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

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1. - E1A07

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

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

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	10 miles
B	30 miles
C	3 miles
D	1 mile

3. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

Select	Answer
A	ITU reciprocal license
B	IARP agreement
C	All of these choices are correct
D	CEPT agreement

4. - E1D05

What class of licensee is authorized to be the control operator of a space station?

Select	Answer
A	Any class with appropriate operator privileges
B	Only Amateur Extra Class
C	All except Technician Class
D	Only General, Advanced or Amateur Extra Class

5. - E1E03

What is a Volunteer Examiner Coordinator?

Select	Answer
A	A person who has volunteered to prepare amateur operator license examinations
B	An organization that has entered into an agreement with the FCC to coordinate amateur operator license examinations
C	A person who has volunteered to administer amateur operator license examinations
D	The person who has entered into an agreement with the FCC to be the VE session manager

6. - E1F12

Who may be the control operator of an auxiliary station?

Select	Answer
A	Only Amateur Extra Class operators
B	Any licensed amateur operator
C	Only General, Advanced or Amateur Extra Class operators
D	Only Technician, General, Advanced or Amateur Extra Class operators

7. - E2A08

Why should effective radiated power to a satellite which uses a linear transponder be limited?

Select	Answer
A	To prevent the satellite from emitting out-of-band signals
B	To avoid interfering with terrestrial QSOs
C	To avoid reducing the downlink power to all other users
D	To prevent creating errors in the satellite telemetry

8. - E2B15

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

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

9. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

Select	Answer
A	Send only the last two letters of your call sign until you make contact
B	Send your full call sign and grid square
C	Send your full call sign once or twice
D	Send the call sign of the DX station three times, the words "this is", then your call sign three times

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

11. - E2E12

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

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

12. - E3A07

Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?

Select	Answer
A	Forests
B	Urban areas
C	Bodies of water
D	Mountain ranges

13. - E3B10

What is the cause of gray-line propagation?

Select	Answer
A	In darkness, solar absorption drops greatly while atmospheric ionization remains steady
B	At mid-afternoon, the Sun heats the ionosphere decreasing radio wave refraction and the MUF
C	At twilight and sunrise, D-layer absorption is low while E-layer and F-layer propagation remains high
D	At midday, the Sun super heats the ionosphere causing increased refraction of radio waves

14. - E3C11

What does VOACAP software model?

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

15. - E4A05

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

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

16. - E4B14

What happens if a dip meter is too tightly coupled to a tuned circuit being checked?

Select	Answer
A	Intermodulation distortion occurs
B	Harmonics are generated
C	A less accurate reading results
D	Cross modulation occurs

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

Select	Answer
A	Desensitization
B	Capture effect
C	Cross-modulation interference
D	Frequency discrimination

18. - E4D14

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

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

19. - E4E14

What is one type of electrical interference that might be caused by the operation of a nearby personal computer?

Select	Answer
A	A whining type noise that continually pulses off and on
B	A loud AC hum in the audio output of your station receiver
C	The appearance of unstable modulated or unmodulated signals at specific frequencies
D	A clicking noise at intervals of a few seconds

20. - E5A09

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

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

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

22. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

Select	Answer
A	Far field diagram
B	Near field diagram
C	Venn diagram
D	Phasor diagram

23. - E5D11

What is the power factor of an R-L circuit having a 60 degree phase angle between the voltage and the current?

Select	Answer
A	1.414
B	0.866
C	1.73
D	0.5

24. - E6A07

Which of the following indicates that a silicon NPN junction transistor is biased on?

Select	Answer
A	Base-to-emitter voltage of approximately 0.6 to 0.7 volts
B	Base-to-emitter resistance of approximately 0.6 to 0.7 ohms
C	Base-to-emitter voltage of approximately 6 to 7 volts
D	Base-to-emitter resistance of approximately 6 to 7 ohms

25. - E6B08

Which of the following describes a type of semiconductor diode?

Select	Answer
A	CMOS-field effect
B	Metal-semiconductor junction
C	Thermionic emission diode
D	Electrolytic rectifier

26. - E6C07

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

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

27. - E6D12

What is the definition of saturation in a ferrite core inductor?

