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

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1. - E1A09

What is the first action you should take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

Select	Answer
A	Notify the originating station that the communication does not comply with FCC rules
B	Notify the nearest FCC Field Engineer's office
C	Discontinue forwarding the communication as soon as you become aware of it
D	Discontinue forwarding all messages

2. - E1B09

Which amateur stations may be operated under RACES rules?

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

3. - E1C01

What is a remotely controlled station?

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

4. - E1D01

What is the definition of the term telemetry?

Select	Answer
A	One-way transmission that initiates, modifies, or terminates the functions of a device at a distance
B	Two-way radiotelephone transmissions in excess of 1000 feet
C	Two-way single channel transmissions of data
D	One-way transmission of measurements at a distance from the measuring instrument

5. - E1E04

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

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

6. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

Select	Answer
A	To allow regular operation on Land Mobile channels
B	To provide additional spectrum for personal use
C	To provide temporary operation while awaiting normal licensing
D	To provide for experimental amateur communications

7. - E2A10

Why may the received signal from an amateur satellite exhibit a rapidly repeating fading effect?

Select	Answer
A	Because of the Doppler Effect
B	Because the satellite is spinning
C	Because of the satellite's low orbital altitude
D	Because of ionospheric absorption

8. - E2B15

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

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

9. - E2C07

What is the Cabrillo format?

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

10. - E2D07

What digital protocol is used by APRS?

Select	Answer
A	AX.25
B	AMTOR
C	PACTOR
D	802.11

11. - E2E04

What is indicated when one of the ellipses in an FSK crossed-ellipse display suddenly disappears?

Select	Answer
A	Selective fading has occurred
B	One of the signal filters is saturated
C	The mark and space signal have been inverted
D	The receiver has drifted 5 kHz from the desired receive frequency

12. - E3A17

What is meant by circularly polarized electromagnetic waves?

Select	Answer
A	Waves with a rotating electric field
B	Waves produced by a loop antenna
C	Waves with an electric field bent into a circular shape
D	Waves that circle the Earth

13. - E3B13

Why is chordal hop propagation desirable?

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

14. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

Select	Answer
A	Downward bending due to density variations in the atmosphere
B	Downward bending due to aurora refraction
C	D-region skip
D	E-region skip

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

Select	Answer
A	A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
B	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
C	A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude
D	A frequency standard is displayed and the probe is adjusted until the deflection time is accurate

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

Select	Answer
A	High impedance input
B	Low reluctance input
C	High reluctance input
D	Low impedance input

17. - E4C11

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

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

18. - E4D11

Why are third-order intermodulation products created within a receiver of particular interest compared to other products?

Select	Answer
A	The third-order product of two signals which are in the band of interest is also likely to be within the band
B	The third-order intercept is much higher than other orders
C	Third-order intermodulation produces three products for every input signal within the band of interest
D	Third-order products are an indication of poor image rejection

19. - E4E05

How can noise from an electric motor be suppressed?

Select	Answer
A	By installing a high pass filter in series with the motor's power leads
B	By using a ground-fault current interrupter in the circuit used to power the motor
C	By installing a bypass capacitor in series with the motor leads
D	By installing a brute-force AC-line filter in series with the motor leads

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	1.78 MHz
B	3.56 MHz
C	22.36 MHz
D	44.72 MHz

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	110 seconds
B	440 seconds
C	220 seconds
D	55 seconds

22. - E5C16

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and a 19 picofarad capacitor at 21.200 MHz?

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

23. - E5D18

How many watts are consumed in a circuit having a power factor of 0.71 if the apparent power is 500VA?

Select	Answer
A	704 W
B	252 W
C	355 W
D	1.42 mW

24. - E6A13

What do the initials CMOS stand for?

Select	Answer
A	Common Mode Organic Silicon
B	Complementary Metal-Oxide Semiconductor
C	Common Mode Oscillating System
D	Complementary Mica-Oxide Silicon

25. - E6B11

What is used to control the attenuation of RF signals by a PIN diode?

