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

2. - E1B07

What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

Select	Answer
A	3.0
B	2.0
C	1.0
D	0.5

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 automatic control the control operator is not required to be present at the control point
D	Under local control a control operator is not required to be present at a control point

4. - E1D03

What is a telecommand station in the amateur satellite service?

Select	Answer
A	An amateur station located more than 50 km above the Earth's surface
B	An amateur station that transmits communications to initiate, modify or terminate functions of a space station
C	An amateur station located on the Earth's surface for communication with other Earth stations by means of Earth satellites
D	An amateur station that transmits telemetry consisting of measurements of upper atmosphere

5. - E1E03

What is a Volunteer Examiner Coordinator?

Select	Answer
A	An organization that has entered into an agreement with the FCC to coordinate amateur operator license examinations
B	A person who has volunteered to administer amateur operator license examinations
C	A person who has volunteered to prepare amateur operator license examinations
D	The person who has entered into an agreement with the FCC to be the VE session manager

6. - E1F10

What is the maximum permitted transmitter peak envelope power for an amateur station transmitting spread spectrum communications?

Select	Answer
A	1.5 W
B	1 W
C	1.5 kW
D	10 W

7. - E2A06

On what band would a satellite receive signals if it were operating in mode U/V?

Select	Answer
A	29.5 MHz - 29.7 MHz
B	144 MHz - 146 MHz
C	50.0 MHz - 50.2 MHz
D	435 MHz - 438 MHz

8. - E2B15

What signals SSTV receiving equipment to begin a new picture line?

Select	Answer
A	Specific tone frequencies
B	Specific tone amplitudes
C	A two-tone signal
D	Elapsed time

9. - E2C10

Why might a DX station state that they are listening on another frequency?

Select	Answer
A	All of these choices are correct
B	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations
C	To improve operating efficiency by reducing interference
D	To separate the calling stations from the DX station

10. - E2D09

Which of these digital modes has the fastest data throughput under clear communication conditions?

Select	Answer
A	AMTOR
B	300 baud packet
C	170 Hz shift, 45 baud RTTY
D	PSK31

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. - E3A04

What do Hepburn maps predict?

Select	Answer
A	Sporadic E propagation
B	Probability of tropospheric propagation
C	Likelihood of rain-scatter along cold or warm fronts
D	Locations of auroral reflecting zones

13. - E3B12

What is the primary characteristic of chordal hop propagation?

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

14. - E3C06

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

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

15. - E4A14

What is the purpose of the prescaler function on a frequency counter?

Select	Answer
A	It multiplies a higher frequency signal so a low-frequency counter can display the operating frequency
B	It prevents oscillation in a low-frequency counter circuit
C	It divides a higher frequency signal so a low-frequency counter can display the input frequency
D	It amplifies low level signals for more accurate counting

16. - E4B07

What do the subscripts of S parameters represent?

Select	Answer
A	The port or ports at which measurements are made
B	Relative quality of the data
C	The relative time between measurements
D	Frequency order of the measurements

17. - E4C11

Which of the following is a desirable amount of selectivity for an amateur SSB phone receiver?

Select	Answer
A	4.2 kHz
B	1 kHz
C	2.4 kHz
D	4.8 kHz

18. - E4D05

What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

Select	Answer
A	146.34 MHz and 146.61 MHz
B	173.35 MHz and 139.40 MHz
C	146.10 MHz and 147.30 MHz
D	146.88 MHz and 146.34 MHz

19. - E4E02

Which of the following types of receiver noise can often be reduced with a DSP noise filter?

Select	Answer
A	Power line noise
B	Broadband white noise
C	All of these choices are correct
D	Ignition noise

20. - E5A05

What is the magnitude of the current at the input of a series RLC circuit as the frequency goes through resonance?

Select	Answer
A	L/R
B	Maximum
C	R/L
D	Minimum

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	68.2 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	14.0 degrees with the voltage leading 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 1
B	Point 8
C	Point 3
D	Point 7

23. - E5D07

What determines the strength of the magnetic field around a conductor?

Select	Answer
A	The amount of current flowing through the conductor
B	The diameter of the conductor
C	The ratio of the current to the resistance
D	The resistance divided by the current

24. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

Select	Answer
A	Corner frequency
B	Alpha cutoff frequency
C	Beta cutoff frequency
D	Alpha rejection frequency

25. - E6B13

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

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

26. - E6C14

What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?

