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

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1. - E1A13

Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?

Select	Answer
A	Only a person with an FCC Marine Radio
B	Any person named in an amateur station license grant or a person holding an unrestricted Radiotelephone Operator Permit
C	Any person holding an FCC issued amateur license or who is authorized for alien reciprocal operation
D	Only a person named in an amateur station license grant

2. - E1B05

What is the National Radio Quiet Zone?

Select	Answer
A	An area in Florida surrounding Cape Canaveral
B	An area surrounding the National Radio Astronomy Observatory
C	An area in New Mexico surrounding the White Sands Test Area
D	An area in Puerto Rico surrounding the Arecibo Radio Telescope

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	Communications incidental to the purpose of the amateur service and remarks of a personal nature
B	Business-related messages for non-profit organizations
C	Messages intended for connection to users of the maritime satellite service
D	All of these choices are correct

4. - E1D03

What is a telecommand station in the amateur satellite service?

Select	Answer
A	An amateur station that transmits communications to initiate, modify or terminate functions of a space station
B	An amateur station located more than 50 km above the Earth's surface
C	An amateur station that transmits telemetry consisting of measurements of upper atmosphere
D	An amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites

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

6. - E1F07

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

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

7. - E2A07

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

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

8. - E2B04

What is blanking in a video signal?

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

9. - E2C01

Which of the following is true about contest operating?

Select	Answer
A	Interference to other amateurs is unavoidable and therefore acceptable
B	Operators are permitted to make contacts even if they do not submit a log
C	It is mandatory to transmit the call sign of the station being worked as part of every transmission to that station
D	Every contest requires a signal report in the exchange

10. - E2D02

Which of the following is a good technique for making meteor scatter contacts?

Select	Answer
A	Short transmission with rapidly repeated call signs and signal reports
B	Use of high speed CW or digital modes
C	All of these choices are correct
D	15 second timed transmission sequences with stations alternating based on location

11. - E2E04

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

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

12. - E3A07

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

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

13. - E3B09

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

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

14. - E3C10

What does the 304A solar parameter measure?

Select	Answer
A	The solar emission at 304 GHz, correlated to X-Ray flare levels
B	The ratio of X-Ray flux to radio flux, correlated to sunspot number
C	The solar wind velocity at 304 degrees from the solar equator, correlated to solar activity
D	UV emissions at 304 angstroms, correlated to solar flux index

15. - E4A03

Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?

Select	Answer
A	A time-domain reflectometer
B	A spectrum analyzer
C	A logic analyzer
D	A wattmeter

16. - E4B02

What is an advantage of using a bridge circuit to measure impedance?

Select	Answer
A	It is relatively immune to drift in the signal generator source
B	It provides an excellent match under all conditions
C	It is very precise in obtaining a signal null
D	It can display results directly in Smith chart format

17. - E4C15

What is usually the primary source of noise that is heard from an HF receiver with an antenna connected?

Select	Answer
A	Receiver front-end noise
B	Induction motor noise
C	Atmospheric noise
D	Detector noise

18. - E4D10

What does a third-order intercept level of 40 dBm mean with respect to receiver performance?

Select	Answer
A	The receiver can tolerate signals up to 40 dB above the noise floor without producing third-order intermodulation products
B	Signals less than 40 dBm will not generate audible third-order intermodulation products
C	A pair of 40 dBm signals will theoretically generate a third-order intermodulation product with the same level as the input signals
D	A pair of 1 mW input signals will produce a third-order intermodulation product which is 40 dB stronger than the input signal

19. - E4E07

How can you determine if line noise interference is being generated within your home?

Select	Answer
A	By observing the AC power line voltage with a spectrum analyzer
B	By turning off the AC power line main circuit breaker and listening on a battery operated radio
C	By observing the AC power line waveform with an oscilloscope
D	By checking the power line voltage with a time domain reflectometer

20. - E5A05

What is the magnitude of the current at the input of a series RLC circuit as the frequency goes through resonance?

Select	Answer
A	L/R
B	Maximum
C	Minimum
D	R/L

21. - E5B10

What is the relationship between the current through an inductor and the voltage across an inductor?

Select	Answer
A	Voltage and current are 180 degrees out of phase
B	Voltage and current are in phase
C	Current leads voltage by 90 degrees
D	Voltage leads current by 90 degrees

22. - E5C17

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?

Select	Answer
A	Point 5
B	Point 1
C	Point 8
D	Point 3

23. - E5D16

What is the power factor of an R-L circuit having a 30 degree phase angle between the voltage and the current?

Select	Answer
A	0.577
B	0.5
C	1.73
D	0.866

24. - E6A05

What is the alpha of a bipolar junction transistor?

Select	Answer
A	The change of base current with respect to collector current
B	The change of collector current with respect to emitter current
C	The change of collector current with respect to base current
D	The change of collector current with respect to gate current

25. - E6B08

Which of the following describes a type of semiconductor diode?

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

26. - E6C03

What is tri-state logic?

Select	Answer
A	Proprietary logic devices manufactured by Tri-State Devices
B	Logic devices that utilize ternary math
C	Logic devices with 0, 1, and high impedance output states
D	Low power logic devices designed to operate at 3 volts

27. - E6D14

Which type of slug material decreases inductance when inserted into a coil?

