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

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1. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

Select	Answer
A	On any frequency where the signal's sidebands are within the channel
B	At the highest frequency of the channel
C	At the center frequency of the channel
D	At the lowest frequency of the channel

2. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historical Places?

Select	Answer
A	An Environmental Assessment must be submitted to the FCC
B	A letter of intent must be filed with the National Audubon Society
C	A proposal must be submitted to the National Park Service
D	A form FSD-15 must be submitted to the Department of the Interior

3. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

Select	Answer
A	CEPT agreement
B	All of these choices are correct
C	ITU reciprocal license
D	IARP agreement

4. - E1D09

Which UHF amateur service bands have frequencies available for a space station?

Select	Answer
A	33 cm and 13 cm
B	70 cm only
C	70 cm and 13 cm
D	70 cm and 33 cm

5. - E1E02

Where are the questions for all written U.S. amateur license examinations listed?

Select	Answer
A	In FCC Part 97
B	In a question pool maintained by all the VECs
C	In a question pool maintained by the FCC
D	In the appropriate FCC Report and Order

6. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

Select	Answer
A	440 MHz - 450 MHz
B	222 MHz - 223 MHz
C	53 MHz - 54 MHz
D	420 MHz - 430 MHz

7. - E2A02

What is the direction of a descending pass for an amateur satellite?

Select	Answer
A	From west to east
B	From east to west
C	From south to north
D	From north to south

8. - E2B17

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

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

9. - E2C07

What is the Cabrillo format?

Select	Answer
A	A standard for submission of electronic contest logs
B	A method of exchanging information during a contest QSO
C	The most common set of contest rules
D	The rules of order for meetings between contest sponsors

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. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

Select	Answer
A	PSK31
B	PACTOR
C	RTTY
D	MT63

12. - E3A06

Which of the following is required for microwave propagation via rain scatter?

Select	Answer
A	All of these choices are correct
B	Rain droplets must be electrically charged
C	Rain droplets must be within the E layer
D	The rain must be within radio range of both stations

13. - E3B03

What is the best time of day for transequatorial propagation?

Select	Answer
A	Noon
B	Morning
C	Afternoon or early evening
D	Late at night

14. - E3C15

What might a sudden rise in radio background noise indicate?

Select	Answer
A	A meteor ping
B	Increased transequatorial propagation likely
C	A solar flare has occurred
D	Long-path propagation is occurring

15. - E4A02

Which of the following parameters would a spectrum analyzer display on the vertical and horizontal axes?

Select	Answer
A	RF amplitude and time
B	SWR and time
C	SWR and frequency
D	RF amplitude and frequency

16. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

Select	Answer
A	Input attenuator accuracy
B	Time base accuracy
C	Temperature coefficient of the logic
D	Decade divider accuracy

17. - E4C15

What is usually the primary source of noise that is heard from an HF receiver with an antenna connected?

Select	Answer
A	Induction motor noise
B	Atmospheric noise
C	Detector noise
D	Receiver front-end noise

18. - E4D09

What is the purpose of the preselector in a communications receiver?

Select	Answer
A	To increase rejection of unwanted signals
B	To provide a range of AGC time constants
C	To allow selection of the optimum RF amplifier device
D	To store often-used frequencies

19. - E4E16

What current flows equally on all conductors of an unshielded multi-conductor cable?

Select	Answer
A	Reactive current only
B	Return current
C	Common-mode current
D	Differential-mode current

20. - E5A02

What is resonance in an electrical circuit?

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

21. - E5B05

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

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

22. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By X and R values
B	By real and imaginary parts
C	By Y and G values
D	By phase angle and amplitude

23. - E5D03

What is microstrip?

Select	Answer
A	Short lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
B	Lightweight transmission line made of common zip cord
C	Precision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies
D	Miniature coax used for low power applications

24. - E6A13

What do the initials CMOS stand for?

Select	Answer
A	Common Mode Organic Silicon
B	Common Mode Oscillating System
C	Complementary Metal-Oxide Semiconductor
D	Complementary Mica-Oxide Silicon

25. - E6B01

What is the most useful characteristic of a Zener diode?

Select	Answer
A	A constant current drop under conditions of varying voltage
B	A negative resistance region
C	An internal capacitance that varies with the applied voltage
D	A constant voltage drop under conditions of varying current

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

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

27. - E6D16

What is the common name for a capacitor connected across a transformer secondary that is used to absorb transient voltage spikes?

