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

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1. - E1A10

If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?

Select	Answer
A	Its operation must be approved by the master of the ship or the pilot in command of the aircraft
B	The amateur station must have a power supply that is completely independent of the main ship or aircraft power supply
C	The amateur operator must have an FCC Marine or Aircraft endorsement on his or her amateur license
D	The amateur station operator must agree not to transmit when the main radio of the ship or aircraft is in use

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

3. - E1C07

What is meant by local control?

Select	Answer
A	Automatically manipulating local station controls
B	Direct manipulation of the transmitter by a control operator
C	Controlling a station through a local auxiliary link
D	Controlling a repeater using a portable handheld transceiver

4. - E1D03

What is a telecommand station in the amateur satellite service?

Select	Answer
A	An amateur station located more than 50 km above the Earth's surface
B	An amateur station that transmits telemetry consisting of measurements of upper atmosphere
C	An amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites
D	An amateur station that transmits communications to initiate, modify or terminate functions of a space station

5. - E1E10

What must the administering VEs do after the administration of a successful examination for an amateur operator license?

Select	Answer
A	They must collect and send the documents to the FCC according to instructions
B	They must collect and send the documents to the NCVEC for grading
C	They must collect and submit the documents to the coordinating VEC for grading
D	They must submit the application document to the coordinating VEC according to the coordinating VEC instructions

6. - 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	420 MHz - 430 MHz
B	440 MHz - 450 MHz
C	222 MHz - 223 MHz
D	53 MHz - 54 MHz

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

Select	Answer
A	Radar
B	Doppler shift of beacon signals
C	Bandwidth compressed LORAN
D	APRS

8. - E2B16

Which is a video standard used by North American Fast Scan ATV stations?

Select	Answer
A	PAL
B	DRM
C	Scottie
D	NTSC

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	/R# where # is the district of the remote station
C	No additional indicator is required
D	The ARRL section of the remote station

10. - E2D09

Which of these digital modes has the fastest data throughput under clear communication conditions?

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

11. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Audio FSK has a superior frequency response
B	Direct FSK applies the data signal to the transmitter VFO
C	Audio FSK can be performed anywhere in the transmit chain
D	Direct FSK uses a DC-coupled data connection

12. - E3A16

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

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

13. - E3B01

What is transequatorial propagation?

Select	Answer
A	Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
B	Propagation between any two points located on the magnetic equator
C	Propagation between two continents by way of ducts along the magnetic equator
D	Propagation between two stations at the same latitude

14. - E3C13

What type of polarization is best for ground-wave propagation?

Select	Answer
A	Vertical
B	Horizontal
C	Circular
D	Elliptical

15. - E4A01

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

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

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

Select	Answer
A	High impedance input
B	Low reluctance input
C	High reluctance input
D	Low impedance input

17. - E4C11

Which of the following is a desirable amount of selectivity for an amateur SSB phone receiver?

Select	Answer
A	1 kHz
B	4.8 kHz
C	2.4 kHz
D	4.2 kHz

18. - E4D06

What is the term for unwanted signals generated by the mixing of two or more signals?

Select	Answer
A	Amplifier desensitization
B	Intermodulation interference
C	Adjacent channel interference
D	Neutralization

19. - E4E14

What is one type of electrical interference that might be caused by the operation of a nearby personal computer?

Select	Answer
A	A clicking noise at intervals of a few seconds
B	The appearance of unstable modulated or unmodulated signals at specific frequencies
C	A loud AC hum in the audio output of your station receiver
D	A whining type noise that continually pulses off and on

20. - E5A02

What is resonance in an electrical circuit?

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

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

Select	Answer
A	55 seconds
B	220 seconds
C	440 seconds
D	110 seconds

22. - E5C07

What is a vector?

