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

2. - E1B02

Which of the following factors might cause the physical location of an amateur station apparatus or antenna structure to be restricted?

Select	Answer
A	The location is of geographical or horticultural importance
B	The location is of environmental importance or significant in American history, architecture, or culture
C	The location is near an area of political conflict
D	The location is in an ITU Zone designated for coordination with one or more foreign governments

3. - E1C06

Which of the following statements concerning remotely controlled amateur stations is true?

Select	Answer
A	A control operator must be present at the control point
B	A control operator need not be present at the control point
C	Only Extra Class operators may be the control operator of a remote station
D	Repeater and auxiliary stations may not be remotely controlled

4. - E1D08

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

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

5. - E1E05

What is the minimum passing score on amateur operator license examinations?

Select	Answer
A	Minimum passing score of 74%
B	Minimum passing score of 77%
C	Minimum passing score of 70%
D	Minimum passing score of 80%

6. - E1F09

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

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

7. - E2A04

What is meant by the term mode as applied to an amateur radio satellite?

Select	Answer
A	The type of signals that can be relayed through the satellite
B	The satellite's uplink and downlink frequency bands
C	Whether the satellite is in a polar or equatorial orbit
D	The satellite's orientation with respect to the Earth

8. - E2B15

What signals SSTV receiving equipment to begin a new picture line?

Select	Answer
A	Specific tone frequencies
B	A two-tone signal
C	Specific tone amplitudes
D	Elapsed time

9. - E2C10

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

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

10. - E2D05

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

Select	Answer
A	Multi-satellite relaying
B	Store-and-forward
C	Digipeating
D	Node hopping

11. - E2E12

Which type of control is used by stations using the Automatic Link Enable (ALE) protocol?

Select	Answer
A	Automatic
B	ALE can use any type of control
C	Local
D	Remote

12. - E3A02

What characterizes libration fading of an EME signal?

Select	Answer
A	A slow change in the pitch of the CW signal
B	A fluttery irregular fading
C	A gradual loss of signal as the Sun rises
D	The returning echo is several Hertz lower in frequency than the transmitted signal

13. - E3B14

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

Select	Answer
A	Their polarization is randomly modified
B	They become elliptically polarized
C	They are bent toward the magnetic poles
D	They become phase-locked

14. - E3C11

What does VOACAP software model?

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

15. - E4A02

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

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

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S12
B	S21
C	S11
D	S22

17. - E4C11

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

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

18. - E4D08

What causes intermodulation in an electronic circuit?

Select	Answer
A	Lack of neutralization
B	Nonlinear circuits or devices
C	Too little gain
D	Positive feedback

19. - E4E09

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

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

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	218.3 kHz
B	436.6 kHz
C	15.7 kHz
D	31.4 kHz

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	110 seconds
D	440 seconds

22. - E5C17

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?

Select	Answer
A	Point 8
B	Point 1
C	Point 5
D	Point 3

23. - E5D03

What is microstrip?

Select	Answer
A	Precision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies
B	Short lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
C	Lightweight transmission line made of common zip cord
D	Miniature coax used for low power applications

24. - E6A02

Which of the following semiconductor materials contains excess free electrons?

Select	Answer
A	P-type
B	Insulated gate
C	Bipolar
D	N-type

25. - E6B09

What is a common use for point contact diodes?

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

26. - E6C06

Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?

Select	Answer
A	The input switching threshold is about one-half the power supply voltage
B	Input signals are stronger
C	The input switching threshold is about two times the power supply voltage
D	Larger bypass capacitors are used in CMOS circuit design

27. - E6D05

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

Select	Answer
A	Ferrite toroids generally have better temperature stability
B	Ferrite toroids generally require fewer turns to produce a given inductance value
C	Ferrite toroids generally have lower initial permeability
D	Ferrite toroids are easier to use with surface mount technology

28. - E6E05

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

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

29. - E6F04

What is the photovoltaic effect?

