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

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1. - 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

2. - E1B11

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHZ?

Select	Answer
A	At least 73 dB below
B	At least 63 dB below
C	At least 43 dB below
D	At least 53 dB below

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	Communications incidental to the purpose of the amateur service and remarks of a personal nature
B	Business-related messages for non-profit organizations
C	Messages intended for connection to users of the maritime satellite service
D	All of these choices are correct

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	Any amateur station so designated by the ITU
B	Any amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator
C	All of these choices are correct
D	Any amateur station designated by NASA

5. - E1E03

What is a Volunteer Examiner Coordinator?

Select	Answer
A	The person who has entered into an agreement with the FCC to be the VE session manager
B	A person who has volunteered to administer amateur operator license examinations
C	A person who has volunteered to prepare amateur operator license examinations
D	An organization that has entered into an agreement with the FCC to coordinate amateur operator license examinations

6. - E1F06

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

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

7. - E2A08

Why should effective radiated power to a satellite which uses a linear transponder be limited?

Select	Answer
A	To avoid reducing the downlink power to all other users
B	To prevent creating errors in the satellite telemetry
C	To prevent the satellite from emitting out-of-band signals
D	To avoid interfering with terrestrial QSOs

8. - E2B17

What is the approximate bandwidth of a slow-scan TV signal?

Select	Answer
A	3 kHz
B	6 MHz
C	600 Hz
D	2 MHz

9. - E2C13

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control where the transmitter is located in the U.S.?

Select	Answer
A	/ followed by the USPS two letter abbreviation for the state in which the remote station is located
B	The ARRL section of the remote station
C	No additional indicator is required
D	/R# where # is the district of the remote station

10. - E2D05

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

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

11. - E2E13

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

12. - E3A06

Which of the following is required for microwave propagation via rain scatter?

Select	Answer
A	Rain droplets must be within the E layer
B	Rain droplets must be electrically charged
C	All of these choices are correct
D	The rain must be within radio range of both stations

13. - E3B11

At what time of day is Sporadic-E propagation most likely to occur?

Select	Answer
A	Early evening
B	Around sunset
C	Any time
D	Around sunrise

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. - E4A01

Which of the following parameter determines the bandwidth of a digital or computer-based oscilloscope?

Select	Answer
A	Sample resolution
B	Input impedance
C	Sampling rate
D	Input capacitance

16. - E4B14

What happens if a dip meter is too tightly coupled to a tuned circuit being checked?

Select	Answer
A	A less accurate reading results
B	Cross modulation occurs
C	Harmonics are generated
D	Intermodulation distortion occurs

17. - E4C07

What does the MDS of a receiver represent?

Select	Answer
A	The meter display sensitivity
B	The multiplex distortion stability
C	The minimum discernible signal
D	The maximum detectable spectrum

18. - E4D11

Why are third-order intermodulation products created within a receiver of particular interest compared to other products?

Select	Answer
A	The third-order product of two signals which are in the band of interest is also likely to be within the band
B	Third-order products are an indication of poor image rejection
C	The third-order intercept is much higher than other orders
D	Third-order intermodulation produces three products for every input signal within the band of interest

19. - E4E01

Which of the following types of receiver noise can often be reduced by use of a receiver noise blanker?

Select	Answer
A	Ignition noise
B	Broadband white noise
C	All of these choices are correct
D	Heterodyne interference

20. - E5A05

What is the magnitude of the current at the input of a series RLC circuit as the frequency goes through resonance?

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

21. - E5B10

What is the relationship between the current through an inductor and the voltage across an inductor?

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

22. - E5C10

When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?

Select	Answer
A	The difference between the resistive and reactive components
B	Resistive component
C	Reactive component
D	The sum of the reactive and resistive components

23. - E5D11

What is the power factor of an R-L circuit having a 60 degree phase angle between the voltage and the current?

Select	Answer
A	1.73
B	1.414
C	0.866
D	0.5

24. - E6A15

Which semiconductor material contains excess holes in the outer shell of electrons?

Select	Answer
A	N-type
B	Bipolar-type
C	P-type
D	Superconductor-type

25. - E6B08

Which of the following describes a type of semiconductor diode?

Select	Answer
A	CMOS-field effect
B	Thermionic emission diode
C	Electrolytic rectifier
D	Metal-semiconductor junction

26. - E6C01

What is the function of hysteresis in a comparator?