Select	Answer
A	The ability of the inductor's core to store magnetic energy has been exceeded
B	Adjacent inductors become over-coupled
C	The inductor's voltage rating is exceeded causing a flashover
D	The inductor windings are over coupled

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 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	It is a CMOS analog-to-digital converter

29. - E6F04

What is the photovoltaic effect?

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

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	J-K flip-flop
D	Astable multivibrator

31. - E7B10

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

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

32. - E7C04

How does an impedance-matching circuit transform a complex impedance to a resistive impedance?

Select	Answer
A	It cancels the reactive part of the impedance and changes the resistive part to a desired value
B	Network resistances are substituted for load resistances and reactances are matched to the resistances
C	It introduces transconductance to cancel the reactive part of impedance
D	It introduces negative resistance to cancel the resistive part of impedance

33. - E7D09

What is the main reason to use a charge controller with a solar power system?

Select	Answer
A	Prevention of battery undercharge
B	Control of electrolyte levels during battery discharge
C	Prevention of battery damage due to overcharge
D	Matching of day and night charge rates

34. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

Select	Answer
A	The sum, difference and square root of the input frequencies
B	Two and four times the original frequency
C	1.414 and 0.707 times the input frequency
D	The two input frequencies along with their sum and difference frequencies

35. - E7F08

What is the function of decimation with regard to digital filters?

Select	Answer
A	Converting data to binary code decimal form
B	Attenuating the signal
C	Removing unnecessary significant digits
D	Reducing the effective sample rate by removing samples

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. - E7H11

What are the major spectral impurity components of direct digital synthesizers?

Select	Answer
A	Spurious signals at discrete frequencies
B	Nyquist limit noise
C	Broadband noise
D	Digital conversion noise

38. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

Select	Answer
A	Very low power consumption decreases frequency drift
B	Immunity to out of sequence coding reduces spurious responses
C	All of these choices are correct
D	Very high speed allows digitizing high frequencies

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	The transmitted signal jumps from band to band at a predetermined rate
B	The transmitted signal is divided into packets of information
C	Two or more information streams are merged into a baseband, which then modulates the transmitter
D	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter

40. - E8C07

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

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

41. - E8D08

What parameter might indicate that excessively high input levels are causing distortion in an AFSK signal?

Select	Answer
A	Repeat Request Rate (RRR)
B	Baud rate
C	Signal to noise ratio
D	Intermodulation Distortion (IMD)

42. - E9A10

Which of the following choices is a way to improve the efficiency of a ground-mounted quarter-wave vertical antenna?

Select	Answer
A	Reduce the diameter of the radiating element
B	Install a good radial system
C	Isolate the coax shield from ground
D	Shorten the radiating element

43. - E9B01

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

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

44. - E9C12

Which of the following describes an extended double Zepp antenna?

Select	Answer
A	A center fed 1.25 wavelength antenna (two 5/8 wave elements in phase)
B	An end fed folded dipole antenna
C	A portable antenna erected using two push support poles
D	A wideband vertical antenna constructed from precisely tapered aluminum tubing

45. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

Select	Answer
A	To lower the losses
B	To increase the SWR bandwidth
C	To cancel capacitive reactance
D	To lower the Q

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	Pi-L-network
C	A shunt inductor
D	A series capacitor

47. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically one-half wavelength long at 14.10 MHz?

Select	Answer
A	20 meters
B	10 meters
C	15 meters
D	71 meters

48. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

Select	Answer
A	Voltage and impedance
B	Resistance and voltage
C	Reactance and voltage
D	Resistance and reactance

49. - E9H06

What is the triangulation method of direction finding?

Select	Answer
A	A fixed receiving station plots three headings to the signal source
B	Antenna headings from several different receiving locations are used to locate the signal source
C	A fixed receiving station uses three different antennas to plot the location of the signal source
D	The geometric angles of sky waves from the source are used to determine its position

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 the most powerful transmitter
C	Only commercial transmitters
D	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations

Figure E7-1

Figure E7-4

Figure E9-1