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

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1. - E1A10

If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?

Select	Answer
A	The amateur operator must have an FCC Marine or Aircraft endorsement on his or her amateur license
B	The amateur station must have a power supply that is completely independent of the main ship or aircraft power supply
C	Its operation must be approved by the master of the ship or the pilot in command of the aircraft
D	The amateur station operator must agree not to transmit when the main radio of the ship or aircraft is in use

2. - E1B02

Which of the following factors might cause the physical location of an amateur station apparatus or antenna structure to be restricted?

Select	Answer
A	The location is near an area of political conflict
B	The location is of geographical or horticultural importance
C	The location is in an ITU Zone designated for coordination with one or more foreign governments
D	The location is of environmental importance or significant in American history, architecture, or culture

3. - E1C06

Which of the following statements concerning remotely controlled amateur stations is true?

Select	Answer
A	A control operator need not be present at the control point
B	A control operator must be present at the control point
C	Only Extra Class operators may be the control operator of a remote station
D	Repeater and auxiliary stations may not be remotely controlled

4. - E1D02

What is the amateur satellite service?

Select	Answer
A	A radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
B	A radio communications service using amateur radio stations on satellites
C	A spacecraft launching service for amateur-built satellites
D	A radio communications service using stations on Earth satellites for public service broadcast

5. - E1E05

What is the minimum passing score on amateur operator license examinations?

Select	Answer
A	Minimum passing score of 77%
B	Minimum passing score of 74%
C	Minimum passing score of 70%
D	Minimum passing score of 80%

6. - E1F07

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

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

7. - E2A04

What is meant by the term mode as applied to an amateur radio satellite?

Select	Answer
A	The satellite's uplink and downlink frequency bands
B	The satellite's orientation with respect to the Earth
C	Whether the satellite is in a polar or equatorial orbit
D	The type of signals that can be relayed through the satellite

8. - E2B08

Which of the following is a common method of transmitting accompanying audio with amateur fast-scan television?

Select	Answer
A	Frequency modulation of the video carrier
B	A separate VHF or UHF audio link
C	All of these choices are correct
D	Frequency-modulated sub-carrier

9. - E2C04

What type of transmission is most often used for a ham radio mesh network?

Select	Answer
A	Multiple Frequency Shift Keying in the 10 GHz band
B	Spread spectrum in the 2.4 GHz band
C	Store and forward on the 440 MHz band
D	Frequency division multiplex in the 24 GHz band

10. - E2D06

Which of the following describes a method of establishing EME contacts?

Select	Answer
A	High speed CW identification to avoid fading
B	Time synchronous transmissions alternately from each station
C	Judging optimum transmission times by monitoring beacons reflected from the Moon
D	Storing and forwarding digital messages

11. - E2E13

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

Select	Answer
A	The protocol version you are using is not the supported by the digital station
B	Another station you are unable to hear is using the frequency
C	All of these choices are correct
D	Your transmit frequency is incorrect

12. - E3A09

Which of the following frequency range is most suited for meteor scatter communications?

Select	Answer
A	220 MHz - 450 MHz
B	10 MHz - 14 MHz
C	28 MHz - 148 MHz
D	1.8 MHz - 1.9 MHz

13. - E3B01

What is transequatorial propagation?

Select	Answer
A	Propagation between two stations at the same latitude
B	Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
C	Propagation between any two points located on the magnetic equator
D	Propagation between two continents by way of ducts along the magnetic equator

14. - E3C06

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

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

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

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

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	0.1 MHz
B	1.4652 kHz
C	14.652 Hz
D	1.4652 Hz

17. - E4C03

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

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

18. - E4D12

What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?

Select	Answer
A	Desensitization
B	Squelch gain rollback
C	Cross-modulation interference
D	Quieting

19. - E4E10

What is a common characteristic of interference caused by a touch controlled electrical device?

Select	Answer
A	The interfering signal can be several kHz in width and usually repeats at regular intervals across a HF band
B	All of these choices are correct
C	The interfering signal may drift slowly across the HF spectrum
D	The interfering signal sounds like AC hum on an AM receiver or a carrier modulated by 60 Hz hum on a SSB or CW receiver

20. - E5A17

What is the result of increasing the Q of an impedance-matching circuit?

Select	Answer
A	It has no effect on impedance matching
B	Matching range is increased
C	Matching bandwidth is increased
D	Matching bandwidth is decreased

21. - E5B03

What happens to the phase angle of a reactance when it is converted to a susceptance?

