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

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1. - E1A01

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the highest frequency at which a properly adjusted USB emission will be totally within the band?

Select	Answer
A	1 kHz below the upper band edge
B	The exact upper band edge
C	300 Hz below the upper band edge
D	3 kHz below the upper band edge

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

3. - E1C05

When may an automatically controlled station originate third party communications?

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

4. - E1D03

What is a telecommand station in the amateur satellite service?

Select	Answer
A	An amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites
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 that transmits communications to initiate, modify or terminate functions of a space station

5. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

Select	Answer
A	Revocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
B	A fine of up to $1000 per occurrence
C	All of these choices are correct
D	A sentence of up to one year in prison

6. - E1F08

Which of the following types of amateur station communications are prohibited?

Select	Answer
A	Communications that have a political content, except as allowed by the Fairness Doctrine
B	Communications in a language other than English
C	Communications that have a religious content
D	Communications transmitted for hire or material compensation, except as otherwise provided in the rules

7. - E2A05

What do the letters in a satellite's mode designator specify?

Select	Answer
A	The uplink and downlink frequency ranges
B	The location of the ground control station
C	The polarization of uplink and downlink signals
D	Power limits for uplink and downlink transmissions

8. - E2B02

How many horizontal lines make up a fast-scan (NTSC) television frame?

Select	Answer
A	525
B	30
C	60
D	1080

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

Select	Answer
A	The acceptable practice of manually posting the call signs of stations on a spotting network
B	The generally prohibited practice of posting one's own call sign and frequency on a spotting network
C	An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
D	A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station

10. - E2D06

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

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

11. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

Select	Answer
A	PSK31
B	MT63
C	PACTOR
D	RTTY

12. - E3A10

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

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

13. - E3B12

What is the primary characteristic of chordal hop propagation?

Select	Answer
A	Propagation away from the great circle bearing between stations
B	Propagation across the geomagnetic equator
C	Successive ionospheric reflections without an intermediate reflection from the ground
D	Signals reflected back toward the transmitting station

14. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

Select	Answer
A	Transequatorial propagation
B	Polar paths
C	NVIS
D	Sporadic-E

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 frequency standard is displayed and the probe is adjusted until the deflection time is accurate
C	A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude
D	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate

16. - E4B10

Which of the following describes a method to measure intermodulation distortion in an SSB transmitter?

Select	Answer
A	Modulate the transmitter with two harmonically related audio frequencies and observe the RF output with a peak reading wattmeter
B	Modulate the transmitter with two non-harmonically related radio frequencies and observe the RF output with a spectrum analyzer
C	Modulate the transmitter with two harmonically related audio frequencies and observe the RF output with a logic analyzer
D	Modulate the transmitter with two non-harmonically related audio frequencies and observe the RF output with a spectrum analyzer

17. - E4C08

An SDR receiver is overloaded when input signals exceed what level?

Select	Answer
A	The maximum count value of the analog-to-digital converter
B	The reference voltage of the analog-to-digital converter
C	One-half the maximum sample rate
D	One-half the maximum sampling buffer size

18. - E4D12

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

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

19. - E4E04

How can conducted and radiated noise caused by an automobile alternator be suppressed?

Select	Answer
A	By connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads
B	By installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead
C	By installing a noise suppression resistor and a blocking capacitor in both leads
D	By installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead

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	218.3 kHz
B	31.4 kHz
C	15.7 kHz
D	436.6 kHz

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

22. - E5C12

If you plot the impedance of a circuit using the rectangular coordinate system and find the impedance point falls on the right side of the graph on the horizontal axis, what do you know about the circuit?

Select	Answer
A	It contains resistance and capacitive reactance
B	It has to be a direct current circuit
C	It contains resistance and inductive reactance
D	It is equivalent to a pure resistance

23. - E5D14

What is reactive power?

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

24. - E6A10

In Figure E6-2, what is the schematic symbol for an N-channel dual-gate MOSFET?

Select	Answer
A	5
B	6
C	4
D	2

25. - E6B09

What is a common use for point contact diodes?