Select	Answer
A	The conversion of electrical energy to mechanical energy
B	The conversion of voltage to current when exposed to light
C	The conversion of light to electrical energy
D	The tendency of a battery to discharge when used outside

30. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It switches momentarily to the opposite binary state and then returns to its original state after a set time
B	It stores one bit of data in either a 0 or 1 state
C	It maintains a constant output voltage, regardless of variations in the input voltage
D	It produces a continuous square wave oscillating between 1 and 0

31. - E7B09

Which of the following describes how the loading and tuning capacitors are to be adjusted when tuning a vacuum tube RF power amplifier that employs a Pi-network output circuit?

Select	Answer
A	The tuning capacitor is adjusted for minimum plate current, and the loading capacitor is adjusted for maximum permissible plate current
B	The loading capacitor is set to maximum capacitance and the tuning capacitor is adjusted for minimum allowable plate current
C	The loading capacitor is adjusted to minimum plate current while alternately adjusting the tuning capacitor for maximum allowable plate current
D	The tuning capacitor is set to maximum capacitance and the loading capacitor is adjusted for minimum plate permissible current

32. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

Select	Answer
A	An active LC filter
B	A Butterworth filter
C	A passive op-amp filter
D	A Chebyshev filter

33. - E7D03

What device is typically used as a stable reference voltage in a linear voltage regulator?

Select	Answer
A	A varactor diode
B	An SCR
C	A Zener diode
D	A tunnel diode

34. - E7E07

What is meant by the term baseband in radio communications?

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

35. - E7F05

How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?

Select	Answer
A	At four times the rate of the highest frequency component of the signal
B	At half the rate of the highest frequency component of the signal
C	At twice the rate of the highest frequency component of the signal
D	At the same rate as the highest frequency component of the signal

36. - E7G12

What is an integrated circuit operational amplifier?

Select	Answer
A	A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance
B	A digital audio amplifier whose characteristics are determined by components external to the amplifier
C	A RF amplifier used in the UHF and microwave regions
D	An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit

37. - E7H10

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

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

38. - E8A13

Which of these methods is commonly used to convert analog signals to digital signals?

Select	Answer
A	Sequential sampling
B	Phase reversal
C	Level shifting
D	Harmonic regeneration

39. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

Select	Answer
A	1/3
B	2000
C	3
D	6000

40. - E8C05

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

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

41. - E8D11

What is one advantage of using ASCII code for data communications?

Select	Answer
A	It is possible to transmit both upper and lower case text
B	It includes built in error correction features
C	It contains fewer information bits per character than any other code
D	It uses one character as a shift code to send numeric and special characters

42. - E9A09

How is antenna efficiency calculated?

Select	Answer
A	(radiation resistance / total resistance) x 100 per cent
B	(effective radiated power / transmitter output) x 100 percent
C	(radiation resistance / transmission resistance) x 100 per cent
D	(total resistance / radiation resistance) x 100 per cent

43. - E9B16

How many elevation lobes appear in the forward direction of the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	4
B	3
C	7
D	1

44. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

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

45. - E9D06

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

Select	Answer
A	It is decreased
B	It is increased
C	It becomes flat
D	No change occurs

46. - E9E06

What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?

Select	Answer
A	Pi-network
B	A series capacitor
C	Pi-L-network
D	A shunt inductor

47. - E9F11

What impedance does a 1/8 wavelength transmission line present to a generator when the line is open 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 of the final generator stage

48. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning reactance values with regard to the resistance axis
B	Reassigning resistance values with regard to the reactance axis
C	Reassigning prime center with regard to the reactance axis
D	Reassigning impedance values with regard to the prime center

49. - E9H11

What characteristic of a cardioid pattern antenna is useful for direction finding?

Select	Answer
A	High-radiation angle
B	Broad band response
C	A very sharp single null
D	A very sharp peak

50. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Select	Answer
A	Each transmitter operating with a duty-cycle greater than 50 percent
B	Only commercial transmitters
C	Only the most powerful transmitter
D	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations

Figure E5-2

Figure E9-2