Select	Answer
A	To increase the sensitivity
B	To cause the output to change states continually
C	To prevent input noise from causing unstable output signals
D	To allow the comparator to be used with AC input signal

27. - E6D14

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

Select	Answer
A	Ferrite
B	Brass
C	Powdered-iron
D	Ceramic

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

Select	Answer
A	Point-to-point construction
B	Microstrip construction
C	Ground-plane construction
D	Wave-soldering construction

29. - E6F04

What is the photovoltaic effect?

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

30. - E7A11

What type of logic defines "1" as a high voltage?

Select	Answer
A	Positive Logic
B	Reverse Logic
C	Assertive Logic
D	Negative logic

31. - E7B15

What is one way to prevent thermal runaway in a bipolar transistor amplifier?

Select	Answer
A	Use a resistor in series with the emitter
B	Neutralization
C	Select transistors with high beta
D	All of these choices are correct

32. - E7C07

What kind of filter would you use to attenuate an interfering carrier signal while receiving an SSB transmission?

Select	Answer
A	A band-pass filter
B	An all-pass filter
C	A notch filter
D	A Pi-network filter

33. - E7D15

What is the purpose of a "step-start" circuit in a high voltage power supply?

Select	Answer
A	To allow the filter capacitors to charge gradually
B	To allow for remote control of the power supply
C	To compensate for variations of the incoming line voltage
D	To provide a dual-voltage output for reduced power applications

34. - E7E11

Which type of detector is used for demodulating SSB signals?

Select	Answer
A	Product detector
B	Phase comparator
C	Phase detector
D	Discriminator

35. - E7F11

What sets the minimum detectable signal level for an SDR in the absence of atmospheric or thermal noise?

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

36. - E7G04

What is meant by the term op-amp input offset voltage?

Select	Answer
A	The difference between the output voltage of the op-amp and the input voltage required in the immediately following stage
B	The differential input voltage needed to bring the open loop output voltage to zero
C	The output voltage of the op-amp minus its input voltage
D	The potential between the amplifier input terminals of the op-amp in an open loop condition

37. - E7H06

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

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

38. - E8A09

How many levels can an analog-to-digital converter with 8 bit resolution encode?

Select	Answer
A	256
B	8
C	256 divided by the gain of the input amplifier
D	8 multiplied by the gain of the input amplifier

39. - 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	3
B	2000
C	6000
D	1/3

40. - E8C04

What technique is used to minimize the bandwidth requirements of a PSK31 signal?

Select	Answer
A	Use of trapezoidal data pulses
B	Use of sinusoidal data pulses
C	Reed-Solomon character encoding
D	Zero-sum character encoding

41. - E8D01

Why are received spread spectrum signals resistant to interference?

Select	Answer
A	The receiver is always equipped with a digital blanker
B	The high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
C	Signals not using the spread spectrum algorithm are suppressed in the receiver
D	If interference is detected by the receiver it will signal the transmitter to change frequencies

42. - E9A12

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 6 dB gain over an isotropic antenna?

Select	Answer
A	6.0 dB
B	8.15 dB
C	3.85 dB
D	2.79 dB

43. - E9B03

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

Select	Answer
A	14 dB
B	18 dB
C	12 dB
D	24 dB

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

Select	Answer
A	It changes the impedance angle of the matching network
B	It reduces low-angle radiation
C	It reduces losses in the radiating portion of the antenna
D	It causes increased SWR

45. - E9D08

What happens as the Q of an antenna increases?

Select	Answer
A	Gain is reduced
B	SWR bandwidth increases
C	SWR bandwidth decreases
D	More common-mode current is present on the feed line

46. - E9E07

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

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

47. - E9F09

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 7.2 MHz?

Select	Answer
A	10 meters
B	24 meters
C	6.9 meters
D	50 meters

48. - E9G03

Which of the following is often determined using a Smith chart?

Select	Answer
A	Beam headings and radiation patterns
B	Trigonometric functions
C	Satellite azimuth and elevation bearings
D	Impedance and SWR values in transmission lines

49. - E9H05

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

Select	Answer
A	It has a bidirectional pattern
B	It is practical for use only on VHF bands
C	It is non-rotatable
D	It receives equally well in all directions

50. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

Select	Answer
A	Ingestion of ozone gas from the cooling system
B	Localized heating of the body from RF exposure in excess of the MPE limits
C	Hearing loss caused by high voltage corona discharge
D	Blood clotting from the intense magnetic field

Figure E9-1