Select	Answer
A	It is shifted by 90 degrees
B	It is unchanged
C	The sign is reversed
D	The susceptance phase angle is the inverse of the reactance phase angle

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 7
C	Point 8
D	Point 3

23. - E5D14

What is reactive power?

Select	Answer
A	Power consumed in circuit Q
B	Power consumed in wire resistance in an inductor
C	Power lost because of capacitor leakage
D	Wattless, nonproductive power

24. - E6A16

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

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

25. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch or attenuator?

Select	Answer
A	Ability to dissipate large amounts of power
B	Extremely high reverse breakdown voltage
C	Reverse bias controls its forward voltage drop
D	A large region of intrinsic material

26. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	A device to control industrial equipment
B	A programmable collection of logic gates and circuits in a single integrated circuit
C	Programmable equipment used for testing digital logic integrated circuits
D	An algorithm for simulating logic functions during circuit design

27. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

Select	Answer
A	Ferrite beads
B	Butterworth filters
C	Steel-core toroids
D	Electrolytic capacitors

28. - E6E02

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

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

29. - E6F14

Which of the following is true of LCD displays?

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

30. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

Select	Answer
A	Astable multivibrator
B	Monostable multivibrator
C	T flip-flop
D	J-K 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 are relatively far in frequency from the desired signal
B	Because they invert the sidebands causing distortion
C	Because they maintain the sidebands, thus causing multiple duplicate signals
D	Because they are relatively close in frequency to the desired signal

32. - E7C06

What are the distinguishing features of an elliptical filter?

Select	Answer
A	Gradual passband rolloff with extreme stop band ripple
B	Extremely flat response over its pass band with gradually rounded stop band corners
C	Gradual passband rolloff with minimal stop band ripple
D	Extremely sharp cutoff with one or more notches in the stop band

33. - E7D13

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

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

34. - E7E09

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

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

35. - E7F14

Which of the following would allow a digital signal processing filter to create a sharper filter response?

Select	Answer
A	More taps
B	Higher data rate
C	Double-precision math routines
D	Complex phasor representations

36. - E7G02

What is the effect of ringing in a filter?

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

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

Select	Answer
A	NP0 capacitors
B	Wirewound resistors
C	Toroidal inductors
D	Non-inductive resistors

38. - E8A05

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

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

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

Select	Answer
A	Percentage of modulation
B	Quieting index
C	Modulation index
D	FM compressibility

40. - E8C03

When performing phase shift keying, why is it advantageous to shift phase precisely at the zero crossing of the RF carrier?

Select	Answer
A	It is easier to demodulate with a conventional, non-synchronous detector
B	It improves carrier suppression
C	All of these choices are correct
D	This results in the least possible transmitted bandwidth for the particular mode

41. - E8D09

What is considered a good minimum IMD level for an idling PSK signal?

Select	Answer
A	-20 dB
B	-30 dB
C	+15 dB
D	+10 dB

42. - E9A06

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

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

43. - E9B07

How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from an isotropic antenna, assuming each is driven by the same amount of power?

Select	Answer
A	The radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna
B	The total amount of radiation from the directional antenna is stronger by its front-to-back ratio
C	The total amount of radiation from the directional antenna is increased by the gain of the antenna
D	They are the same

44. - E9C02

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

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

45. - E9D10

What happens to feed point impedance at the base of a fixed length HF mobile antenna as the frequency of operation is lowered?

Select	Answer
A	The radiation resistance increases and the capacitive reactance decreases
B	The radiation resistance decreases and the capacitive reactance decreases
C	The radiation resistance decreases and the capacitive reactance increases
D	The radiation resistance increases and the capacitive reactance increases

46. - E9E09

Which of these matching systems is an effective method of connecting a 50 ohm coaxial cable feed line to a grounded tower so it can be used as a vertical antenna?

Select	Answer
A	Gamma match
B	Double-bazooka match
C	All of these choices are correct
D	Hairpin match

47. - E9F09

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 7.2 MHz?

Select	Answer
A	6.9 meters
B	50 meters
C	10 meters
D	24 meters

48. - E9G10

What do the arcs on a Smith chart represent?

Select	Answer
A	Points with constant resistance
B	Frequency
C	SWR
D	Points with constant reactance

49. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	All of these choices are correct
B	Low loss coax transmission line is essential for good performance
C	Atmospheric noise is so high that gain over a dipole is not important
D	They must be erected at least 1/2 wavelength above the ground to attain good directivity

50. - E0A10

What toxic material may be present in some electronic components such as high voltage capacitors and transformers?

Select	Answer
A	Polychlorinated Biphenyls
B	Polyethylene
C	Polymorphic silicon
D	Polytetrafluroethylene

Figure E5-2