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

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1. - E1A12

With your transceiver displaying the carrier frequency of CW signals, you hear a DX station's CQ on 3.500 MHz. Is it legal to return the call using CW on the same frequency?

Select	Answer
A	No, one of the sidebands of the CW signal will be out of the band
B	Yes, the DX station initiated the contact
C	Yes, the displayed frequency is within the 80 meter CW band segment
D	No, U.S. stations are not permitted to use CW emissions below 3.525 MHz

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	An Environmental Assessment must be submitted to the FCC
C	A proposal must be submitted to the National Park Service
D	A letter of intent must be filed with the National Audubon Society

3. - E1C04

What is meant by IARP?

Select	Answer
A	The internal amateur radio practices policy of the FCC
B	A forecast of intermittent aurora radio propagation
C	An indication of increased antenna reflected power
D	An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas

4. - E1D02

What is the amateur satellite service?

Select	Answer
A	A spacecraft launching service for amateur-built satellites
B	A radio communications service using stations on Earth satellites for public service broadcast
C	A radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
D	A radio communications service using amateur radio stations on satellites

5. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

Select	Answer
A	Return the application document to the examinee
B	Maintain the application form with the VEC's records
C	Destroy the application form
D	Send the application form to the FCC and inform the FCC of the grade

6. - E1F12

Who may be the control operator of an auxiliary station?

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

7. - E2A13

What type of satellite appears to stay in one position in the sky?

Select	Answer
A	Geomagnetic
B	Geostationary
C	LEO
D	HEO

8. - E2B04

What is blanking in a video signal?

Select	Answer
A	Synchronization of the horizontal and vertical sync pulses
B	Turning off the scanning beam at the conclusion of a transmission
C	Turning off the scanning beam while it is traveling from right to left or from bottom to top
D	Transmitting a black and white test pattern

9. - E2C12

What might help to restore contact when DX signals become too weak to copy across an entire HF band a few hours after sunset?

Select	Answer
A	Wait 90 minutes or so for the signal degradation to pass
B	Switch to a higher frequency HF band
C	Wait 24 hours before attempting another communication on the band
D	Switch to a lower frequency HF band

10. - E2D04

What is the purpose of digital store-and-forward functions on an Amateur Radio satellite?

Select	Answer
A	To delay download of telemetry between satellites
B	To store digital messages in the satellite for later download by other stations
C	To relay messages between satellites
D	To upload operational software for the transponder

11. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

Select	Answer
A	PSK31
B	RTTY
C	PACTOR
D	MT63

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	East
B	West
C	North
D	South

13. - E3B13

Why is chordal hop propagation desirable?

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

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	Southward
B	Northward
C	Westward
D	Eastward

15. - E4A06

What is the effect of aliasing in a digital or computer-based oscilloscope?

Select	Answer
A	Calibration of the vertical scale is no longer valid
B	All signals will have a DC offset
C	False triggering occurs
D	False signals are displayed

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	146.52 kHz
B	1465.20 Hz
C	146.52 Hz
D	10 Hz

17. - E4C09

Which of the following choices is a good reason for selecting a high frequency for the design of the IF in a conventional HF or VHF communications receiver?

Select	Answer
A	Improved receiver noise figure
B	Easier for front-end circuitry to eliminate image responses
C	Fewer components in the receiver
D	Reduced drift

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

19. - E4E08

What type of signal is picked up by electrical wiring near a radio antenna?

Select	Answer
A	An electrical-sparking signal
B	Harmonics of the AC power line frequency
C	A common-mode signal at the frequency of the radio transmitter
D	A differential-mode signal at the AC power line frequency

20. - E5A13

What is an effect of increasing Q in a resonant circuit?

Select	Answer
A	Phase shift can become uncontrolled
B	Parasitic effects are minimized
C	Fewer components are needed for the same performance
D	Internal voltages and circulating currents increase

21. - E5B01

What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the applied voltage?

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

22. - E5C15

Which point in Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and an 18 microhenry inductor at 3.505 MHz?

Select	Answer
A	Point 1
B	Point 8
C	Point 7
D	Point 3

23. - E5D04

Why are short connections necessary at microwave frequencies?

Select	Answer
A	To reduce phase shift along the connection
B	To increase neutralizing resistance
C	Because of ground reflections
D	To reduce noise figure

24. - E6A10

In Figure E6-2, what is the schematic symbol for an N-channel dual-gate MOSFET?

Select	Answer
A	6
B	2
C	4
D	5

25. - E6B08

Which of the following describes a type of semiconductor diode?

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

26. - E6C10

In Figure E6-5, what is the schematic symbol for a NOR gate?

