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

2. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

Select	Answer
A	You may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules
B	You must file an Environmental Impact Statement with the EPA before construction begins
C	No special rules apply if your antenna structure will be less than 300 feet in height
D	You must obtain a construction permit from the airport zoning authority

3. - 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 there is no control operator
B	Under local control there is no control operator
C	Under automatic control the control operator is not required to be present at the control point
D	Under local control a control operator is not required to be present at a control point

4. - E1D06

Which of the following is a requirement of a space station?

Select	Answer
A	All of these choices are correct
B	The space station must be capable of changing its orbit whenever such a change is ordered by NASA
C	The space station must be capable of terminating transmissions by telecommand when directed by the FCC
D	The space station must cease all transmissions after 5 years

5. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

Select	Answer
A	Send the application form to the FCC and inform the FCC of the grade
B	Return the application document to the examinee
C	Destroy the application form
D	Maintain the application form with the VEC's records

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

Select	Answer
A	A station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
B	The transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions
C	All of these choices are correct
D	The transmission must not be used to obscure the meaning of any communication

7. - E2A03

What is the orbital period of an Earth satellite?

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

8. - E2B03

How is an interlaced scanning pattern generated in a fast-scan (NTSC) television system?

Select	Answer
A	By scanning lines from left to right in one field and right to left in the next
B	By scanning odd numbered lines in one field and even numbered lines in the next
C	By scanning each field from bottom to top
D	By scanning two fields simultaneously

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

10. - E2D01

Which of the following digital modes is especially designed for use for meteor scatter signals?

Select	Answer
A	Hellschreiber
B	WSPR
C	APRS
D	FSK441

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

Select	Answer
A	First Error Correction
B	Forward Error Correction
C	Fatal Error Correction
D	Final Error Correction

12. - E3A09

Which of the following frequency range is most suited for meteor scatter communications?

Select	Answer
A	28 MHz - 148 MHz
B	10 MHz - 14 MHz
C	220 MHz - 450 MHz
D	1.8 MHz - 1.9 MHz

13. - E3B06

Which of the following amateur bands most frequently provides long-path propagation?

Select	Answer
A	6 meters
B	20 meters
C	10 meters
D	80 meters

14. - E3C06

By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

Select	Answer
A	By approximately 50 percent of the distance
B	By approximately 15 percent of the distance
C	By approximately four times the distance
D	By approximately twice the distance

15. - E4A09

When using a computer's soundcard input to digitize signals, what is the highest frequency signal that can be digitized without aliasing?

Select	Answer
A	It depends on how the data is stored internally
B	The same as the sample rate
C	One-tenth the sample rate
D	One-half the sample rate

16. - E4B12

What is the significance of voltmeter sensitivity expressed in ohms per volt?

Select	Answer
A	The full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter
B	When used as a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test
C	When used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed
D	When used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit

17. - E4C07

What does the MDS of a receiver represent?

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

18. - E4D14

Which of the following is a way to reduce the likelihood of receiver desensitization?

Select	Answer
A	Raise the receiver IF frequency
B	Decrease the RF bandwidth of the receiver
C	Switch from fast AGC to slow AGC
D	Increase the receiver front end gain

19. - E4E13

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

Select	Answer
A	Arcing contacts in a thermostatically controlled device
B	A malfunctioning illuminated advertising display
C	All of these choices are correct
D	A defective doorbell or doorbell transformer inside a nearby residence

20. - E5A14

What is the resonant frequency of a series RLC circuit if R is 22 ohms, L is 50 microhenrys and C is 40 picofarads?

Select	Answer
A	3.56 MHz
B	1.78 MHz
C	44.72 MHz
D	22.36 MHz

21. - 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	68.2 degrees with the voltage lagging the current
B	68.2 degrees with the voltage leading the current
C	14.0 degrees with the voltage lagging the current
D	14.0 degrees with the voltage leading the current

22. - E5C11

What do the two numbers that are used to define a point on a graph using rectangular coordinates represent?

Select	Answer
A	The coordinate values along the horizontal and vertical axes
B	The tangent and cotangent values
C	The sine and cosine values
D	The magnitude and phase of the point

23. - E5D16

What is the power factor of an R-L circuit having a 30 degree phase angle between the voltage and the current?

Select	Answer
A	0.866
B	0.577
C	0.5
D	1.73

24. - E6A10

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

Select	Answer
A	2
B	6
C	4
D	5

25. - E6B12

What is one common use for PIN diodes?

Select	Answer
A	As a constant voltage source
B	As a constant current source
C	As an RF switch
D	As a high voltage rectifier

26. - E6C07

What best describes a pull-up or pull-down resistor?

