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

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E1A07

Which amateur band requires transmission on specific channels rather than on a range of frequencies?

Select	Answer
A	17 meter band
B	60 meter band
C	12 meter band
D	30 meter band

2. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historical Places?

Select	Answer
A	A form FSD-15 must be submitted to the Department of the Interior
B	A letter of intent must be filed with the National Audubon Society
C	A proposal must be submitted to the National Park Service
D	An Environmental Assessment must be submitted to the FCC

3. - E1C07

What is meant by local control?

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

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	All of these choices are correct
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	Any amateur station so designated by the ITU
D	Any amateur station designated by NASA

5. - E1E03

What is a Volunteer Examiner Coordinator?

Select	Answer
A	A person who has volunteered to prepare amateur operator license examinations
B	The person who has entered into an agreement with the FCC to be the VE session manager
C	An organization that has entered into an agreement with the FCC to coordinate amateur operator license examinations
D	A person who has volunteered to administer 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 additional spectrum for personal use
B	To provide temporary operation while awaiting normal licensing
C	To allow regular operation on Land Mobile channels
D	To provide for experimental amateur communications

7. - E2A10

Why may the received signal from an amateur satellite exhibit a rapidly repeating fading effect?

Select	Answer
A	Because of the satellite's low orbital altitude
B	Because the satellite is spinning
C	Because of ionospheric absorption
D	Because of the Doppler Effect

8. - E2B08

Which of the following is a common method of transmitting accompanying audio with amateur fast-scan television?

Select	Answer
A	All of these choices are correct
B	Frequency modulation of the video carrier
C	A separate VHF or UHF audio link
D	Frequency-modulated sub-carrier

9. - E2C10

Why might a DX station state that they are listening on another frequency?

Select	Answer
A	All of these choices are correct
B	To improve operating efficiency by reducing interference
C	To separate the calling stations from the DX station
D	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations

10. - E2D11

Which of the following data are used by the APRS network to communicate your location?

Select	Answer
A	Time and frequency
B	Radio direction finding spectrum analysis
C	Latitude and longitude
D	Polar coordinates

11. - E2E06

What is the most common data rate used for HF packet?

Select	Answer
A	1200 baud
B	110 baud
C	300 baud
D	48 baud

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	Electric and magnetic fields become aligned as they travel
C	The energy propagates through a medium with a high refractive index
D	Changing electric and magnetic fields propagate the energy

13. - E3B01

What is transequatorial propagation?

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

14. - E3C05

What orientation of Bz (B sub z) increases the likelihood that incoming particles from the Sun will cause disturbed conditions?

Select	Answer
A	Westward
B	Northward
C	Southward
D	Eastward

15. - E4A05

What might be an advantage of a digital vs an analog oscilloscope?

Select	Answer
A	Manipulation of time base after trace capture
B	Automatic amplitude and frequency numerical readout
C	All of these choices are correct
D	Storage of traces for future reference

16. - E4B03

If a frequency counter with a specified accuracy of +/- 1.0 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	165.2 Hz
B	1.4652 MHz
C	14.652 kHz
D	146.52 Hz

17. - E4C16

Which of the following is caused by missing codes in an SDR receiver's analog-to-digital converter?

Select	Answer
A	Loss of sensitivity
B	Excess output level
C	Overload
D	Distortion

18. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

Select	Answer
A	A Class D final amplifier
B	A band-pass filter in the feed line between the transmitter and receiver
C	A properly terminated circulator at the output of the transmitter
D	A Class C final amplifier

19. - E4E09

What undesirable effect can occur when using an IF noise blanker?

Select	Answer
A	FM signals can no longer be demodulated
B	The audio frequency bandwidth of the received signal might be compressed
C	Nearby signals may appear to be excessively wide even if they meet emission standards
D	Received audio in the speech range might have an echo effect

20. - E5A11

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

Select	Answer
A	157.8 Hz
B	47.3 kHz
C	23.67 kHz
D	315.6 Hz

21. - E5B02

What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

Select	Answer
A	One time constant
B	One discharge period
C	A discharge factor of one
D	An exponential discharge rate of one

22. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

Select	Answer
A	A negative real part
B	A positive phase angle
C	A negative phase angle
D	A positive real part

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 as heat in the circuit
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 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 very low frequency RF circuits
B	In high-power audio circuits
C	In high-current rectifier circuits
D	In microwave circuits

25. - E6B06

Which of the following is a common use of a hot-carrier diode?

