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

2. - E1B05

What is the National Radio Quiet Zone?

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

3. - E1C06

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

Select	Answer
A	Repeater and auxiliary stations may not be remotely controlled
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	A control operator need not be present at the control point

4. - E1D06

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

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

5. - E1E08

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

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

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 the total money involved does not exceed $25
D	When transmitting international third-party communications

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

Select	Answer
A	APRS
B	Doppler shift of beacon signals
C	Radar
D	Bandwidth compressed LORAN

8. - E2B05

Which of the following is an advantage of using vestigial sideband for standard fast- scan TV transmissions?

Select	Answer
A	The vestigial sideband carries the audio information
B	Vestigial sideband reduces bandwidth while allowing for simple video detector circuitry
C	Vestigial sideband provides high frequency emphasis to sharpen the picture
D	The vestigial sideband contains chroma information

9. - E2C09

What type of equipment is commonly used to implement a ham radio mesh network?

Select	Answer
A	A standard wireless router running custom software
B	An optical cable connection between the USB ports of 2 separate computers
C	A 2 meter VHF transceiver with a 1200 baud modem
D	A 440 MHz transceiver with a 9600 baud modem

10. - E2D14

What is one advantage of using JT65 coding?

Select	Answer
A	Uses only a 65 Hz bandwidth
B	Permits fast-scan TV transmissions over narrow bandwidth
C	Easily copied by ear if necessary
D	The ability to decode signals which have a very low signal to noise ratio

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

Select	Answer
A	First Error Correction
B	Final Error Correction
C	Fatal Error Correction
D	Forward Error Correction

12. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

Select	Answer
A	When the Moon is at perigee
B	When the Moon is full
C	When the Moon is at apogee
D	When the MUF is above 30 MHz

13. - E3B04

What is meant by the terms extraordinary and ordinary waves?

Select	Answer
A	Independent waves created in the ionosphere that are elliptically polarized
B	Extraordinary waves describe rare long skip propagation compared to ordinary waves which travel shorter distances
C	Long path and short path waves
D	Refracted rays and reflected waves

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. - E4A04

What determines the upper frequency limit for a computer soundcard-based oscilloscope program?

Select	Answer
A	Q of the interface of the interface circuit
B	Amount of memory on the soundcard
C	All of these choices are correct
D	Analog-to-digital conversion speed of the soundcard

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

Select	Answer
A	High reluctance input
B	Low reluctance input
C	High impedance input
D	Low impedance input

17. - E4C03

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

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

18. - E4D07

Which describes the most significant effect of an off-frequency signal when it is causing cross-modulation interference to a desired signal?

Select	Answer
A	The desired signal can no longer be heard
B	A large increase in background noise
C	A reduction in apparent signal strength
D	The off-frequency unwanted signal is heard in addition to the desired signal

19. - E4E13

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

Select	Answer
A	All of these choices are correct
B	A malfunctioning illuminated advertising display
C	A defective doorbell or doorbell transformer inside a nearby residence
D	Arcing contacts in a thermostatically controlled device

20. - E5A06

What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

Select	Answer
A	It equals 1 divided by the quantity 2 times Pi, multiplied by the square root of inductance L multiplied by capacitance C
B	It equals 2 multiplied by Pi, multiplied by frequency, multiplied by inductance
C	It is at a minimum
D	It is at a maximum

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

Select	Answer
A	440 seconds
B	55 seconds
C	110 seconds
D	220 seconds

22. - E5C14

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 400 ohm resistor and a 38 picofarad capacitor at 14 MHz?

Select	Answer
A	Point 6
B	Point 5
C	Point 2
D	Point 4

23. - E5D12

How many watts are consumed in a circuit having a power factor of 0.2 if the input is 100-VAC at 4 amperes?

Select	Answer
A	80 watts
B	2000 watts
C	400 watts
D	50 watts

24. - E6A09

What is a depletion-mode FET?

Select	Answer
A	An FET that exhibits a current flow between source and drain when no gate voltage is applied
B	Any FET for which holes are the majority carriers
C	An FET that has no current flow between source and drain when no gate voltage is applied
D	Any FET without a channel

25. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

Select	Answer
A	Tunnel diode
B	Varactor diode
C	Zener diode
D	Silicon-controlled rectifier

26. - E6C01

What is the function of hysteresis in a comparator?

Select	Answer
A	To increase the sensitivity
B	To prevent input noise from causing unstable output signals
C	To allow the comparator to be used with AC input signal
D	To cause the output to change states continually

27. - E6D06

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

Select	Answer
A	Permeability
B	Resistance
C	Reactivity
D	Thermal impedance

28. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

Select	Answer
A	A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
B	Package mounts in a direct inverted position
C	Low leakage doubly insulated package
D	Two chips in each package (Dual In Package)

29. - E6F09

What is the efficiency of a photovoltaic cell?

Select	Answer
A	The relative fraction of light that is converted to current
B	The effective payback period
C	The output RF power divided by the input DC power
D	The open-circuit voltage divided by the short-circuit current under full illumination

30. - E7A12

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

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

31. - E7B15

What is one way to prevent thermal runaway in a bipolar transistor amplifier?

Select	Answer
A	All of these choices are correct
B	Select transistors with high beta
C	Use a resistor in series with the emitter
D	Neutralization

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

Select	Answer
A	Cascode
B	Omega
C	Pi-L
D	Pi

33. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

Select	Answer
A	A shunt regulator
B	A shunt current source
C	A series current source
D	A series regulator

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 reactance modulator on the final amplifier
D	A balanced modulator on the audio amplifier

35. - E7F11

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

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

36. - E7G02

What is the effect of ringing in a filter?

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

37. - E7H14

What is a phase-locked loop circuit?

Select	Answer
A	An electronic circuit also known as a monostable multivibrator
B	An electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
C	An electronic circuit consisting of a precision push-pull amplifier with a differential input
D	An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator

38. - E8A11

What type of information can be conveyed using digital waveforms?

Select	Answer
A	Video signals
B	Data
C	Human speech
D	All of these choices are correct

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	2000
B	1/3
C	6000
D	3

40. - E8C04

What technique is used to minimize the bandwidth requirements of a PSK31 signal?

Select	Answer
A	Zero-sum character encoding
B	Reed-Solomon character encoding
C	Use of sinusoidal data pulses
D	Use of trapezoidal data pulses

41. - E8D08

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

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

42. - E9A11

Which of the following factors determines ground losses for a ground-mounted vertical antenna operating in the 3 MHz to 30 MHz range?

Select	Answer
A	The standing wave ratio
B	Soil conductivity
C	Take-off angle
D	Distance from the transmitter

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

Select	Answer
A	Elevation
B	Polarization
C	Radiation resistance
D	Azimuth

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

45. - E9D13

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

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

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	A series capacitor
C	Pi-L-network
D	A shunt inductor

47. - E9F16

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

Select	Answer
A	All of these choices are correct
B	Foam dielectric has higher velocity factor
C	Foam dielectric has lower loss per unit of length
D	Foam dielectric has lower safe operating voltage limits

48. - E9G03

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

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

49. - E9H02

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

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

50. - E0A08

What does SAR measure?

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

Figure E5-2

Figure E9-2