Select	Answer
A	A resistor in a keying circuit used to reduce key clicks
B	A resistor connected to an op-amp output that only functions when the logic output is false
C	A resistor that insures that an oscillator frequency does not drive lower over time
D	A resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit

27. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

Select	Answer
A	Electrolytic capacitors
B	Steel-core toroids
C	Butterworth filters
D	Ferrite beads

28. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

Select	Answer
A	The ability to retrieve information from a single signal even in the presence of other strong signals
B	Plate current that is controlled by a control grid
C	Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range
D	Nearly infinite gain, very high input impedance, and very low output impedance

29. - E6F08

Why are optoisolators often used in conjunction with solid state circuits when switching 120VAC?

Select	Answer
A	Optoisolators provide a very high degree of electrical isolation between a control circuit and the circuit being switched
B	Optoisolators eliminate the effects of reflected light in the control circuit
C	Optoisolators provide impedance matching between the control circuit and power circuit
D	Optoisolators provide a low impedance link between a control circuit and a power circuit

30. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

Select	Answer
A	T flip-flop
B	Monostable multivibrator
C	Astable multivibrator
D	J-K flip-flop

31. - E7B14

Why are switching amplifiers more efficient than linear amplifiers?

Select	Answer
A	Linear amplifiers have high gain resulting in higher harmonic content
B	Switching amplifiers operate at higher voltages
C	Switching amplifiers use push-pull circuits
D	The power transistor is at saturation or cut off most of the time, resulting in low power dissipation

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

Select	Answer
A	Pi
B	Pi-L
C	Cascode
D	Omega

33. - E7D14

What is one purpose of a "bleeder" resistor in a conventional unregulated power supply?

Select	Answer
A	To improve output voltage regulation
B	To boost the amount of output current
C	To cut down on waste heat generated by the power supply
D	To balance the low-voltage filament windings

34. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

Select	Answer
A	Mixer blanking occurs
B	Automatic limiting occurs
C	Spurious mixer products are generated
D	A beat frequency is generated

35. - E7F16

How might the sampling rate of an existing digital signal be adjusted by a factor of 3/4?

Select	Answer
A	Interpolate by a factor of three, then decimate by a factor of four
B	Change the gain by a factor of 3/4
C	Multiply each sample value by a factor of 3/4
D	Add 3 to each input value and subtract 4 from each output value

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	94
B	47
C	0.21
D	24

37. - E7H02

Which describes a microphonic?

Select	Answer
A	Changes in oscillator frequency due to mechanical vibration
B	An IC used for amplifying microphone signals
C	Distortion caused by RF pickup on the microphone cable
D	Excess loading of the microphone by an oscillator

38. - E8A02

What type of wave has a rise time significantly faster than its fall time (or vice versa)?

Select	Answer
A	A cosine wave
B	A sine wave
C	A square wave
D	A sawtooth wave

39. - E8B02

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

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

40. - E8C05

What is the necessary bandwidth of a 13-WPM international Morse code transmission?

Select	Answer
A	Approximately 104 Hz
B	Approximately 13 Hz
C	Approximately 52 Hz
D	Approximately 26 Hz

41. - E8D02

What spread spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?

Select	Answer
A	Direct sequence
B	Frequency hopping
C	Phase compandored spread spectrum
D	Binary phase-shift keying

42. - E9A08

What is meant by antenna bandwidth?

Select	Answer
A	Antenna length divided by the number of elements
B	The angle formed between two imaginary lines drawn through the element ends
C	The angle between the half-power radiation points
D	The frequency range over which an antenna satisfies a performance requirement

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

Select	Answer
A	Polarization
B	Azimuth
C	Radiation resistance
D	Elevation

44. - E9C02

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

Select	Answer
A	A figure-8 broadside to the axis of the array
B	A figure-8 end-fire along the axis of the array
C	Cardioid
D	Omni-directional

45. - E9D12

Which of the following would provide the best RF ground for your station?

Select	Answer
A	An electrically short connection to a metal water pipe
B	An electrically short connection to 3 or 4 interconnected ground rods via a series RF choke
C	An electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
D	A 50 ohm resistor connected to ground

46. - E9E05

How must the driven element in a 3-element Yagi be tuned to use a hairpin matching system?

Select	Answer
A	The driven element resonance must be lower than the operating frequency
B	The driven element reactance must be capacitive
C	The driven element reactance must be inductive
D	The driven element radiation resistance must be higher than the characteristic impedance of the transmission line

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	24 meters
B	10 meters
C	6.9 meters
D	50 meters

48. - E9G01

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

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

49. - E9H10

How can the output voltage of a multiple turn receiving loop antenna be increased?

Select	Answer
A	By increasing either the number of wire turns in the loop or the area of the loop structure or both
B	By reducing the permeability of the loop shield
C	By increasing the number of wire turns in the loop and reducing the area of the loop structure
D	By winding adjacent turns in opposing directions

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Beryllium Oxide
B	Mica
C	Zinc oxide
D	Uranium Hexafluoride

Figure E6-2

Figure E7-4

Figure E9-2