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

2. - E1B09

Which amateur stations may be operated under RACES rules?

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

3. - E1C12

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

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

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

Select	Answer
A	6 meters, 2 meters, and 1.25 meters
B	6 meters and 2 meters
C	2 meters
D	2 meters and 1.25 meters

5. - E1E06

Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

Select	Answer
A	Each administering VE
B	The VEC coordinating the session
C	The FCC
D	The VE session manager

6. - E1F10

What is the maximum permitted transmitter peak envelope power for an amateur station transmitting spread spectrum communications?

Select	Answer
A	1.5 kW
B	1 W
C	1.5 W
D	10 W

7. - E2A03

What is the orbital period of an Earth satellite?

Select	Answer
A	The time it takes for a satellite to complete one revolution around the Earth
B	The time it takes for a satellite to travel from perigee to apogee
C	The point of minimum height of a satellite's orbit
D	The point of maximum height of a satellite's orbit

8. - E2B06

What is vestigial sideband modulation?

Select	Answer
A	Amplitude modulation in which one complete sideband and a portion of the other are transmitted
B	Spread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation
C	Narrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier
D	A type of modulation in which one sideband is inverted

9. - E2C08

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

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

10. - E2D04

What is the purpose of digital store-and-forward functions on an Amateur Radio satellite?

Select	Answer
A	To upload operational software for the transponder
B	To store digital messages in the satellite for later download by other stations
C	To relay messages between satellites
D	To delay download of telemetry between satellites

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

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

12. - E3A14

From the contiguous 48 states, in which approximate direction should an antenna be pointed to take maximum advantage of aurora propagation?

Select	Answer
A	East
B	North
C	South
D	West

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 become phase-locked
C	They are bent toward the magnetic poles
D	Their polarization is randomly modified

14. - E3C07

Which of the following descriptors indicates the greatest solar flare intensity?

Select	Answer
A	Class A
B	Class X
C	Class M
D	Class B

15. - E4A04

What determines the upper frequency limit for a computer soundcard-based oscilloscope program?

Select	Answer
A	All of these choices are correct
B	Q of the interface of the interface circuit
C	Amount of memory on the soundcard
D	Analog-to-digital conversion speed of the soundcard

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	Intermodulation distortion occurs
C	Harmonics are generated
D	Cross modulation occurs

17. - E4C06

A CW receiver with the AGC off has an equivalent input noise power density of -174 dBm/Hz. What would be the level of an unmodulated carrier input to this receiver that would yield an audio output SNR of 0 dB in a 400 Hz noise bandwidth?

Select	Answer
A	-174 dBm
B	-148 dBm
C	-155 dBm
D	-164 dBm

18. - E4D01

What is meant by the blocking dynamic range of a receiver?

Select	Answer
A	The minimum difference in dB between the levels of two FM signals which will cause one signal to block the other
B	The difference in dB between the noise floor and the level of an incoming signal which will cause 1 dB of gain compression
C	The difference in dB between the noise floor and the third order intercept point
D	The minimum difference in dB between two signals which produce third order intermodulation products greater than the noise floor

19. - E4E07

How can you determine if line noise interference is being generated within your home?

Select	Answer
A	By observing the AC power line waveform with an oscilloscope
B	By checking the power line voltage with a time domain reflectometer
C	By turning off the AC power line main circuit breaker and listening on a battery operated radio
D	By observing the AC power line voltage with a spectrum analyzer

20. - E5A12

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

Select	Answer
A	15.7 kHz
B	436.6 kHz
C	31.4 kHz
D	218.3 kHz

21. - E5B06

What is susceptance?

Select	Answer
A	The magnetic impedance of a circuit
B	The inverse of reactance
C	A measure of the efficiency of a transformer
D	The ratio of magnetic field to electric field

22. - E5C06

What does the impedance 50-j25 represent?

Select	Answer
A	25 ohms resistance in series with 50 ohms inductive reactance
B	25 ohms resistance in series with 50 ohms capacitive reactance
C	50 ohms resistance in series with 25 ohms capacitive reactance
D	50 ohms resistance in series with 25 ohms inductive reactance

23. - E5D09

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

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

24. - E6A01

In what application is gallium arsenide used as a semiconductor material in preference to germanium or silicon?

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

25. - E6B13

What type of bias is required for an LED to emit light?

Select	Answer
A	Zero bias
B	Reverse bias
C	Inductive bias
D	Forward bias

26. - E6C03

What is tri-state logic?

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

27. - E6D16

What is the common name for a capacitor connected across a transformer secondary that is used to absorb transient voltage spikes?

