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

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1. - E1A02

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

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

2. - E1B05

What is the National Radio Quiet Zone?

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

3. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

Select	Answer
A	Under automatic control there is no control operator
B	Under local control there is no control operator
C	Under local control a control operator is not required to be present at a control point
D	Under automatic control the control operator is not required to be present at the control point

4. - E1D04

What is an Earth station in the amateur satellite service?

Select	Answer
A	An amateur station within 50 km of the Earth's surface intended for communications with amateur stations by means of objects in space
B	An amateur station that transmits telemetry consisting of measurement of upper atmosphere
C	An amateur station that is not able to communicate using amateur satellites
D	Any amateur station on the surface of the Earth

5. - E1E11

What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

Select	Answer
A	All these choices are correct
B	Three VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
C	Issue the examinee the new or upgrade license
D	Photocopy all examination documents and forward them to the FCC for processing

6. - E1F07

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

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

7. - E2A13

What type of satellite appears to stay in one position in the sky?

Select	Answer
A	Geostationary
B	Geomagnetic
C	LEO
D	HEO

8. - E2B17

What is the approximate bandwidth of a slow-scan TV signal?

Select	Answer
A	3 kHz
B	600 Hz
C	2 MHz
D	6 MHz

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	A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
D	An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station

10. - E2D11

Which of the following data are used by the APRS network to communicate your location?

Select	Answer
A	Latitude and longitude
B	Polar coordinates
C	Time and frequency
D	Radio direction finding spectrum analysis

11. - E2E06

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

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

12. - E3A02

What characterizes libration fading of an EME signal?

Select	Answer
A	The returning echo is several Hertz lower in frequency than the transmitted signal
B	A gradual loss of signal as the Sun rises
C	A slow change in the pitch of the CW signal
D	A fluttery irregular fading

13. - E3B10

What is the cause of gray-line propagation?

Select	Answer
A	At midday, the Sun super heats the ionosphere causing increased refraction of radio waves
B	At mid-afternoon, the Sun heats the ionosphere decreasing radio wave refraction and the MUF
C	In darkness, solar absorption drops greatly while atmospheric ionization remains steady
D	At twilight and sunrise, D-layer absorption is low while E-layer and F-layer propagation remains high

14. - E3C13

What type of polarization is best for ground-wave propagation?

Select	Answer
A	Horizontal
B	Circular
C	Vertical
D	Elliptical

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	Analog-to-digital conversion speed of the soundcard
C	Amount of memory on the soundcard
D	All of these choices are correct

16. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

Select	Answer
A	100 watts
B	125 watts
C	25 watts
D	75 watts

17. - E4C04

How is the noise figure of a receiver defined?

Select	Answer
A	The ratio of atmospheric noise to phase noise
B	The ratio in dB of the noise generated by the receiver to the theoretical minimum noise
C	The ratio of thermal noise to atmospheric noise
D	The ratio of the noise bandwidth in Hertz to the theoretical bandwidth of a resistive network

18. - E4D12

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

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

19. - E4E03

Which of the following signals might a receiver noise blanker be able to remove from desired signals?

Select	Answer
A	Signals which have a sharply peaked frequency distribution
B	Signals which are constant at all IF levels
C	Signals which appear across a wide bandwidth
D	Signals which appear at one IF but not another

20. - E5A13

What is an effect of increasing Q in a resonant circuit?

Select	Answer
A	Parasitic effects are minimized
B	Fewer components are needed for the same performance
C	Phase shift can become uncontrolled
D	Internal voltages and circulating currents increase

21. - E5B09

What is the relationship between the current through a capacitor and the voltage across a capacitor?

Select	Answer
A	Current leads voltage by 90 degrees
B	Voltage and current are 180 degrees out of phase
C	Voltage leads current by 90 degrees
D	Voltage and current are in phase

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 7
B	Point 1
C	Point 3
D	Point 8

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	1000 watts
B	1600 watts
C	200 watts
D	600 watts

24. - E6A10

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

Select	Answer
A	5
B	2
C	4
D	6

25. - E6B06

Which of the following is a common use of a hot-carrier diode?

Select	Answer
A	As a VHF/UHF mixer or detector
B	As balanced mixers in FM generation
C	As a variable capacitance in an automatic frequency control circuit
D	As a constant voltage reference in a power supply

26. - E6C04

What is the primary advantage of tri-state logic?