Select	Answer
A	Complex logic functions can be created in a single integrated circuit
B	All of these choices are correct
C	A PGA contains its own internal power supply
D	Many similar gates are less expensive than a mixture of gate types

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

28. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

Select	Answer
A	10 ohms
B	50 ohms
C	300 ohms
D	450 ohms

29. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

Select	Answer
A	It stays the same
B	It becomes unstable
C	It decreases
D	It increases

30. - E7A09

What logical operation is performed by an exclusive NOR gate?

Select	Answer
A	It produces logic "1" at its output if any single input is logic "1"
B	It produces logic "0" at its output if any single input is logic "1"
C	It produces logic "1" at its output only if all inputs are logic "1"
D	It produces logic "0" at its output only if all inputs are logic "0"

31. - E7B11

In Figure E7-1, what is the purpose of R3?

Select	Answer
A	Emitter bypass
B	Self bias
C	Output load resistor
D	Fixed bias

32. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

Select	Answer
A	A Butterworth filter
B	An active LC filter
C	A Chebyshev filter
D	A passive op-amp filter

33. - E7D03

What device is typically used as a stable reference voltage in a linear voltage regulator?

Select	Answer
A	A varactor diode
B	An SCR
C	A tunnel diode
D	A Zener diode

34. - E7E04

What is one way a single-sideband phone signal can be generated?

Select	Answer
A	By using a loop modulator followed by a mixer
B	By using a balanced modulator followed by a filter
C	By driving a product detector with a DSB signal
D	By using a reactance modulator followed by a mixer

35. - E7F10

What aspect of receiver analog-to-digital conversion determines the maximum receive bandwidth of a Direct Digital Conversion SDR?

Select	Answer
A	Sample width in bits
B	Sample clock phase noise
C	Sample rate
D	Processor latency

36. - E7G12

What is an integrated circuit operational amplifier?

Select	Answer
A	A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance
B	An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit
C	A digital audio amplifier whose characteristics are determined by components external to the amplifier
D	A RF amplifier used in the UHF and microwave regions

37. - E7H15

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

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

38. - E8A02

What type of wave has a rise time significantly faster than its fall time (or vice versa)?

Select	Answer
A	A square wave
B	A sine wave
C	A sawtooth wave
D	A cosine wave

39. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

Select	Answer
A	0.6
B	1.67
C	0.167
D	60

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

41. - E8D08

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

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

42. - E9A04

Which of the following factors may affect the feed point impedance of an antenna?

Select	Answer
A	The settings of an antenna tuner at the transmitter
B	Transmission-line length
C	Sunspot activity and time of day
D	Antenna height, conductor length/diameter ratio and location of nearby conductive objects

43. - E9B13

What does the abbreviation NEC stand for when applied to antenna modeling programs?

Select	Answer
A	Numerical Electromagnetic Code
B	Next Element Comparison
C	Numeric Electrical Computation
D	National Electrical Code

44. - E9C15

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with its height above ground?

Select	Answer
A	The main lobe takeoff angle increases with increasing height
B	The main lobe takeoff angle decreases with increasing height
C	The horizontal beam width decreases with height
D	The horizontal beam width increases with height

45. - E9D11

Which of the following types of conductors would be best for minimizing losses in a station's RF ground system?

Select	Answer
A	A single 12 gauge or 10 gauge stainless steel wire
B	A wide flat copper strap
C	A resistive wire, such as spark plug wire
D	A cable with six or seven 18 gauge conductors in parallel

46. - E9E07

What term best describes the interactions at the load end of a mismatched transmission line?

Select	Answer
A	Reflection coefficient
B	Characteristic impedance
C	Velocity factor
D	Dielectric constant

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	24 meters
B	10 meters
C	50 meters
D	6.9 meters

48. - E9G10

What do the arcs on a Smith chart represent?

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

49. - E9H08

What is the function of a sense antenna?

Select	Answer
A	It modifies the pattern of a DF antenna array to provide a null in one direction
B	It provides diversity reception that cancels multipath signals
C	It allows DF antennas to receive signals at different vertical angles
D	It increases the sensitivity of a DF antenna array

50. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Select	Answer
A	Each transmitter operating with a duty-cycle greater than 50 percent
B	Only commercial transmitters
C	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations
D	Only the most powerful transmitter

Figure E5-2

Figure E7-1