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

2. - E1B01

Which of the following constitutes a spurious emission?

Select	Answer
A	A signal transmitted to prevent its detection by any station other than the intended recipient
B	Any transmitted signal that unintentionally interferes with another licensed radio station
C	An amateur station transmission made at random without the proper call sign identification
D	An emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted

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	Communications incidental to the purpose of the amateur service and remarks of a personal nature
C	Messages intended for connection to users of the maritime satellite service
D	Business-related messages for non-profit organizations

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

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

5. - E1E07

What should a VE do if a candidate fails to comply with the examiner's instructions during an amateur operator license examination?

Select	Answer
A	Allow the candidate to complete the examination, but invalidate the results
B	Warn the candidate that continued failure to comply will result in termination of the examination
C	Immediately terminate everyone's examination and close the session
D	Immediately terminate the candidate's examination

6. - E1F02

What privileges are authorized in the U.S. to persons holding an amateur service license granted by the Government of Canada?

Select	Answer
A	All privileges of the Extra Class license
B	The operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Extra Class privileges
C	None, they must obtain a U.S. license
D	Full privileges, up to and including those of the Extra Class License, on the 80, 40, 20, 15, and 10 meter bands

7. - E2A14

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

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

8. - E2B02

How many horizontal lines make up a fast-scan (NTSC) television frame?

Select	Answer
A	60
B	1080
C	525
D	30

9. - E2C04

What type of transmission is most often used for a ham radio mesh network?

Select	Answer
A	Multiple Frequency Shift Keying in the 10 GHz band
B	Store and forward on the 440 MHz band
C	Frequency division multiplex in the 24 GHz band
D	Spread spectrum in the 2.4 GHz band

10. - E2D14

What is one advantage of using JT65 coding?

Select	Answer
A	Permits fast-scan TV transmissions over narrow bandwidth
B	Uses only a 65 Hz bandwidth
C	The ability to decode signals which have a very low signal to noise ratio
D	Easily copied by ear if necessary

11. - E2E03

How is the timing of JT65 contacts organized?

Select	Answer
A	Stations take turns on alternate days
B	Alternating transmissions at 1 minute intervals
C	It depends on the lunar phase
D	By exchanging ACK/NAK packets

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	South
B	West
C	North
D	East

13. - E3B13

Why is chordal hop propagation desirable?

Select	Answer
A	Atmospheric noise is lower in the direction of chordal hop propagation
B	The signal experiences less loss along the path compared to normal skip propagation
C	The MUF for chordal hop propagation is much lower than for normal skip propagation
D	Signals travel faster along ionospheric chords

14. - E3C11

What does VOACAP software model?

Select	Answer
A	AC current and impedance
B	HF propagation
C	VHF radio propagation
D	AC voltage and impedance

15. - E4A02

Which of the following parameters would a spectrum analyzer display on the vertical and horizontal axes?

Select	Answer
A	SWR and time
B	RF amplitude and frequency
C	RF amplitude and time
D	SWR and frequency

16. - E4B05

If a frequency counter with a specified accuracy of +/- 10 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	10 Hz
B	146.52 kHz
C	1465.20 Hz
D	146.52 Hz

17. - E4C11

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

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

18. - E4D14

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

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

19. - E4E16

What current flows equally on all conductors of an unshielded multi-conductor cable?

Select	Answer
A	Reactive current only
B	Return current
C	Common-mode current
D	Differential-mode current

20. - E5A09

How is the Q of an RLC parallel resonant circuit calculated?

Select	Answer
A	Reactance of the inductance multiplied by the reactance of the capacitance
B	Resistance divided by the reactance of either the inductance or capacitance
C	Reactance of either the inductance or capacitance divided by the resistance
D	Reactance of either the inductance or capacitance multiplied by the resistance

21. - E5B05

What happens to the magnitude of a reactance when it is converted to a susceptance?

Select	Answer
A	It is shifted by 90 degrees
B	The magnitude of the susceptance is the reciprocal of the magnitude of the reactance
C	It is unchanged
D	The sign is reversed

22. - E5C04

Which of the following represents a capacitive reactance in polar coordinates?

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

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 heat in the circuit
C	It is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
D	It is dissipated as kinetic energy in the circuit

24. - E6A05

What is the alpha of a bipolar junction transistor?

Select	Answer
A	The change of base current with respect to collector current
B	The change of collector current with respect to gate current
C	The change of collector current with respect to emitter current
D	The change of collector current with respect to base current

25. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

Select	Answer
A	Much higher reverse voltage breakdown
B	Less forward voltage drop
C	Controlled reverse avalanche voltage
D	Enhanced carrier retention time

26. - E6C14

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

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

27. - E6D13

What is the primary cause of inductor self-resonance?

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

28. - E6E05

Which of the following noise figure values is typical of a low-noise UHF preamplifier?

Select	Answer
A	44 dBm
B	2 dB
C	-20 dBm
D	-10 dB

29. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

Select	Answer
A	It stays the same
B	It decreases
C	It increases
D	It becomes unstable

30. - E7A11

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

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

31. - E7B10

In Figure E7-1, what is the purpose of R1 and R2?

Select	Answer
A	Load resistors
B	Self bias
C	Feedback
D	Fixed bias

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

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

Select	Answer
A	Input voltage divided by output current
B	Input voltage multiplied by input current
C	Output voltage multiplied by output current
D	Voltage difference from input to output multiplied by output current

34. - E7E06

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

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

35. - E7F15

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters delay all frequency components of the signal by the same amount
B	FIR filters can respond faster to impulses
C	All of these choices are correct
D	FIR filters are easier to implement for a given set of passband rolloff requirements

36. - E7G03

What is the typical input impedance of an integrated circuit op-amp?

Select	Answer
A	1000 ohms
B	100 ohms
C	Very low
D	Very high

37. - E7H02

Which describes a microphonic?

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

38. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all of its harmonics?

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

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

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

40. - E8C08

How does ARQ accomplish error correction?

Select	Answer
A	Special binary codes provide automatic correction
B	If errors are detected, a retransmission is requested
C	Special polynomial codes provide automatic correction
D	If errors are detected, redundant data is substituted

41. - E8D05

What is the most common method of reducing key clicks?

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

42. - E9A08

What is meant by antenna bandwidth?

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

43. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the 3 dB beam-width?

Select	Answer
A	30 degrees
B	75 degrees
C	50 degrees
D	25 degrees

44. - E9C07

What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?

Select	Answer
A	450 ohms
B	50 ohms
C	72 ohms
D	300 ohms

45. - E9D04

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

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

46. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

Select	Answer
A	To transform the antenna impedance to a higher value
B	To cancel the inductive reactance of the matching network
C	To provide DC isolation between the feed line and the antenna
D	To provide a rejection notch that prevents the radiation of harmonics

47. - E9F10

What impedance does a 1/8 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	A capacitive reactance
B	An inductive reactance
C	The same as the characteristic impedance of the line
D	The same as the input impedance to the final generator stage

48. - E9G02

What type of coordinate system is used in a Smith chart?

Select	Answer
A	Resistance circles and reactance arcs
B	Voltage lines and current chords
C	Voltage circles and current arcs
D	Resistance lines and reactance chords

49. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	All of these choices are correct
B	Atmospheric noise is so high that gain over a dipole is not important
C	Low loss coax transmission line is essential for good performance
D	They must be erected at least 1/2 wavelength above the ground to attain good directivity

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	Polychlorinated Biphenyls
C	Polyethylene
D	Polytetrafluroethylene

Figure E7-1

Figure E9-1