Select	Answer
A	The inverse of the sine function
B	A quantity with both magnitude and an angular component
C	The inverse of the tangent function
D	The value of a quantity that changes over time

23. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

Select	Answer
A	It is dissipated in the formation of inductive and capacitive fields
B	It is dissipated as kinetic energy in the circuit
C	It is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
D	It is dissipated as heat in the circuit

24. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

Select	Answer
A	Alpha rejection frequency
B	Corner frequency
C	Alpha cutoff frequency
D	Beta cutoff frequency

25. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch or attenuator?

Select	Answer
A	Reverse bias controls its forward voltage drop
B	Ability to dissipate large amounts of power
C	A large region of intrinsic material
D	Extremely high reverse breakdown voltage

26. - E6C01

What is the function of hysteresis in a comparator?

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

27. - E6D13

What is the primary cause of inductor self-resonance?

Select	Answer
A	The skin effect
B	Inter-turn capacitance
C	Non-linear core hysteresis
D	Inductive kickback

28. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	DIP
B	Ball grid array
C	SOT
D	PLCC

29. - E6F12

What absorbs the energy from light falling on a photovoltaic cell?

Select	Answer
A	Protons
B	Holes
C	Electrons
D	Photons

30. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

Select	Answer
A	An OR gate
B	A multiplexer
C	An XOR gate
D	A flip-flop

31. - E7B01

For what portion of a signal cycle does a Class AB amplifier operate?

Select	Answer
A	More than 180 degrees but less than 360 degrees
B	The entire cycle
C	Less than 180 degrees
D	Exactly 180 degrees

32. - E7C13

What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?

Select	Answer
A	L-networks cannot perform impedance transformation
B	Pi-networks have fewer components
C	Pi-networks are designed for balanced input and output
D	The Q of Pi-networks can be varied depending on the component values chosen

33. - 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	Matching of day and night charge rates
D	Control of electrolyte levels during battery discharge

34. - E7E06

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

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

35. - E7F13

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

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

36. - E7G06

Which of the following is the most appropriate use of an op-amp active filter?

Select	Answer
A	As an audio filter in a receiver
B	For smoothing power supply output
C	As a low-pass filter used between a transmitter and a transmission line
D	As a high-pass filter used to block RFI at the input to receivers

37. - E7H08

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

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

38. - E8A09

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

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

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A frequency modulation technique which uses non-harmonically related frequencies
B	A digital mode for narrow band, slow speed transmissions
C	A bandwidth compression technique using Fourier transforms
D	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference

40. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By the receiving station repeating each block of three data characters
B	By transmitting a special algorithm to the receiving station along with the data characters
C	By transmitting extra data that may be used to detect and correct transmission errors
D	By varying the frequency shift of the transmitted signal according to a predefined algorithm

41. - E8D01

Why are received spread spectrum signals resistant to interference?

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

42. - 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	Distance from the transmitter
B	Soil conductivity
C	Take-off angle
D	The standing wave ratio

43. - E9B10

What is the principle of a Method of Moments analysis?

Select	Answer
A	A wire is modeled as a series of segments, each having a uniform value of current
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 points, each having a distinct location in space

44. - E9C04

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

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

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Higher losses
B	Lower Q
C	Greater structural strength
D	Improved radiation efficiency

46. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

Select	Answer
A	The gamma match
B	The delta match
C	The stub match
D	The epsilon match

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	50 meters
B	24 meters
C	6.9 meters
D	10 meters

48. - E9G05

What type of chart is shown in Figure E9-3?

Select	Answer
A	Azimuth angle radiation pattern chart
B	Free space radiation directivity chart
C	Smith chart
D	Elevation angle radiation pattern chart

49. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

Select	Answer
A	It must be mounted more than 1 wavelength above ground
B	It should be one or more wavelengths long
C	It should be configured as a four-sided loop
D	Its overall length must not exceed 1/4 wavelength

50. - E0A07

How may dangerous levels of carbon monoxide from an emergency generator be detected?

Select	Answer
A	By the yellowish appearance of the gas
B	By the odor
C	Only with a carbon monoxide detector
D	Any ordinary smoke detector can be used

Figure E9-3