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

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1. - E1A11

Which of the following describes authorization or licensing required when operating an amateur station aboard a U.S.-registered vessel in international waters?

Select	Answer
A	Any FCC-issued amateur license
B	Any amateur license with an FCC Marine or Aircraft endorsement
C	An unrestricted Radiotelephone Operator Permit
D	Only General class or higher amateur licenses

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	3 miles
B	10 miles
C	30 miles
D	1 mile

3. - E1C05

When may an automatically controlled station originate third party communications?

Select	Answer
A	Only when transmitting RTTY or data emissions
B	When approved by the National Telecommunication and Information Administration
C	Never
D	When agreed upon by the sending or receiving station

4. - E1D06

Which of the following is a requirement of a space station?

Select	Answer
A	All of these choices are correct
B	The space station must be capable of terminating transmissions by telecommand when directed by the FCC
C	The space station must cease all transmissions after 5 years
D	The space station must be capable of changing its orbit whenever such a change is ordered by NASA

5. - E1E08

To which of the following examinees may a VE not administer an examination?

Select	Answer
A	Employees of the VE
B	Relatives of the VE as listed in the FCC rules
C	All of these choices are correct
D	Friends of the VE

6. - E1F11

Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

Select	Answer
A	It must produce full legal output when driven by not more than 5 watts of mean RF input power
B	It must be capable of external RF switching between its input and output networks
C	It must exhibit a gain of 0 dB or less over its full output range
D	It must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power

7. - E2A08

Why should effective radiated power to a satellite which uses a linear transponder be limited?

Select	Answer
A	To prevent creating errors in the satellite telemetry
B	To avoid interfering with terrestrial QSOs
C	To avoid reducing the downlink power to all other users
D	To prevent the satellite from emitting out-of-band signals

8. - E2B06

What is vestigial sideband modulation?

Select	Answer
A	A type of modulation in which one sideband is inverted
B	Spread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation
C	Amplitude modulation in which one complete sideband and a portion of the other are transmitted
D	Narrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier

9. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

Select	Answer
A	Repeater contacts between U.S. club members
B	Contacts using tactical call signs
C	Special event contacts between stations in the U.S.
D	Contacts between a U.S. station and a non-U.S. station

10. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
B	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
C	All of these choices are correct
D	An APRS station with a GPS unit can automatically transmit information to show a mobile station's position during the event

11. - E2E06

What is the most common data rate used for HF packet?

Select	Answer
A	1200 baud
B	300 baud
C	48 baud
D	110 baud

12. - E3A10

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

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

13. - E3B14

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

Select	Answer
A	Their polarization is randomly modified
B	They become phase-locked
C	They become elliptically polarized
D	They are bent toward the magnetic poles

14. - E3C15

What might a sudden rise in radio background noise indicate?

Select	Answer
A	Long-path propagation is occurring
B	Increased transequatorial propagation likely
C	A meteor ping
D	A solar flare has occurred

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

16. - E4B04

If a frequency counter with a specified accuracy of +/- 0.1 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	1.4652 Hz
B	0.1 MHz
C	1.4652 kHz
D	14.652 Hz

17. - E4C15

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

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

18. - E4D14

Which of the following is a way to reduce the likelihood of receiver desensitization?

Select	Answer
A	Increase the receiver front end gain
B	Raise the receiver IF frequency
C	Decrease the RF bandwidth of the receiver
D	Switch from fast AGC to slow AGC

19. - E4E11

Which is the most likely cause if you are hearing combinations of local AM broadcast signals within one or more of the MF or HF ham bands?

Select	Answer
A	Nearby corroded metal joints are mixing and re-radiating the broadcast signals
B	Your station receiver IF amplifier stage is defective
C	The broadcast station is transmitting an over-modulated signal
D	You are receiving sky wave signals from a distant station

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	22.36 MHz
B	3.56 MHz
C	1.78 MHz
D	44.72 MHz

21. - E5B07

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

Select	Answer
A	14.0 degrees with the voltage lagging the current
B	68.2 degrees with the voltage leading the current
C	14.0 degrees with the voltage leading the current
D	68.2 degrees with the voltage lagging the current

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 3
B	Point 1
C	Point 8
D	Point 7

23. - E5D17

How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200VAC at 5 amperes?

Select	Answer
A	200 watts
B	1600 watts
C	1000 watts
D	600 watts

24. - E6A02

Which of the following semiconductor materials contains excess free electrons?