Select	Answer
A	Feedback capacitor
B	Snubber capacitor
C	Trimmer capacitor
D	Clipper capacitor

28. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

Select	Answer
A	Nearly infinite gain, very high input impedance, and very low output impedance
B	The ability to retrieve information from a single signal even in the presence of other strong signals
C	Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range
D	Plate current that is controlled by a control grid

29. - E6F02

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

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

30. - E7A02

What is the function of a decade counter digital IC?

Select	Answer
A	It produces ten output pulses for every input pulse
B	It adds two decimal numbers together
C	It decodes a decimal number for display on a seven segment LED display
D	It produces one output pulse for every ten input pulses

31. - E7B01

For what portion of a signal cycle does a Class AB amplifier operate?

Select	Answer
A	More than 180 degrees but less than 360 degrees
B	The entire cycle
C	Less than 180 degrees
D	Exactly 180 degrees

32. - E7C07

What kind of filter would you use to attenuate an interfering carrier signal while receiving an SSB transmission?

Select	Answer
A	A band-pass filter
B	An all-pass filter
C	A notch filter
D	A Pi-network filter

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

Select	Answer
A	Input voltage multiplied by input current
B	Voltage difference from input to output multiplied by output current
C	Output voltage multiplied by output current
D	Input voltage divided by output current

34. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	A pre-emphasis network
B	A heterodyne suppressor
C	A de-emphasis network
D	An audio prescaler

35. - E7F15

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters delay all frequency components of the signal by the same amount
B	FIR filters are easier to implement for a given set of passband rolloff requirements
C	FIR filters can respond faster to impulses
D	All of these choices are correct

36. - E7G06

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

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

37. - E7H10

What information is contained in the lookup table of a direct digital frequency synthesizer?

Select	Answer
A	The phase relationship between a reference oscillator and the output waveform
B	The amplitude values that represent a sine-wave output
C	The synthesizer frequency limits and frequency values stored in the radio memories
D	The phase relationship between a voltage-controlled oscillator and the output waveform

38. - E8A09

How many levels can an analog-to-digital converter with 8 bit resolution encode?

Select	Answer
A	8
B	256 divided by the gain of the input amplifier
C	8 multiplied by the gain of the input amplifier
D	256

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
B	A digital mode for narrow band, slow speed transmissions
C	A bandwidth compression technique using Fourier transforms
D	A frequency modulation technique which uses non-harmonically related frequencies

40. - E8C04

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

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

41. - E8D05

What is the most common method of reducing key clicks?

Select	Answer
A	Low-pass filters at the transmitter output
B	Increase keying waveform rise and fall times
C	Reduce keying waveform rise and fall times
D	High-pass filters at the transmitter output

42. - E9A12

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 6 dB gain over an isotropic antenna?

Select	Answer
A	2.79 dB
B	8.15 dB
C	6.0 dB
D	3.85 dB

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

44. - E9C06

What is the effect of a terminating resistor on a rhombic antenna?

Select	Answer
A	It reflects the standing waves on the antenna elements back to the transmitter
B	It changes the radiation pattern from horizontal to vertical polarization
C	It decreases the ground loss
D	It changes the radiation pattern from bidirectional to unidirectional

45. - E9D12

Which of the following would provide the best RF ground for your station?

Select	Answer
A	An electrically short connection to a metal water pipe
B	A 50 ohm resistor connected to ground
C	An electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
D	An electrically short connection to 3 or 4 interconnected ground rods via a series RF choke

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 gamma match
B	The delta match
C	The stub match
D	The epsilon match

47. - E9F13

What impedance does a 1/4 wavelength transmission line present to a generator when the line is shorted at the far end?

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

48. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The reactance axis
B	The resistance axis
C	The voltage axis
D	The current axis

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 increasing the number of wire turns in the loop and reducing the area of the loop structure
C	By reducing the permeability of the loop shield
D	By winding adjacent turns in opposing directions

50. - E0A01

What is the primary function of an external earth connection or ground rod?

Select	Answer
A	Reduce RF current flow between pieces of equipment
B	Reduce RFI to telephones and home entertainment systems
C	Reduce received noise
D	Lightning protection

Figure E9-3