
C	Signals are attenuated separately from the noise
D	The attenuator has a noise filter to suppress interference

19. - E4D10

What does a third-order intercept level of 40 dBm mean with respect to receiver performance?

Select	Answer
A	A pair of 40 dBm input signals will theoretically generate a third-order intermodulation product that has the same output amplitude as either of the input signals
B	A pair of 1 mW input signals will produce a third-order intermodulation product that is 40 dB stronger than the input signal
C	Signals less than 40 dBm will not generate audible third-order intermodulation products
D	The receiver can tolerate signals up to 40 dB above the noise floor without producing third-order intermodulation products

20. - E4E02

Which of the following types of noise can often be reduced with a digital signal processing noise filter?

Select	Answer
A	Broadband white noise
B	All these choices are correct
C	Ignition noise
D	Power line noise

21. - E5A13

What is an effect of increasing Q in a series resonant circuit?

Select	Answer
A	Fewer components are needed for the same performance
B	Internal voltages increase
C	Parasitic effects are minimized
D	Phase shift can become uncontrolled

22. - E5B07

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

Select	Answer
A	14.0 degrees with the voltage lagging the current
B	68.2 degrees with the voltage leading the current
C	14.0 degrees with the voltage leading the current
D	68.2 degrees with the voltage lagging the current

23. - E5C07

Where is the impedance of a pure resistance plotted on rectangular coordinates?

Select	Answer
A	On a line through the origin, slanted at 45 degrees
B	On a horizontal line, offset vertically above the horizontal axis
C	On the vertical axis
D	On the horizontal axis

24. - E5D08

How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200VAC at 5 amperes?

Select	Answer
A	1600 watts
B	200 watts
C	1000 watts
D	600 watts

25. - E6A01

In what application is gallium arsenide used as a semiconductor material?

Select	Answer
A	In very low-frequency RF circuits
B	In high-power audio circuits
C	In high-current rectifier circuits
D	In microwave circuits

26. - E6B08

Which of the following is a Schottky barrier diode?

Select	Answer
A	Electrolytic rectifier
B	Thermionic emission diode
C	PIN junction
D	Metal-semiconductor junction

27. - E6C08

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

Select	Answer
A	4
B	1
C	3
D	2

28. - E6D11

Which type of core material decreases inductance when inserted into a coil?

Select	Answer
A	Ceramic
B	Powdered iron
C	Ferrite
D	Brass

29. - E6E09

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

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

30. - E6F04

What is the photovoltaic effect?

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

31. - E7A06

What is a characteristic of a monostable multivibrator?

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

32. - E7B03

Which of the following components form the output of a class D amplifier circuit?

Select	Answer
A	A temperature compensating load resistor to improve linearity
B	A high-pass filter to compensate for low gain at low frequencies
C	A low-pass filter to remove switching signal components
D	A matched load resistor to prevent damage by switching transients

33. - E7C06

What are the distinguishing features of an elliptical filter?

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

34. - E7D05

Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?

Select	Answer
A	A shunt regulator
B	A constant current source
C	A series regulator
D	A shunt current source

35. - E7E06

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

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

36. - E7F11

What sets the minimum detectable signal level for a direct-sampling SDR receiver in the absence of atmospheric or thermal noise?

Select	Answer
A	Missing codes and jitter
B	Sample clock phase noise
C	Reference voltage level and sample width in bits
D	Data storage transfer rate

37. - E7G02

What is ringing in a filter?

Select	Answer
A	A reduction in high frequency response
B	An echo caused by a long time delay
C	Partial cancellation of the signal over a range of frequencies
D	Undesired oscillations added to the desired signal

38. - E7H15

Which of these functions can be performed by a phase-locked loop?

Select	Answer
A	Frequency synthesis, FM demodulation
B	Photovoltaic conversion, optical coupling
C	Comparison of two digital input signals, digital pulse counter
D	Wide-band AF and RF power amplification

39. - E8A02

Which of the following is a type of analog-to-digital conversion?

Select	Answer
A	Phase reversal
B	Successive approximation
C	Harmonic regeneration
D	Level shifting

40. - E8B10

What is frequency division multiplexing?

Select	Answer
A	Two or more information streams are merged into a baseband, which then modulates the transmitter
B	The transmitted signal jumps from band to band at a predetermined rate
C	The transmitted signal is divided into packets of information
D	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter

41. - E8C09

Which digital code allows only one bit to change between sequential code values?

Select	Answer
A	Binary Coded Decimal Code
B	Excess 3 code
C	Extended Binary Coded Decimal Interchange Code
D	Gray code

42. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

Select	Answer
A	Baudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
B	Baudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
C	Baudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
D	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

43. - E9A11

Which of the following factors determines ground losses for a ground-mounted vertical antenna operating in the 3 MHz to 30 MHz range?

Select	Answer
A	The standing wave ratio
B	Take-off angle
C	Distance from the transmitter
D	Soil conductivity

44. - E9B02

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?

Select	Answer
A	18 dB
B	24 dB
C	14 dB
D	36 dB

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

46. - E9D11

Which of the following conductors would be best for minimizing losses in a station's RF ground system?

Select	Answer
A	Solid wire
B	Resistive wire, such as spark plug wire
C	Wide flat copper strap
D	Stranded wire

47. - E9E04

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

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

48. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically 1/2 wavelength long at 14.10 MHz?

Select	Answer
A	10.6 meters
B	8.5 meters
C	7.0 meters
D	13.3 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 impedance values with regard to the prime center
C	Reassigning reactance values with regard to the resistance axis
D	Reassigning prime center 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 has no clearly defined null
B	It is practical for use only on VHF and higher bands
C	It has a bidirectional pattern
D	All these choices are correct

Figure E6-3

Figure E9-1