Select	Answer
A	Trimmer capacitor
B	Clipper capacitor
C	Feedback capacitor
D	Snubber capacitor

28. - E6E01

Which of the following is true of a charge-coupled device (CCD)?

Select	Answer
A	It is used in a battery charger circuit
B	Its phase shift changes rapidly with frequency
C	It samples an analog signal and passes it in stages from the input to the output
D	It is a CMOS analog-to-digital converter

29. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

Select	Answer
A	Silicon
B	Cadmium Sulfide
C	Selenium
D	Copper oxide

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 "1" at its output if any single input is logic "1"
C	It produces logic "0" 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. - E7B16

What is the effect of intermodulation products in a linear power amplifier?

Select	Answer
A	Transmission of spurious signals
B	Low efficiency
C	Creation of parasitic oscillations
D	All of these choices are correct

32. - E7C08

Which of the following factors has the greatest effect in helping determine the bandwidth and response shape of a crystal ladder filter?

Select	Answer
A	The gain of the RF stage preceding the filter
B	The DC voltage applied to the quartz crystal
C	The amplitude of the signals passing through the filter
D	The relative frequencies of the individual crystals

33. - E7D10

What is the primary reason that a high-frequency switching type high voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

Select	Answer
A	It uses a large power factor compensation capacitor to create free power from the unused portion of the AC cycle
B	It uses a diode bridge rectifier for increased output
C	The inverter design does not require any output filtering
D	The high frequency inverter design uses much smaller transformers and filter components for an equivalent power output

34. - E7E07

What is meant by the term baseband in radio communications?

Select	Answer
A	The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
B	The frequency components present in the modulating signal
C	The unmodulated bandwidth of the transmitted signal
D	The lowest frequency band that the transmitter or receiver covers

35. - E7F08

What is the function of decimation with regard to digital filters?

Select	Answer
A	Reducing the effective sample rate by removing samples
B	Converting data to binary code decimal form
C	Attenuating the signal
D	Removing unnecessary significant digits

36. - E7G09

What will be the output voltage of the circuit shown in Figure E7-4 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

Select	Answer
A	0.23 volts
B	-2.3 volts
C	2.3 volts
D	-0.23 volts

37. - E7H10

What information is contained in the lookup table of a direct digital frequency synthesizer?

Select	Answer
A	The phase relationship between a voltage-controlled oscillator and the output waveform
B	The phase relationship between a reference oscillator and the output waveform
C	The amplitude values that represent a sine-wave output
D	The synthesizer frequency limits and frequency values stored in the radio memories

38. - E8A12

What is an advantage of using digital signals instead of analog signals to convey the same information?

Select	Answer
A	Less complex circuitry is required for digital signal generation and detection
B	Digital signals always occupy a narrower bandwidth
C	Digital signals can be regenerated multiple times without error
D	All of these choices are correct

39. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

Select	Answer
A	0.6
B	1.67
C	0.167
D	60

40. - E8C07

What is the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

Select	Answer
A	5.76 kHz
B	4.8 kHz
C	9.6 kHz
D	15.36 kHz

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

Select	Answer
A	Bit errors in the modem
B	Ground loops
C	Excessive numbers of retries
D	Excessive transmit audio levels

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

43. - E9B13

What does the abbreviation NEC stand for when applied to antenna modeling programs?

Select	Answer
A	Numerical Electromagnetic Code
B	Numeric Electrical Computation
C	National Electrical Code
D	Next Element Comparison

44. - E9C15

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with its height above ground?

Select	Answer
A	The horizontal beam width increases with height
B	The horizontal beam width decreases with height
C	The main lobe takeoff angle decreases with increasing height
D	The main lobe takeoff angle increases with increasing height

45. - E9D07

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

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

46. - E9E01

What system matches a higher impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

Select	Answer
A	The delta matching system
B	The stub matching system
C	The gamma matching system
D	The omega matching system

47. - E9F12

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

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

48. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The current axis
B	The voltage axis
C	The resistance axis
D	The reactance axis

49. - E9H06

What is the triangulation method of direction finding?

Select	Answer
A	The geometric angles of sky waves from the source are used to determine its position
B	Antenna headings from several different receiving locations are used to locate the signal source
C	A fixed receiving station plots three headings to the signal source
D	A fixed receiving station uses three different antennas to plot the location of the signal source

50. - E0A10

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

Select	Answer
A	Polymorphic silicon
B	Polyethylene
C	Polytetrafluroethylene
D	Polychlorinated Biphenyls

Figure E7-4

Figure E9-3