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

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1. - E1A08

If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

Select	Answer
A	The control operator of the packet bulletin board station
B	The control operators of all the stations in the system
C	The control operators of all the stations in the system not authenticating the source from which they accept communications
D	The control operator of the originating station

2. - E1B09

Which amateur stations may be operated under RACES rules?

Select	Answer
A	Only those club stations licensed to Amateur Extra class operators
B	Any FCC-licensed amateur station certified by the responsible civil defense organization for the area served
C	Any FCC-licensed amateur station except a Technician class
D	Any FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)

3. - E1C09

Which of these ranges of frequencies is available for an automatically controlled repeater operating below 30 MHz?

Select	Answer
A	10.100 MHz - 10.150 MHz
B	29.500 MHz - 29.700 MHz
C	24.940 MHz - 24.990 MHz
D	18.110 MHz - 18.168 MHz

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 be capable of changing its orbit whenever such a change is ordered by NASA
C	The space station must cease all transmissions after 5 years
D	All of these choices are correct

5. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

Select	Answer
A	Return the application document to the examinee
B	Send the application form to the FCC and inform the FCC of the grade
C	Destroy the application form
D	Maintain the application form with the VEC's records

6. - E1F02

What privileges are authorized in the U.S. to persons holding an amateur service license granted by the Government of Canada?

Select	Answer
A	All privileges of the Extra Class license
B	Full privileges, up to and including those of the Extra Class License, on the 80, 40, 20, 15, and 10 meter bands
C	The operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Extra Class privileges
D	None, they must obtain a U.S. license

7. - E2A04

What is meant by the term mode as applied to an amateur radio satellite?

Select	Answer
A	The type of signals that can be relayed through the satellite
B	The satellite's uplink and downlink frequency bands
C	Whether the satellite is in a polar or equatorial orbit
D	The satellite's orientation with respect to the Earth

8. - E2B03

How is an interlaced scanning pattern generated in a fast-scan (NTSC) television system?

Select	Answer
A	By scanning lines from left to right in one field and right to left in the next
B	By scanning odd numbered lines in one field and even numbered lines in the next
C	By scanning two fields simultaneously
D	By scanning each field from bottom to top

9. - E2C03

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

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

10. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
B	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
C	An APRS station with a GPS unit can automatically transmit information to show a mobile station's position during the event
D	All of these choices are correct

11. - E2E07

What is the typical bandwidth of a properly modulated MFSK16 signal?

Select	Answer
A	31 Hz
B	2.16 kHz
C	316 Hz
D	550 Hz

12. - E3A16

Which of the following best describes electromagnetic waves traveling in free space?

Select	Answer
A	Changing electric and magnetic fields propagate the energy
B	The waves are reflected by the ionosphere and return to their source
C	Electric and magnetic fields become aligned as they travel
D	The energy propagates through a medium with a high refractive index

13. - E3B11

At what time of day is Sporadic-E propagation most likely to occur?

Select	Answer
A	Any time
B	Around sunrise
C	Early evening
D	Around sunset

14. - E3C01

What does the term ray tracing describe in regard to radio communications?

Select	Answer
A	Evaluating high voltage sources for X-Rays
B	Modeling a radio wave's path through the ionosphere
C	The process in which an electronic display presents a pattern
D	Determining the radiation pattern from an array of antennas

15. - E4A12

Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?

Select	Answer
A	All of these choices are correct
B	Use high quality double shielded coaxial cables to reduce signal losses
C	Match the antenna to the load
D	Attenuate the transmitter output going to the spectrum analyzer

16. - E4B05

If a frequency counter with a specified accuracy of +/- 10 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	1465.20 Hz
B	146.52 Hz
C	146.52 kHz
D	10 Hz

17. - E4C16

Which of the following is caused by missing codes in an SDR receiver's analog-to-digital converter?

Select	Answer
A	Distortion
B	Excess output level
C	Overload
D	Loss of sensitivity

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

19. - E4E03

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

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

20. - E5A17

What is the result of increasing the Q of an impedance-matching circuit?

Select	Answer
A	Matching bandwidth is decreased
B	Matching bandwidth is increased
C	Matching range is increased
D	It has no effect on impedance matching

21. - E5B08

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?

Select	Answer
A	76 degrees with the voltage leading the current
B	14 degrees with the voltage leading the current
C	14 degrees with the voltage lagging the current
D	76 degrees with the voltage lagging the current

22. - E5C04

Which of the following represents a capacitive reactance in polar coordinates?