Select	Answer
A	3
B	4
C	2
D	1

27. - E6D12

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

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

28. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

Select	Answer
A	Nearly infinite gain, very high input impedance, and very low output impedance
B	Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range
C	The ability to retrieve information from a single signal even in the presence of other strong signals
D	Plate current that is controlled by a control grid

29. - E6F13

What is a liquid crystal display (LCD)?

Select	Answer
A	A modern replacement for a quartz crystal oscillator which displays its fundamental frequency
B	A display that uses a glowing liquid to remain brightly lit in dim light
C	A frequency-determining unit for a transmitter or receiver
D	A display utilizing a crystalline liquid and polarizing filters which becomes opaque when voltage is applied

30. - E7A08

What logical operation does an OR gate perform?

Select	Answer
A	It produces logic "1" at its output if any or all inputs are logic "1"
B	It only produces logic "0" at its output when all inputs are logic "1"
C	It produces logic "0" at its output if all inputs are logic "1"
D	It produces logic "1" at its output if all inputs are logic "0"

31. - E7B04

Where on the load line of a Class A common emitter amplifier would bias normally be set?

Select	Answer
A	Where the load line intersects the voltage axis
B	At a point where the load line intersects the zero bias current curve
C	At a point where the bias resistor equals the load resistor
D	Approximately half-way between saturation and cutoff

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

33. - E7D09

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

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

34. - E7E09

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

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

35. - E7F16

How might the sampling rate of an existing digital signal be adjusted by a factor of 3/4?

Select	Answer
A	Add 3 to each input value and subtract 4 from each output value
B	Interpolate by a factor of three, then decimate by a factor of four
C	Multiply each sample value by a factor of 3/4
D	Change the gain by a factor of 3/4

36. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

Select	Answer
A	It decreases logarithmically with increasing frequency
B	It increases linearly with increasing frequency
C	It decreases linearly with increasing frequency
D	It does not vary with frequency

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

Select	Answer
A	Wirewound resistors
B	NP0 capacitors
C	Non-inductive resistors
D	Toroidal inductors

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	Very high speed allows digitizing high frequencies
C	Immunity to out of sequence coding reduces spurious responses
D	All of these choices are correct

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. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By the receiving station repeating each block of three data characters
B	By transmitting a special algorithm to the receiving station along with the data characters
C	By varying the frequency shift of the transmitted signal according to a predefined algorithm
D	By transmitting extra data that may be used to detect and correct transmission errors

41. - E8D06

Which of the following indicates likely overmodulation of an AFSK signal such as PSK or MFSK?

Select	Answer
A	High reflected power
B	Harmonics on higher bands
C	Strong ALC action
D	Rapid signal fading

42. - E9A14

What is meant by the radiation resistance of an antenna?

Select	Answer
A	The resistance in the atmosphere that an antenna must overcome to be able to radiate a signal
B	The value of a resistance that would dissipate the same amount of power as that radiated from an antenna
C	The specific impedance of the antenna
D	The combined losses of the antenna elements and feed line

43. - E9B12

What is the far field of an antenna?

Select	Answer
A	The region where the shape of the antenna pattern is independent of distance
B	The region where radiated power dissipates over a specified time period
C	The region of the ionosphere where radiated power is not refracted
D	The region where radiated field strengths are obstructed by objects of reflection

44. - E9C05

What is an OCFD antenna?

Select	Answer
A	A multiband dipole antenna using one-way circular polarization for frequency diversity
B	A remotely tunable dipole antenna using orthogonally controlled frequency diversity
C	An eight band dipole antenna using octophase filters
D	A dipole feed approximately 1/3 the way from one end with a 4:1 balun to provide multiband operation

45. - E9D12

Which of the following would provide the best RF ground for your station?

Select	Answer
A	An electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
B	An electrically short connection to a metal water pipe
C	An electrically short connection to 3 or 4 interconnected ground rods via a series RF choke
D	A 50 ohm resistor connected to ground

46. - E9E07

What term best describes the interactions at the load end of a mismatched transmission line?

Select	Answer
A	Characteristic impedance
B	Dielectric constant
C	Reflection coefficient
D	Velocity factor

47. - E9F15

What impedance does a 1/2 wavelength transmission line present to a generator when the line is open at the far end?

Select	Answer
A	The same as the characteristic impedance of the line
B	Very high impedance
C	Very low impedance
D	The same as the output impedance of the generator

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. - E9H10

How can the output voltage of a multiple turn receiving loop antenna be increased?

Select	Answer
A	By winding adjacent turns in opposing directions
B	By increasing either the number of wire turns in the loop or the area of the loop structure or both
C	By reducing the permeability of the loop shield
D	By increasing the number of wire turns in the loop and reducing the area of the loop structure

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	The high gain antennas commonly used can result in high exposure levels
C	Microwaves are ionizing radiation
D	Microwaves often travel long distances by ionospheric reflection

Figure E5-2

Figure E6-2

Figure E6-5