Select	Answer
A	As a constant current source
B	As a high voltage rectifier
C	As an RF detector
D	As a constant voltage source

26. - E6C12

What is BiCMOS logic?

Select	Answer
A	A logic device with two CMOS circuits per package
B	A FET logic family based on bimetallic semiconductors
C	A logic family based on bismuth CMOS devices
D	An integrated circuit logic family using both bipolar and CMOS transistors

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	Excitation current
C	Stabilizing current
D	Magnetizing current

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	Nearly infinite gain, very high input impedance, and very low output impedance
C	Plate current that is controlled by a control grid
D	The ability to retrieve information from a single signal even in the presence of other strong signals

29. - E6F07

What is a solid state relay?

Select	Answer
A	A passive delay line
B	A relay using transistors to drive the relay coil
C	A device that uses semiconductors to implement the functions of an electromechanical relay
D	A mechanical relay that latches in the on or off state each time it is pulsed

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	J-K flip-flop
D	T flip-flop

31. - E7B08

How can an RF power amplifier be neutralized?

Select	Answer
A	By feeding a 180-degree out-of-phase portion of the output back to the input
B	By reducing the driving power
C	By increasing the driving power
D	By feeding an in-phase component of the output back to the input

32. - E7C15

What is a crystal lattice filter?

Select	Answer
A	A filter with narrow bandwidth and steep 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 wide bandwidth and shallow skirts made using quartz crystals

33. - E7D02

What is one characteristic of a switching electronic voltage regulator?

Select	Answer
A	The controlled device's duty cycle is changed to produce a constant average output voltage
B	It is generally less efficient than a linear regulator
C	The resistance of a control element is varied in direct proportion to the line voltage or load current
D	It gives a ramp voltage at its output

34. - E7E07

What is meant by the term baseband in radio communications?

Select	Answer
A	The frequency components present in the modulating signal
B	The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
C	The lowest frequency band that the transmitter or receiver covers
D	The unmodulated bandwidth of the transmitted signal

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	4 bits
B	10 bits
C	6 bits
D	8 bits

36. - E7G02

What is the effect of ringing in a filter?

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

37. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

Select	Answer
A	Pierce and Zener
B	Armstrong and deForest
C	Negative feedback and balanced feedback
D	Colpitts and Hartley

38. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

Select	Answer
A	2.5 to 1
B	100 to 1
C	1 to 1
D	25 to 1

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	The transmitted signal is divided into packets of information
B	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
C	The transmitted signal jumps from band to band at a predetermined rate
D	Two or more information streams are merged into a baseband, which then modulates the transmitter

40. - E8C06

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

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

41. - E8D08

What parameter might indicate that excessively high input levels are causing distortion in an AFSK signal?

Select	Answer
A	Intermodulation Distortion (IMD)
B	Baud rate
C	Signal to noise ratio
D	Repeat Request Rate (RRR)

42. - E9A13

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 12 dB gain over an isotropic antenna?

Select	Answer
A	6.17 dB
B	14.15 dB
C	12.5 dB
D	9.85 dB

43. - E9B06

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

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

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

Select	Answer
A	It changes the impedance angle of the matching network
B	It causes increased SWR
C	It reduces losses in the radiating portion of the antenna
D	It reduces low-angle radiation

45. - E9D13

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

Select	Answer
A	The front-to-back ratio decreases
B	The frequency response is widened over the whole frequency band
C	The front-to-back ratio increases
D	The SWR is reduced

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

Select	Answer
A	Connect a parallel-resonant LC network across the antenna feed terminals
B	Use a 50 ohm 1:1 balun between the antenna and feed line
C	Use the universal stub matching technique
D	Connect a series-resonant LC network across the antenna feed terminals

47. - E9F03

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

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

48. - E9G03

Which of the following is often determined using a Smith chart?

Select	Answer
A	Impedance and SWR values in transmission lines
B	Beam headings and radiation patterns
C	Satellite azimuth and elevation bearings
D	Trigonometric functions

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	The geometric angles of sky waves from the source are used to determine its position
D	A fixed receiving station plots three headings to the signal source

50. - E0A10

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

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

Figure E6-2

Figure E9-2