Select	Answer
A	Brass
B	Ceramic
C	Powdered-iron
D	Ferrite

28. - E6E12

Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?

Select	Answer
A	High-voltage insulating ability
B	To provide a low-pass frequency response
C	Better dissipation of heat
D	Enhanced sensitivity to light

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

30. - E7A11

What type of logic defines "1" as a high voltage?

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

31. - E7B10

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

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

32. - E7C09

What is a Jones filter as used as part of an HF receiver IF stage?

Select	Answer
A	A variable bandwidth crystal lattice filter
B	A filter that removes impulse noise E7C10 (B) Which of the following filters would be the best choice for use in a 2 meter repeater duplexer? A. A crystal filter B. A cavity filter C. A DSP filter D. An L-C filter
C	An automatic notch filter
D	A special filter that emphasizes image responses

33. - E7D14

What is one purpose of a "bleeder" resistor in a conventional unregulated power supply?

Select	Answer
A	To improve output voltage regulation
B	To balance the low-voltage filament windings
C	To cut down on waste heat generated by the power supply
D	To boost the amount of output current

34. - E7E03

How does an analog phase modulator function?

Select	Answer
A	By varying the tuning of a microphone preamplifier to produce PM signals
B	By varying the tuning of an amplifier tank circuit to produce PM signals
C	By varying the tuning of a microphone preamplifier to produce AM signals
D	By varying the tuning of an amplifier tank circuit to produce AM signals

35. - E7F11

What sets the minimum detectable signal level for an SDR in the absence of atmospheric or thermal noise?

Select	Answer
A	Data storage transfer rate
B	Sample clock phase noise
C	Missing codes and jitter
D	Reference voltage level and sample width in bits

36. - E7G02

What is the effect of ringing in a filter?

Select	Answer
A	An echo caused by a long time delay
B	A reduction in high frequency response
C	Undesired oscillations added to the desired signal
D	Partial cancellation of the signal over a range of frequencies

37. - E7H07

How can an oscillator's microphonic responses be reduced?

Select	Answer
A	Mechanically isolating the oscillator circuitry from its enclosure
B	Using the oscillator only for CW and digital signals
C	Eliminating noise on the oscillator's power supply
D	Use of NP0 capacitors

38. - E8A12

What is an advantage of using digital signals instead of analog signals to convey the same information?

Select	Answer
A	Less complex circuitry is required for digital signal generation and detection
B	Digital signals can be regenerated multiple times without error
C	All of these choices are correct
D	Digital signals always occupy a narrower bandwidth

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. - E8C06

What is the necessary bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

Select	Answer
A	0.3 kHz
B	0.1 Hz
C	1.0 kHz
D	0.5 kHz

41. - E8D12

What is the advantage of including a parity bit with an ASCII character stream?

Select	Answer
A	The signal can overpower interfering signals
B	Foreign language characters can be sent
C	Some types of errors can be detected SUBELEMENT E9 - ANTENNAS AND TRANSMISSION LINES [8 Exam Questions - 8 Groups] E9A Basic Antenna parameters: radiation resistance, gain, beamwidth, efficiency, beamwidth; effective radiated power, polarization E9A01 (C) What describes an isotropic antenna? A. A grounded antenna used to measure earth conductivity B. A horizontally polarized antenna used to compare Yagi antennas C. A theoretical antenna used as a reference for antenna gain D. A spacecraft antenna used to direct signals toward the earth
D	Faster transmission rate

42. - E9A14

What is meant by the radiation resistance of an antenna?

Select	Answer
A	The combined losses of the antenna elements and feed line
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 resistance in the atmosphere that an antenna must overcome to be able to radiate a signal

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

Select	Answer
A	15 dB
B	28 dB
C	24 dB
D	3 dB

44. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?

Select	Answer
A	The high-angle radiation increases
B	Both the high-angle and low-angle radiation decrease
C	The low-angle radiation increases
D	The low-angle radiation decreases

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Higher losses
B	Lower Q
C	Greater structural strength
D	Improved radiation efficiency

46. - E9E10

Which of these choices is an effective way to match an antenna with a 100 ohm feed point impedance to a 50 ohm coaxial cable feed line?

Select	Answer
A	Connect a 1/4-wavelength open stub of 300 ohm twin-lead in parallel with the coaxial feed line where it connects to the antenna
B	Connect 1/2 wavelength shorted stub of 75 ohm cable in parallel with the 50 ohm cable where it attaches to the antenna
C	Insert a 1/2 wavelength piece of 300 ohm twin-lead in series between the antenna terminals and the 50 ohm feed cable
D	Insert a 1/4-wavelength piece of 75 ohm coaxial cable transmission line in series between the antenna terminals and the 50 ohm feed cable

47. - E9F08

What is the term for the ratio of the actual speed at which a signal travels through a transmission line to the speed of light in a vacuum?

Select	Answer
A	Velocity factor
B	Standing wave ratio
C	Characteristic impedance
D	Surge impedance

48. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

Select	Answer
A	Antenna-length circles
B	Coaxial-length circles
C	Standing wave ratio circles
D	Radiation-pattern circles

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 has a bidirectional pattern
D	It is non-rotatable

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Zinc oxide
B	Mica
C	Beryllium Oxide
D	Uranium Hexafluoride

Figure E5-2

Figure E7-1

Figure E9-2