Select	Answer
A	Low power consumption
B	High speed operation
C	Ability to connect many device outputs to a common bus
D	More efficient arithmetic operations

27. - E6D15

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

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

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

Select	Answer
A	Ground-plane construction
B	Wave-soldering construction
C	Microstrip construction
D	Point-to-point construction

29. - E6F03

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

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

30. - E7A10

What is a truth table?

Select	Answer
A	A table of logic symbols that indicate the high logic states of an op-amp
B	A table of logic symbols that indicate the logic states of an op-amp
C	A diagram showing logic states when the digital device output is true
D	A list of inputs and corresponding outputs for a digital device

31. - E7B03

Which of the following components form the output of a class D amplifier circuit?

Select	Answer
A	A matched load resistor to prevent damage by switching transients
B	A high-pass filter to compensate for low gain at low frequencies
C	A low-pass filter to remove switching signal components
D	A temperature compensating load resistor to improve linearity

32. - E7C15

What is a crystal lattice filter?

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

33. - E7D06

What is the purpose of Q1 in the circuit shown in Figure E7-3?

Select	Answer
A	It provides negative feedback to improve regulation
B	It increases the current-handling capability of the regulator
C	It provides D1 with current
D	It provides a constant load for the voltage source

34. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

Select	Answer
A	1.414 and 0.707 times the input frequency
B	The sum, difference and square root of the input frequencies
C	Two and four times the original frequency
D	The two input frequencies along with their sum and difference frequencies

35. - E7F14

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

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

36. - E7G06

Which of the following is the most appropriate use of an op-amp active filter?

Select	Answer
A	As a low-pass filter used between a transmitter and a transmission line
B	As an audio filter in a receiver
C	As a high-pass filter used to block RFI at the input to receivers
D	For smoothing power supply output

37. - E7H15

Which of these functions can be performed by a phase-locked loop?

Select	Answer
A	Comparison of two digital input signals, digital pulse counter
B	Photovoltaic conversion, optical coupling
C	Wide-band AF and RF power amplification
D	Frequency synthesis, FM demodulation

38. - E8A12

What is an advantage of using digital signals instead of analog signals to convey the same information?

Select	Answer
A	Less complex circuitry is required for digital signal generation and detection
B	Digital signals can be regenerated multiple times without error
C	Digital signals always occupy a narrower bandwidth
D	All of these choices are correct

39. - E8B02

How does the modulation index of a phase-modulated emission vary with RF carrier frequency (the modulated frequency)?

Select	Answer
A	It increases as the RF carrier frequency increases
B	It varies with the square root of the RF carrier frequency
C	It does not depend on the RF carrier frequency
D	It decreases as the RF carrier frequency increases

40. - E8C04

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

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

41. - E8D11

What is one advantage of using ASCII code for data communications?

Select	Answer
A	It is possible to transmit both upper and lower case text
B	It contains fewer information bits per character than any other code
C	It uses one character as a shift code to send numeric and special characters
D	It includes built in error correction features

42. - E9A18

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

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

43. - E9B14

What type of information can be obtained by submitting the details of a proposed new antenna to a modeling program?

Select	Answer
A	Polar plots of the far field elevation and azimuth patterns
B	All of these choices are correct
C	Antenna gain
D	SWR vs frequency charts

44. - E9C08

What is a folded dipole antenna?

Select	Answer
A	A dipole configured to provide forward gain
B	A dipole consisting of one wavelength of wire forming a very thin loop
C	A dipole one-quarter wavelength long
D	A type of ground-plane antenna

45. - E9D06

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

Select	Answer
A	It becomes flat
B	No change occurs
C	It is decreased
D	It is increased

46. - E9E08

Which of the following measurements is characteristic of a mismatched transmission line?

Select	Answer
A	A dielectric constant greater than 1
B	An SWR greater than 1:1
C	A reflection coefficient greater than 1
D	An SWR less than 1:1

47. - E9F01

What is the velocity factor of a transmission line?

Select	Answer
A	The velocity of the wave in the transmission line divided by the velocity of light in a vacuum
B	The velocity of the wave in the transmission line multiplied by the velocity of light in a vacuum
C	The ratio of the characteristic impedance of the line to the terminating impedance
D	The index of shielding for coaxial cable

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 voltage axis
D	The current axis

49. - E9H02

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

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

50. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Advise your neighbors of the results of your tests
B	You need only evaluate exposure levels on your own property
C	Make sure signals from your station are less than the controlled MPE limits
D	Make sure signals from your station are less than the uncontrolled MPE limits

Figure E5-2

Figure E6-2

Figure E7-3

Figure E9-3