Select	Answer
A	As a constant voltage reference in a power supply
B	As a VHF/UHF mixer or detector
C	As balanced mixers in FM generation
D	As a variable capacitance in an automatic frequency control circuit

26. - E6C14

What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?

Select	Answer
A	All of these choices are correct
B	Many similar gates are less expensive than a mixture of gate types
C	A PGA contains its own internal power supply
D	Complex logic functions can be created in a single integrated circuit

27. - E6D08

What is one reason for using powdered-iron cores rather than ferrite cores in an inductor?

Select	Answer
A	Powdered-iron cores generally have greater initial permeability
B	Powdered-iron cores generally maintain their characteristics at higher currents
C	Powdered-iron cores use smaller diameter wire for the same inductance
D	Powdered-iron cores generally require fewer turns to produce a given inductance

28. - E6E01

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

Select	Answer
A	Its phase shift changes rapidly with frequency
B	It is used in a battery charger circuit
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. - E6F11

What is the approximate open-circuit voltage produced by a fully-illuminated silicon photovoltaic cell?

Select	Answer
A	0.1 V
B	0.5 V
C	12 V
D	1.5 V

30. - E7A07

What logical operation does a NAND gate perform?

Select	Answer
A	It produces logic "0" at its output if some but not all inputs are logic "1"
B	It produces logic "1" at its output only when all inputs are logic "1"
C	It produces logic "0" at its output only when all inputs are logic "0"
D	It produces logic "0" at its output only when all inputs are logic "1"

31. - E7B07

Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?

Select	Answer
A	Signal inversion
B	Reduced intermodulation products
C	Increased overall intelligibility
D	Signal distortion and excessive bandwidth

32. - E7C14

Which mode is most affected by non-linear phase response in a receiver IF filter?

Select	Answer
A	Video
B	Digital
C	Single-Sideband voice
D	Meteor scatter

33. - E7D14

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

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

34. - E7E06

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

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

35. - E7F12

What digital process is applied to I and Q signals in order to recover the baseband modulation information?

Select	Answer
A	Quadrature mixing
B	Fast Fourier Transform
C	Decimation
D	Signal conditioning

36. - E7G06

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

Select	Answer
A	For smoothing power supply output
B	As an audio filter in a receiver
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. - E7H04

How is positive feedback supplied in a Colpitts oscillator?

Select	Answer
A	Through a neutralizing capacitor
B	Through link coupling
C	Through a capacitive divider
D	Through a tapped coil

38. - E8A12

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

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

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 increases as the RF carrier frequency increases
C	It does not depend on the RF carrier frequency
D	It varies with the square root of the RF carrier frequency

40. - E8C07

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

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

41. - E8D05

What is the most common method of reducing key clicks?

Select	Answer
A	Increase keying waveform rise and fall times
B	Reduce keying waveform rise and fall times
C	Low-pass filters at the transmitter output
D	High-pass filters at the transmitter output

42. - E9A16

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

Select	Answer
A	126 watts
B	2000 watts
C	300 watts
D	317 watts

43. - E9B05

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

Select	Answer
A	Polarization
B	Elevation
C	Radiation resistance
D	Azimuth

44. - E9C01

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed 180 degrees out of phase?

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

45. - E9D04

Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?

Select	Answer
A	To minimize losses
B	To maximize losses
C	To minimize the Q
D	To swamp out harmonics

46. - E9E09

Which of these matching systems is an effective method of connecting a 50 ohm coaxial cable feed line to a grounded tower so it can be used as a vertical antenna?

Select	Answer
A	All of these choices are correct
B	Gamma match
C	Double-bazooka match
D	Hairpin 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	10 meters
B	6.9 meters
C	24 meters
D	50 meters

48. - E9G01

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

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

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 configured as a four-sided loop
C	Its overall length must not exceed 1/4 wavelength
D	It should be one or more wavelengths long

50. - E0A05

What is one of the potential hazards of using microwaves in the amateur radio bands?

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

Figure E9-2