Select	Answer
A	Capacitance of an RF coupling capacitor
B	Reverse voltage larger than the RF signal
C	A sub-harmonic pump signal
D	Forward DC bias current

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

Select	Answer
A	It is totally immune to electrostatic damage
B	It has the high input impedance of CMOS and the low output impedance of bipolar transistors
C	All of these choices are correct
D	Its simplicity results in much less expensive devices than standard CMOS

27. - E6D05

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

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

28. - E6E06

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

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

29. - E6F14

Which of the following is true of LCD displays?

Select	Answer
A	They may be hard view through polarized lenses
B	They are hard to view in high ambient light conditions
C	All of these choices are correct
D	They only display alphanumeric symbols

30. - E7A12

What type of logic defines "0" as a high voltage?

Select	Answer
A	Reverse Logic
B	Positive Logic
C	Negative logic
D	Assertive Logic

31. - E7B12

What type of amplifier circuit is shown in Figure E7-1?

Select	Answer
A	Common emitter
B	Common collector
C	Common base
D	Emitter follower

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

33. - E7D10

What is the primary reason that a high-frequency switching type high voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

Select	Answer
A	The inverter design does not require any output filtering
B	The high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
C	It uses a diode bridge rectifier for increased output
D	It uses a large power factor compensation capacitor to create free power from the unused portion of the AC cycle

34. - E7E09

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

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

35. - E7F09

Why is an anti-aliasing digital filter required in a digital decimator?

Select	Answer
A	It removes high-frequency signal components which would otherwise be reproduced as lower frequency components
B	It notches out the sampling frequency to avoid sampling errors
C	It peaks the response of the decimator, improving bandwidth
D	It removes low frequency signal components to eliminate the need for DC restoration

36. - E7G12

What is an integrated circuit operational amplifier?

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

37. - E7H14

What is a phase-locked loop circuit?

Select	Answer
A	An electronic circuit also known as a monostable multivibrator
B	An electronic circuit consisting of a precision push-pull amplifier with a differential input
C	An electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
D	An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator

38. - E8A07

What determines the PEP-to-average power ratio of a single-sideband phone signal?

Select	Answer
A	The characteristics of the modulating signal
B	The amplifier gain
C	The frequency of the modulating signal
D	The degree of carrier suppression

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	3000
C	1000
D	0.3

40. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	They are the same
B	Baud is twice the symbol rate
C	Baud is only used for RTTY
D	Symbol rate is only used for packet-based modes

41. - E8D02

What spread spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?

Select	Answer
A	Binary phase-shift keying
B	Phase compandored spread spectrum
C	Direct sequence
D	Frequency hopping

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	2000 watts
B	300 watts
C	126 watts
D	317 watts

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

Select	Answer
A	Elevation
B	Radiation resistance
C	Polarization
D	Azimuth

44. - E9C05

What is an OCFD antenna?

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

45. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
B	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
C	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
D	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes

46. - E9E01

What system matches a higher impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

Select	Answer
A	The delta matching system
B	The gamma matching system
C	The stub matching system
D	The omega matching system

47. - E9F01

What is the velocity factor of a transmission line?

Select	Answer
A	The velocity of the wave in the transmission line multiplied by the velocity of light in a vacuum
B	The ratio of the characteristic impedance of the line to the terminating impedance
C	The velocity of the wave in the transmission line divided by the velocity of light in a vacuum
D	The index of shielding for coaxial cable

48. - E9G08

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

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

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

Select	Answer
A	One or more turns of wire wound in the shape of a large open coil
B	A small coil of wire tightly wound around a toroidal ferrite core
C	A large circularly polarized antenna
D	A vertical antenna coupled to a feed line through an inductive loop of wire

50. - E0A08

What does SAR measure?

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

Figure E5-2

Figure E7-1

Figure E9-2