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

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E1A14

What is the maximum bandwidth for a data emission on 60 meters?

Select	Answer
A	2.8 kHz
B	60 Hz
C	170 Hz
D	1.5 kHz

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

3. - E1C04

What is meant by IARP?

Select	Answer
A	A forecast of intermittent aurora radio propagation
B	The internal amateur radio practices policy of the FCC
C	An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
D	An indication of increased antenna reflected power

4. - E1D01

What is the definition of the term telemetry?

Select	Answer
A	Two-way single channel transmissions of data
B	One-way transmission that initiates, modifies, or terminates the functions of a device at a distance
C	Two-way radiotelephone transmissions in excess of 1000 feet
D	One-way transmission of measurements at a distance from the measuring instrument

5. - E1E06

Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

Select	Answer
A	The VEC coordinating the session
B	The FCC
C	Each administering VE
D	The VE session manager

6. - E1F12

Who may be the control operator of an auxiliary station?

Select	Answer
A	Only Amateur Extra Class operators
B	Only General, Advanced or Amateur Extra Class operators
C	Any licensed amateur operator
D	Only Technician, General, Advanced or Amateur Extra Class operators

7. - E2A09

What do the terms L band and S band specify with regard to satellite communications?

Select	Answer
A	FM and Digital Store-and-Forward systems
B	Which sideband to use
C	The 2 meter and 70 centimeter bands
D	The 23 centimeter and 13 centimeter bands

8. - E2B02

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

Select	Answer
A	30
B	60
C	525
D	1080

9. - E2C03

From which of the following bands is amateur radio contesting generally excluded?

Select	Answer
A	6 m
B	30 m
C	2 m
D	33 cm

10. - E2D09

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

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

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

Select	Answer
A	300-baud packet
B	MFSK16
C	170 Hz shift, 45 baud RTTY
D	PSK31

12. - E3A15

What is an electromagnetic wave?

Select	Answer
A	A wave consisting of two electric fields at parallel right angles to each other
B	A wave of alternating current, in the core of an electromagnet
C	A wave consisting of two magnetic fields at right angles to each other
D	A wave consisting of an electric field and a magnetic field oscillating at right angles to each other

13. - E3B10

What is the cause of gray-line propagation?

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

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

Select	Answer
A	It increases
B	It decreases
C	It peaks at roughly 14 MHz
D	It stays the same

15. - E4A06

What is the effect of aliasing in a digital or computer-based oscilloscope?

Select	Answer
A	All signals will have a DC offset
B	False triggering occurs
C	False signals are displayed
D	Calibration of the vertical scale is no longer valid

16. - E4B17

What three test loads are used to calibrate a standard RF vector network analyzer?

Select	Answer
A	Short circuit, open circuit, and resonant circuit
B	50 ohms, 75 ohms, and 90 ohms
C	50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable
D	Short circuit, open circuit, and 50 ohms

17. - E4C04

How is the noise figure of a receiver defined?

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

18. - E4D11

Why are third-order intermodulation products created within a receiver of particular interest compared to other products?

Select	Answer
A	The third-order product of two signals which are in the band of interest is also likely to be within the band
B	The third-order intercept is much higher than other orders
C	Third-order intermodulation produces three products for every input signal within the band of interest
D	Third-order products are an indication of poor image rejection

19. - E4E01

Which of the following types of receiver noise can often be reduced by use of a receiver noise blanker?

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

20. - E5A02

What is resonance in an electrical circuit?

Select	Answer
A	The highest frequency that will pass current
B	The lowest frequency that will pass current
C	The frequency at which the capacitive reactance equals the inductive reactance
D	The frequency at which the reactive impedance equals the resistive impedance

21. - E5B05

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

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

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 3
B	Point 8
C	Point 1
D	Point 7

23. - E5D13

How much power is consumed in a circuit consisting of a 100 ohm resistor in series with a 100 ohm inductive reactance drawing 1 ampere?

Select	Answer
A	70.7 Watts
B	141.4 Watts
C	100 Watts
D	200 Watts

24. - E6A07

Which of the following indicates that a silicon NPN junction transistor is biased on?

Select	Answer
A	Base-to-emitter voltage of approximately 6 to 7 volts
B	Base-to-emitter resistance of approximately 0.6 to 0.7 ohms
C	Base-to-emitter voltage of approximately 0.6 to 0.7 volts
D	Base-to-emitter resistance of approximately 6 to 7 ohms

25. - E6B13

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

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

26. - E6C02

What happens when the level of a comparator's input signal crosses the threshold?

Select	Answer
A	The comparator changes its output state
B	The feedback loop becomes unstable
C	The IC input can be damaged
D	The comparator enters latch-up

27. - E6D02

What is the equivalent circuit of a quartz crystal?

Select	Answer
A	Motional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitor representing electrode and stray capacitance
B	Motional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance
C	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel
D	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in series

28. - E6E02

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

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

29. - E6F03

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

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

30. - E7A12

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

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

31. - E7B11

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

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

32. - E7C05

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

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

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

34. - E7E02

What is the function of a reactance modulator?

Select	Answer
A	To produce AM signals by using an electrically variable resistance
B	To produce PM signals by using an electrically variable resistance
C	To produce AM signals by using an electrically variable inductance or capacitance
D	To produce PM signals by using an electrically variable inductance or capacitance

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	Sample clock phase noise
C	Missing codes and jitter
D	Data storage transfer rate

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	0.21
B	24
C	94
D	47

37. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

Select	Answer
A	A hybrid synthesizer
B	A phase locked loop synthesizer
C	A diode-switching matrix synthesizer
D	A direct digital synthesizer

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. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

Select	Answer
A	3
B	0.3
C	1000
D	3000

40. - E8C05

What is the necessary bandwidth of a 13-WPM international Morse code transmission?

Select	Answer
A	Approximately 104 Hz
B	Approximately 13 Hz
C	Approximately 52 Hz
D	Approximately 26 Hz

41. - E8D09

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

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

42. - E9A06

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

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

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

44. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?

Select	Answer
A	The low-angle radiation increases
B	The high-angle radiation increases
C	The low-angle radiation decreases
D	Both the high-angle and low-angle radiation decrease

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Improved radiation efficiency
B	Higher losses
C	Lower Q
D	Greater structural strength

46. - E9E05

How must the driven element in a 3-element Yagi be tuned to use a hairpin matching system?

Select	Answer
A	The driven element radiation resistance must be higher than the characteristic impedance of the transmission line
B	The driven element reactance must be capacitive
C	The driven element reactance must be inductive
D	The driven element resonance must be lower than the operating frequency

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 lower loss per unit of length
C	Foam dielectric has lower safe operating voltage limits
D	Foam dielectric has higher velocity factor

48. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning prime center with regard to the reactance axis
B	Reassigning resistance values with regard to the reactance axis
C	Reassigning reactance values with regard to the resistance axis
D	Reassigning impedance values with regard to the prime center

49. - E9H10

How can the output voltage of a multiple turn receiving loop antenna be increased?

Select	Answer
A	By increasing either the number of wire turns in the loop or the area of the loop structure or both
B	By winding adjacent turns in opposing directions
C	By increasing the number of wire turns in the loop and reducing the area of the loop structure
D	By reducing the permeability of the loop shield

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Zinc oxide
B	Uranium Hexafluoride
C	Beryllium Oxide
D	Mica

Figure E5-2

Figure E7-1

Figure E7-4