Select	Answer
A	P-type
B	Bipolar
C	N-type
D	Insulated gate

25. - E6B13

What type of bias is required for an LED to emit light?

Select	Answer
A	Reverse bias
B	Forward bias
C	Zero bias
D	Inductive bias

26. - E6C03

What is tri-state logic?

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

27. - E6D06

What core material property determines the inductance of a toroidal inductor?

Select	Answer
A	Thermal impedance
B	Reactivity
C	Permeability
D	Resistance

28. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	PLCC
B	Ball grid array
C	SOT
D	DIP

29. - E6F03

What is the most common configuration of an optoisolator or optocoupler?

Select	Answer
A	A frequency modulated helium-neon laser
B	A lens and a photomultiplier
C	An amplitude modulated helium-neon laser
D	An LED and a phototransistor

30. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

Select	Answer
A	A multiplexer
B	An OR gate
C	An XOR gate
D	A flip-flop

31. - E7B17

Why are odd-order rather than even-order intermodulation distortion products of concern in linear power amplifiers?

Select	Answer
A	Because they maintain the sidebands, thus causing multiple duplicate signals
B	Because they are relatively far in frequency from the desired signal
C	Because they are relatively close in frequency to the desired signal
D	Because they invert the sidebands causing distortion

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

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

Select	Answer
A	Input voltage multiplied by input current
B	Voltage difference from input to output multiplied by output current
C	Input voltage divided by output current
D	Output voltage multiplied by output current

34. - E7E01

Which of the following can be used to generate FM phone emissions?

Select	Answer
A	A balanced modulator on the oscillator
B	A reactance modulator on the oscillator
C	A balanced modulator on the audio amplifier
D	A reactance modulator on the final amplifier

35. - E7F15

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters delay all frequency components of the signal by the same amount
B	FIR filters are easier to implement for a given set of passband rolloff requirements
C	All of these choices are correct
D	FIR filters can respond faster to impulses

36. - E7G08

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

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

37. - E7H10

What information is contained in the lookup table of a direct digital frequency synthesizer?

Select	Answer
A	The phase relationship between a voltage-controlled oscillator and the output waveform
B	The phase relationship between a reference oscillator and the output waveform
C	The amplitude values that represent a sine-wave output
D	The synthesizer frequency limits and frequency values stored in the radio memories

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 cosine wave
C	A sawtooth wave
D	A sine wave

39. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

Select	Answer
A	High speed digital modes
B	EME
C	OFDM signals are not allowed on amateur bands
D	Extremely low-power contacts

40. - E8C11

What is the relationship between symbol rate and baud?

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

41. - E8D01

Why are received spread spectrum signals resistant to interference?

Select	Answer
A	The receiver is always equipped with a digital blanker
B	If interference is detected by the receiver it will signal the transmitter to change frequencies
C	Signals not using the spread spectrum algorithm are suppressed in the receiver
D	The high power used by a spread spectrum transmitter keeps its signal from being easily overpowered

42. - E9A18

What term describes station output, taking into account all gains and losses?

Select	Answer
A	Apparent power
B	Half-power bandwidth
C	Effective radiated power
D	Power factor

43. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the 3 dB beam-width?

Select	Answer
A	30 degrees
B	75 degrees
C	50 degrees
D	25 degrees

44. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

Select	Answer
A	A Figure-8 broadside to the axis of the array
B	Omni-directional
C	Cardioid
D	A Figure-8 end-fire along the axis of the array

45. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

Select	Answer
A	To increase the SWR bandwidth
B	To lower the Q
C	To cancel capacitive reactance
D	To lower the losses

46. - E9E03

What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?

Select	Answer
A	The omega match
B	The stub match
C	The delta match
D	The gamma match

47. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically one-half wavelength long at 14.10 MHz?

Select	Answer
A	15 meters
B	10 meters
C	20 meters
D	71 meters

48. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

Select	Answer
A	Resistance and voltage
B	Voltage and impedance
C	Reactance and voltage
D	Resistance and reactance

49. - E9H06

What is the triangulation method of direction finding?

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

50. - E0A01

What is the primary function of an external earth connection or ground rod?

Select	Answer
A	Reduce received noise
B	Lightning protection
C	Reduce RF current flow between pieces of equipment
D	Reduce RFI to telephones and home entertainment systems

Figure E5-2

Figure E9-1