Select	Answer
A	A positive real part
B	A negative real part
C	A negative phase angle
D	A positive phase angle

23. - E5D01

What is the result of skin effect?

Select	Answer
A	Thermal effects on the surface of the conductor increase the impedance
B	Thermal effects on the surface of the conductor decrease the impedance
C	As frequency decreases, RF current flows in a thinner layer of the conductor, closer to the surface
D	As frequency increases, RF current flows in a thinner layer of the conductor, closer to the surface

24. - E6A05

What is the alpha of a bipolar junction transistor?

Select	Answer
A	The change of collector current with respect to gate current
B	The change of base current with respect to collector current
C	The change of collector current with respect to emitter current
D	The change of collector current with respect to base current

25. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch or attenuator?

Select	Answer
A	Extremely high reverse breakdown voltage
B	Reverse bias controls its forward voltage drop
C	Ability to dissipate large amounts of power
D	A large region of intrinsic material

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

Select	Answer
A	It has the high input impedance of CMOS and the low output impedance of bipolar transistors
B	Its simplicity results in much less expensive devices than standard CMOS
C	All of these choices are correct
D	It is totally immune to electrostatic damage

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	Magnetizing current
C	Excitation current
D	Stabilizing current

28. - E6E01

Which of the following is true of a charge-coupled device (CCD)?

Select	Answer
A	It samples an analog signal and passes it in stages from the input to the output
B	It is used in a battery charger circuit
C	Its phase shift changes rapidly with frequency
D	It is a CMOS analog-to-digital converter

29. - E6F04

What is the photovoltaic effect?

Select	Answer
A	The conversion of light to electrical energy
B	The conversion of electrical energy to mechanical energy
C	The conversion of voltage to current when exposed to light
D	The tendency of a battery to discharge when used outside

30. - E7A04

How many flip-flops are required to divide a signal frequency by 4?

Select	Answer
A	1
B	8
C	2
D	4

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	Neutralization
C	Select transistors with high beta
D	Use a resistor in series with the emitter

32. - E7C05

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

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

33. - E7D15

What is the purpose of a "step-start" circuit in a high voltage power supply?

Select	Answer
A	To compensate for variations of the incoming line voltage
B	To provide a dual-voltage output for reduced power applications
C	To allow for remote control of the power supply
D	To allow the filter capacitors to charge gradually

34. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

Select	Answer
A	For higher efficiency
B	To reduce impulse noise reception
C	To remove third-order distortion products
D	For compatibility with transmitters using phase modulation

35. - E7F04

What is a common method of generating an SSB signal using digital signal processing?

Select	Answer
A	Mixing products are converted to voltages and subtracted by adder circuits
B	Combine signals with a quadrature phase relationship
C	A frequency synthesizer removes the unwanted sidebands
D	Emulation of quartz crystal filter characteristics

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 RF amplifier used in the UHF and microwave regions
D	A digital audio amplifier whose characteristics are determined by components external to the amplifier

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

Select	Answer
A	Pierce, Fenner and Beane
B	Taft, Pierce and negative feedback
C	Colpitts, Hartley and Pierce
D	Taft, Hartley and Pierce

38. - E8A01

What is the name of the process that shows that a square wave is made up of a sine wave plus all of its odd harmonics?

Select	Answer
A	Vector analysis
B	Differential analysis
C	Numerical analysis
D	Fourier analysis

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	1000
C	3000
D	0.3

40. - E8C07

What is the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

Select	Answer
A	4.8 kHz
B	15.36 kHz
C	9.6 kHz
D	5.76 kHz

41. - E8D09

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

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

42. - E9A04

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

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

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

Select	Answer
A	24 dB
B	15 dB
C	28 dB
D	3 dB

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

45. - E9D01

How does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

Select	Answer
A	Gain increases by 3 dB
B	Gain increases by 6 dB
C	Gain does not change
D	Gain is multiplied by 0.707

46. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

Select	Answer
A	The delta match
B	The gamma match
C	The epsilon match
D	The stub match

47. - E9F14

What impedance does a 1/2 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	Very low impedance
B	The same as the output impedance of the generator
C	Very high impedance
D	The same as the characteristic impedance of the line

48. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Impedance along transmission lines
B	Radio propagation
C	Radiation resistance
D	Antenna radiation pattern

49. - E9H08

What is the function of a sense antenna?

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

50. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

Select	Answer
A	All of these choices are correct
B	Ground reflections and scattering make the field impedance vary with location
C	E field and H field radiation intensity peaks can occur at different locations
D	The body reacts to electromagnetic radiation from both the E and H fields

Figure E9-2