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. - E1B09

Which amateur stations may be operated under RACES rules?

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

3. - E1C01

What is a remotely controlled station?

Select	Answer
A	A station controlled by someone other than the licensee
B	A station operating under automatic control
C	A station controlled indirectly through a control link
D	A station operated away from its regular home location

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

Select	Answer
A	Only those of General, Advanced or Amateur Extra Class operators
B	Only those of Amateur Extra Class operators
C	Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
D	Any amateur station, subject to the privileges of the class of operator license held by the control operator

5. - E1E10

What must the administering VEs do after the administration of a successful examination for an amateur operator license?

Select	Answer
A	They must collect and send the documents to the FCC according to instructions
B	They must submit the application document to the coordinating VEC according to the coordinating VEC instructions
C	They must collect and send the documents to the NCVEC for grading
D	They must collect and submit the documents to the coordinating VEC for grading

6. - E1F07

When may an amateur station send a message to a business?

Select	Answer
A	When neither the amateur nor his or her employer has a pecuniary interest in the communications
B	When the total money involved does not exceed $25
C	When the control operator is employed by the FCC or another government agency
D	When transmitting international third-party communications

7. - E2A02

What is the direction of a descending pass for an amateur satellite?

Select	Answer
A	From north to south
B	From south to north
C	From west to east
D	From east to west

8. - E2B10

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

Select	Answer
A	10 KHz
B	15 KHz
C	20 KHz
D	3 KHz

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	All of these choices are correct
D	To separate the calling stations from the DX station

10. - E2D01

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

Select	Answer
A	Hellschreiber
B	FSK441
C	APRS
D	WSPR

11. - E2E01

Which type of modulation is common for data emissions below 30 MHz?

Select	Answer
A	Pulse modulation
B	FSK
C	Spread spectrum
D	DTMF tones modulating an FM signal

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	East
D	North

13. - E3B09

At what time of year is Sporadic E propagation most likely to occur?

Select	Answer
A	Around the equinoxes, especially the fall equinox
B	Around the solstices, especially the winter solstice
C	Around the solstices, especially the summer solstice
D	Around the equinoxes, especially the spring equinox

14. - E3C08

What does the space weather term G5 mean?

Select	Answer
A	Waning sunspot numbers
B	Moderate solar wind
C	Very low solar activity
D	An extreme geomagnetic storm

15. - E4A11

Which of the following is good practice when using an oscilloscope probe?

Select	Answer
A	All of these choices are correct
B	Never use a high impedance probe to measure a low impedance circuit
C	Never use a DC-coupled probe to measure an AC circuit
D	Keep the signal ground connection of the probe as short as possible

16. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

Select	Answer
A	Input attenuator accuracy
B	Time base accuracy
C	Temperature coefficient of the logic
D	Decade divider accuracy

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	2.4 kHz
D	1 kHz

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

19. - E4E15

Which of the following can cause shielded cables to radiate or receive interference?

Select	Answer
A	Tying all ground connections to a common point resulting in differential mode currents in the shield
B	Common mode currents on the shield and conductors
C	Low inductance ground connections at both ends of the shield
D	Use of braided shielding material

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	22.36 MHz
C	1.78 MHz
D	44.72 MHz

21. - E5B06

What is susceptance?

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

22. - E5C04

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

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

23. - E5D07

What determines the strength of the magnetic field around a conductor?

Select	Answer
A	The amount of current flowing through the conductor
B	The ratio of the current to the resistance
C	The diameter of the conductor
D	The resistance divided by the current

24. - E6A14

How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?

Select	Answer
A	An FET has high input impedance; a bipolar transistor has low input impedance
B	They are both high impedance
C	An FET has low input impedance; a bipolar transistor has high input impedance
D	They are both low impedance

25. - E6B12

What is one common use for PIN diodes?

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

26. - E6C11

In Figure E6-5, what is the schematic symbol for the NOT operation (inverter)?

Select	Answer
A	6
B	5
C	2
D	4

27. - E6D05

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

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

28. - E6E01

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

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

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

31. - E7B18

What is a characteristic of a grounded-grid amplifier?

Select	Answer
A	Low input impedance
B	High filament voltage
C	High power gain
D	Low bandwidth

32. - E7C13

What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?

Select	Answer
A	The Q of Pi-networks can be varied depending on the component values chosen
B	Pi-networks are designed for balanced input and output
C	Pi-networks have fewer components
D	L-networks cannot perform impedance transformation

33. - E7D05

Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?

Select	Answer
A	A constant current source
B	A shunt current source
C	A shunt regulator
D	A series regulator

34. - E7E09

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

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

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 the same rate as the highest frequency component of the signal
C	At twice the rate of the highest frequency component of the signal
D	At half the rate of the highest frequency component of the signal

36. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 3300 ohms and RF is 47 kilohms?

Select	Answer
A	0.07
B	28
C	14
D	7

37. - E7H03

How is positive feedback supplied in a Hartley oscillator?

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

38. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

Select	Answer
A	1 to 1
B	25 to 1
C	100 to 1
D	2.5 to 1

39. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

Select	Answer
A	3
B	0.3
C	1000
D	3000

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

Select	Answer
A	Binary Coded Decimal Code
B	Excess 3 code
C	Extended Binary Coded Decimal Interchange Code
D	Gray code

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

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

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	300 watts
B	317 watts
C	126 watts
D	2000 watts

43. - E9B14

What type of information can be obtained by submitting the details of a proposed new antenna to a modeling program?

Select	Answer
A	SWR vs frequency charts
B	All of these choices are correct
C	Polar plots of the far field elevation and azimuth patterns
D	Antenna gain

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 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. - 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	Improved radiation efficiency
D	Lower Q

46. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

Select	Answer
A	The gamma match
B	The stub match
C	The epsilon match
D	The delta match

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	The same as the characteristic impedance of the line
C	The same as the input impedance to the final generator stage
D	An inductive reactance

48. - E9G10

What do the arcs on a Smith chart represent?

Select	Answer
A	Frequency
B	SWR
C	Points with constant resistance
D	Points with constant reactance

49. - E9H08

What is the function of a sense antenna?

Select	Answer
A	It allows DF antennas to receive signals at different vertical angles
B	It modifies the pattern of a DF antenna array to provide a null in one direction
C	It increases the sensitivity of a DF antenna array
D	It provides diversity reception that cancels multipath signals

50. - E0A08

What does SAR measure?

Select	Answer
A	Signal Amplification Rating
B	Synthetic Aperture Ratio of the human body
C	The rate of RF energy reflected from stationary terrain
D	The rate at which RF energy is absorbed by the body

Figure E6-5

Figure E7-4