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

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1. - E1A01

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the highest frequency at which a properly adjusted USB emission will be totally within the band?

Select	Answer
A	The exact upper band edge
B	3 kHz below the upper band edge
C	1 kHz below the upper band edge
D	300 Hz below the upper band edge

2. - E1B09

Which amateur stations may be operated under RACES rules?

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

3. - E1C07

What is meant by local control?

Select	Answer
A	Automatically manipulating local station controls
B	Controlling a station through a local auxiliary link
C	Controlling a repeater using a portable handheld transceiver
D	Direct manipulation of the transmitter by a control operator

4. - E1D05

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

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

5. - E1E04

Which of the following best describes the Volunteer Examiner accreditation process?

Select	Answer
A	The procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner
B	The amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau
C	The prospective VE obtains accreditation from the FCC
D	Each General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted

6. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

Select	Answer
A	420 MHz - 430 MHz
B	53 MHz - 54 MHz
C	440 MHz - 450 MHz
D	222 MHz - 223 MHz

7. - E2A07

Which of the following types of signals can be relayed through a linear transponder?

Select	Answer
A	SSB and SSTV
B	PSK and Packet
C	All of these choices are correct
D	FM and CW

8. - E2B11

What is the function of the Vertical Interval Signaling (VIS) code sent as part of an SSTV transmission?

Select	Answer
A	To identify the call sign of the station transmitting
B	To lock the color burst oscillator in color SSTV images
C	To identify the SSTV mode being used
D	To provide vertical synchronization

9. - E2C07

What is the Cabrillo format?

Select	Answer
A	A standard for submission of electronic contest logs
B	The rules of order for meetings between contest sponsors
C	The most common set of contest rules
D	A method of exchanging information during a contest QSO

10. - E2D08

What type of packet frame is used to transmit APRS beacon data?

Select	Answer
A	Unnumbered Information
B	Connect
C	Disconnect
D	Acknowledgement

11. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Direct FSK applies the data signal to the transmitter VFO
B	Direct FSK uses a DC-coupled data connection
C	Audio FSK can be performed anywhere in the transmit chain
D	Audio FSK has a superior frequency response

12. - E3A13

Which emission mode is best for aurora propagation?

Select	Answer
A	CW
B	RTTY
C	FM
D	SSB

13. - E3B03

What is the best time of day for transequatorial propagation?

Select	Answer
A	Morning
B	Late at night
C	Noon
D	Afternoon or early evening

14. - E3C08

What does the space weather term G5 mean?

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

15. - E4A05

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

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

16. - E4B17

What three test loads are used to calibrate a standard RF vector network analyzer?

Select	Answer
A	Short circuit, open circuit, and resonant circuit
B	Short circuit, open circuit, and 50 ohms
C	50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable
D	50 ohms, 75 ohms, and 90 ohms

17. - E4C03

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

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

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 band-pass filter in the feed line between the transmitter and receiver
D	A Class C final amplifier

19. - E4E16

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

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

20. - E5A03

What is the magnitude of the impedance of a series RLC circuit at resonance?

Select	Answer
A	High, as compared to the circuit resistance
B	Approximately equal to circuit resistance
C	Approximately equal to capacitive reactance
D	Approximately equal to inductive reactance

21. - E5B13

What letter is commonly used to represent susceptance?

Select	Answer
A	X
B	Y
C	G
D	B

22. - E5C04

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

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

23. - E5D07

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

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

24. - E6A12

Why do many MOSFET devices have internally connected Zener diodes on the gates?

Select	Answer
A	To reduce the chance of the gate insulation being punctured by static discharges or excessive voltages
B	To protect the substrate from excessive voltages
C	To provide a voltage reference for the correct amount of reverse-bias gate voltage
D	To keep the gate voltage within specifications and prevent the device from overheating

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	Controlled reverse avalanche voltage
C	Less forward voltage drop
D	Enhanced carrier retention time

26. - E6C10

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

Select	Answer
A	4
B	1
C	2
D	3

27. - E6D04

Which materials are commonly used as a slug core in a variable inductor?

Select	Answer
A	Teflon and Delrin
B	Ferrite and brass
C	Polystyrene and polyethylene
D	Cobalt and aluminum

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

29. - E6F05

Which describes an optical shaft encoder?

Select	Answer
A	A digital encryption device often used to encrypt spacecraft control signals
B	A device which detects rotation of a control by interrupting a light source with a patterned wheel
C	A device which measures the strength of a beam of light using analog to digital conversion
D	A device for generating RTTY signals by means of a rotating light source

30. - E7A04

How many flip-flops are required to divide a signal frequency by 4?

Select	Answer
A	2
B	8
C	1
D	4

31. - E7B13

In Figure E7-2, what is the purpose of R?

Select	Answer
A	Emitter load
B	Collector load
C	Fixed bias
D	Voltage regulation

32. - E7C03

What advantage does a Pi-L-network have over a regular Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

Select	Answer
A	Lower losses
B	Greater harmonic suppression
C	Higher efficiency
D	Greater transformation range

33. - E7D11

What circuit element is controlled by a series analog voltage regulator to maintain a constant output voltage?

Select	Answer
A	Error amplifier
B	Pass transistor
C	Reference voltage
D	Switching inductance

34. - E7E11

Which type of detector is used for demodulating SSB signals?

Select	Answer
A	Discriminator
B	Phase comparator
C	Product detector
D	Phase detector

35. - E7F12

What digital process is applied to I and Q signals in order to recover the baseband modulation information?

Select	Answer
A	Signal conditioning
B	Fast Fourier Transform
C	Decimation
D	Quadrature mixing

36. - E7G03

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

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

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

Select	Answer
A	Through a neutralizing capacitor
B	Through link coupling
C	Through a quartz crystal
D	Through a tapped coil

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

39. - E8B09

What is meant by deviation ratio?

Select	Answer
A	The ratio of the highest audio modulating frequency to the average audio modulating frequency
B	The ratio of the audio modulating frequency to the center carrier frequency
C	The ratio of the carrier center frequency to the audio modulating frequency
D	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency

40. - E8C05

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

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

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

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

42. - E9A06

How does the beamwidth of an antenna vary as the gain is increased?

Select	Answer
A	It increases arithmetically
B	It is essentially unaffected
C	It increases geometrically
D	It decreases

43. - E9B16

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

Select	Answer
A	1
B	7
C	3
D	4

44. - E9C15

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with its height above ground?

Select	Answer
A	The main lobe takeoff angle increases with increasing height
B	The horizontal beam width increases with height
C	The horizontal beam width decreases with height
D	The main lobe takeoff angle decreases with increasing height

45. - E9D08

What happens as the Q of an antenna increases?

Select	Answer
A	SWR bandwidth decreases
B	More common-mode current is present on the feed line
C	Gain is reduced
D	SWR bandwidth increases

46. - E9E12

What is the primary purpose of a phasing line when used with an antenna having multiple driven elements?

Select	Answer
A	It allows single-band antennas to operate on other bands
B	It prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
C	It makes sure the antenna has a low-angle radiation pattern
D	It ensures that each driven element operates in concert with the others to create the desired antenna pattern

47. - E9F16

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

Select	Answer
A	All of these choices are correct
B	Foam dielectric has lower loss per unit of length
C	Foam dielectric has lower safe operating voltage limits
D	Foam dielectric has higher velocity factor

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. - E9H05

What is the main drawback of a wire-loop antenna for direction finding?

Select	Answer
A	It is practical for use only on VHF bands
B	It receives equally well in all directions
C	It is non-rotatable
D	It has a bidirectional pattern

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

Figure E6-5

Figure E7-2

Figure E9-2