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

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1. - E1A08

If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

Select	Answer
A	The control operator of the originating station
B	The control operators of all the stations in the system not authenticating the source from which they accept communications
C	The control operators of all the stations in the system
D	The control operator of the packet bulletin board station

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 certified by the responsible civil defense organization for the area served
C	Any FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)
D	Any FCC-licensed amateur station except a Technician class

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. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	All of these choices are correct
B	Any amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator
C	Any amateur station designated by NASA
D	Any amateur station so designated by the ITU

5. - E1E14

For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

Select	Answer
A	Providing amateur operator license examination preparation training materials
B	Preparing, processing, administering and coordinating an examination for an amateur radio license
C	No expenses are authorized for reimbursement
D	Teaching an amateur operator license examination preparation course

6. - E1F12

Who may be the control operator of an auxiliary station?

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

7. - E2A07

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

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

8. - E2B15

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

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

9. - E2C05

What is the function of a DX QSL Manager?

Select	Answer
A	To allocate frequencies for DXpeditions
B	To relay calls to and from a DX station
C	To handle the receiving and sending of confirmation cards for a DX station
D	To run a net to allow many stations to contact a rare DX station

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

11. - E2E04

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

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

12. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

Select	Answer
A	Dust devil
B	The jet stream
C	Wind shear
D	Temperature inversion

13. - E3B05

Which amateur bands typically support long-path propagation?

Select	Answer
A	6 meters to 2 meters
B	160 meters to 10 meters
C	160 meters to 40 meters
D	30 meters to 10 meters

14. - E3C06

By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

Select	Answer
A	By approximately twice the distance
B	By approximately four times the distance
C	By approximately 50 percent of the distance
D	By approximately 15 percent of the distance

15. - E4A07

Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge to measure antenna SWR?

Select	Answer
A	Antenna analyzers do not need an external RF source
B	Antenna analyzers display a time-varying representation of the modulation envelope
C	All of these choices are correct
D	Antenna analyzers automatically tune your antenna for resonance

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	Low impedance input
D	High reluctance input

17. - E4C17

Which of the following has the largest effect on an SDR receiver's linearity?

Select	Answer
A	Anti-aliasing input filter bandwidth
B	RAM speed used for data storage
C	Analog-to-digital converter sample width in bits
D	CPU register width in bits

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	Raise the receiver IF frequency
C	Increase the receiver front end gain
D	Switch from fast AGC to slow AGC

19. - E4E07

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

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

20. - E5A12

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

Select	Answer
A	31.4 kHz
B	15.7 kHz
C	436.6 kHz
D	218.3 kHz

21. - E5B11

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?

Select	Answer
A	76 degrees with the voltage leading the current
B	14 degrees with the voltage leading the current
C	14 degrees with the voltage lagging the current
D	76 degrees with the voltage lagging the current

22. - E5C13

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

Select	Answer
A	Maidenhead grid
B	Elliptical coordinates
C	Faraday grid
D	Rectangular coordinates

23. - E5D07

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

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

24. - E6A16

What are the majority charge carriers in N-type semiconductor material?

Select	Answer
A	Free electrons
B	Free protons
C	Free neutrons
D	Holes

25. - E6B01

What is the most useful characteristic of a Zener diode?

Select	Answer
A	An internal capacitance that varies with the applied voltage
B	A negative resistance region
C	A constant voltage drop under conditions of varying current
D	A constant current drop under conditions of varying voltage

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. - E6D15

What is current in the primary winding of a transformer called if no load is attached to the secondary?

Select	Answer
A	Direct current
B	Stabilizing current
C	Magnetizing current
D	Excitation current

28. - E6E01

Which of the following is true of a charge-coupled device (CCD)?

Select	Answer
A	It samples an analog signal and passes it in stages from the input to the output
B	It is a CMOS analog-to-digital converter
C	Its phase shift changes rapidly with frequency
D	It is used in a battery charger circuit

29. - E6F06

Which of these materials is affected the most by photoconductivity?

Select	Answer
A	An ordinary metal
B	A liquid semiconductor
C	A heavy metal
D	A crystalline semiconductor

30. - E7A12

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

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

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 bias resistor equals the load resistor
C	Approximately half-way between saturation and cutoff
D	At a point where the load line intersects the zero bias current curve

32. - E7C15

What is a crystal lattice filter?

Select	Answer
A	A filter with wide bandwidth and shallow skirts made using quartz crystals
B	An audio filter made with four quartz crystals that resonate at 1kHz intervals
C	A power supply filter made with interlaced quartz crystals
D	A filter with narrow bandwidth and steep skirts made using quartz crystals

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

34. - E7E09

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

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

35. - E7F06

What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

Select	Answer
A	10 bits
B	6 bits
C	8 bits
D	4 bits

36. - E7G12

What is an integrated circuit operational amplifier?

Select	Answer
A	A digital audio amplifier whose characteristics are determined by components external to the amplifier
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	An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit

37. - E7H07

How can an oscillator's microphonic responses be reduced?

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

38. - E8A05

What would be the most accurate way of measuring the RMS voltage of a complex waveform?

Select	Answer
A	By measuring the heating effect in a known resistor
B	By using an absorption wave meter
C	By using a grid dip meter
D	By measuring the voltage with a D'Arsonval meter

39. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

Select	Answer
A	1/3
B	2000
C	6000
D	3

40. - E8C08

How does ARQ accomplish error correction?

Select	Answer
A	Special binary codes provide automatic correction
B	If errors are detected, a retransmission is requested
C	Special polynomial codes provide automatic correction
D	If errors are detected, redundant data is substituted

41. - E8D06

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

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

42. - E9A03

Why would one need to know the feed point impedance of an antenna?

Select	Answer
A	To calculate the front-to-side ratio of the antenna
B	To match impedances in order to minimize standing wave ratio on the transmission line
C	To measure the near-field radiation density from a transmitting antenna
D	To calculate the front-to-back ratio of the antenna

43. - E9B06

What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	7.5 degrees
B	75 degrees
C	45 degrees
D	25 degrees

44. - E9C10

Which of the following describes a Zepp antenna?

Select	Answer
A	A dipole constructed from zip cord
B	A vertical array capable of quickly changing the direction of maximum radiation by changing phasing lines
C	An omni-directional antenna commonly used for satellite communications
D	An end fed dipole antenna

45. - E9D02

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

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

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 series capacitor
D	A shunt inductor

47. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

Select	Answer
A	Electrical signals move more slowly in a coaxial cable than in air
B	Skin effect is less pronounced in the coaxial cable
C	The surge impedance is higher in a parallel feed line
D	The characteristic impedance is higher in a parallel feed line

48. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The resistance axis
B	The reactance axis
C	The current axis
D	The voltage axis

49. - E9H06

What is the triangulation method of direction finding?

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

50. - E0A08

What does SAR measure?

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

Figure E6-5

Figure E9-2

Figure E9-3