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

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1. - E1A07

Which amateur band requires transmission on specific channels rather than on a range of frequencies?

Select	Answer
A	17 meter band
B	12 meter band
C	60 meter band
D	30 meter band

2. - E1B09

Which amateur stations may be operated under RACES rules?

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

3. - E1C04

What is meant by IARP?

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

4. - E1D06

Which of the following is a requirement of a space station?

Select	Answer
A	The space station must be capable of changing its orbit whenever such a change is ordered by NASA
B	All of these choices are correct
C	The space station must be capable of terminating transmissions by telecommand when directed by the FCC
D	The space station must cease all transmissions after 5 years

5. - E1E05

What is the minimum passing score on amateur operator license examinations?

Select	Answer
A	Minimum passing score of 80%
B	Minimum passing score of 70%
C	Minimum passing score of 77%
D	Minimum passing score of 74%

6. - E1F07

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

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

7. - E2A05

What do the letters in a satellite's mode designator specify?

Select	Answer
A	The location of the ground control station
B	The polarization of uplink and downlink signals
C	The uplink and downlink frequency ranges
D	Power limits for uplink and downlink transmissions

8. - E2B03

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

Select	Answer
A	By scanning each field from bottom to top
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 lines from left to right in one field and right to left in the next

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

Select	Answer
A	An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
B	A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
C	The acceptable practice of manually posting the call signs of stations on a spotting network
D	The generally prohibited practice of posting one's own call sign and frequency on a spotting network

10. - E2D06

Which of the following describes a method of establishing EME contacts?

Select	Answer
A	Judging optimum transmission times by monitoring beacons reflected from the Moon
B	Time synchronous transmissions alternately from each station
C	Storing and forwarding digital messages
D	High speed CW identification to avoid fading

11. - E2E03

How is the timing of JT65 contacts organized?

Select	Answer
A	By exchanging ACK/NAK packets
B	It depends on the lunar phase
C	Stations take turns on alternate days
D	Alternating transmissions at 1 minute intervals

12. - E3A11

What is a typical range for tropospheric propagation of microwave signals?

Select	Answer
A	100 miles to 300 miles
B	10 miles to 50 miles
C	2500 miles
D	1200 miles

13. - E3B08

What type of HF propagation is probably occurring if radio signals travel along the terminator between daylight and darkness?

Select	Answer
A	Transequatorial
B	Long-path
C	Sporadic-E
D	Gray-line

14. - E3C13

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

Select	Answer
A	Horizontal
B	Vertical
C	Elliptical
D	Circular

15. - E4A14

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

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

16. - E4B11

How should an antenna analyzer be connected when measuring antenna resonance and feed point impedance?

Select	Answer
A	Connect the analyzer via a high-impedance transformer to the antenna
B	Loosely couple the analyzer near the antenna base
C	Loosely couple the antenna and a dummy load to the analyzer
D	Connect the antenna feed line directly to the analyzer's connector

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	Overload
C	Excess output level
D	Loss of sensitivity

18. - E4D14

Which of the following is a way to reduce the likelihood of receiver desensitization?

Select	Answer
A	Switch from fast AGC to slow AGC
B	Raise the receiver IF frequency
C	Increase the receiver front end gain
D	Decrease the RF bandwidth of the receiver

19. - E4E10

What is a common characteristic of interference caused by a touch controlled electrical device?

Select	Answer
A	All of these choices are correct
B	The interfering signal may drift slowly across the HF spectrum
C	The interfering signal can be several kHz in width and usually repeats at regular intervals across a HF band
D	The interfering signal sounds like AC hum on an AM receiver or a carrier modulated by 60 Hz hum on a SSB or CW receiver

20. - E5A11

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

Select	Answer
A	315.6 Hz
B	157.8 Hz
C	23.67 kHz
D	47.3 kHz

21. - E5B10

What is the relationship between the current through an inductor and the voltage across an inductor?

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

22. - E5C07

What is a vector?

Select	Answer
A	The inverse of the sine function
B	A quantity with both magnitude and an angular component
C	The value of a quantity that changes over time
D	The inverse of the tangent function

23. - E5D16

What is the power factor of an R-L circuit having a 30 degree phase angle between the voltage and the current?

Select	Answer
A	0.866
B	1.73
C	0.577
D	0.5

24. - E6A13

What do the initials CMOS stand for?

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

25. - E6B11

What is used to control the attenuation of RF signals by a PIN diode?

Select	Answer
A	Capacitance of an RF coupling capacitor
B	Reverse voltage larger than the RF signal
C	A sub-harmonic pump signal
D	Forward DC bias current

26. - E6C12

What is BiCMOS logic?

Select	Answer
A	A FET logic family based on bimetallic semiconductors
B	A logic device with two CMOS circuits per package
C	A logic family based on bismuth CMOS devices
D	An integrated circuit logic family using both bipolar and CMOS transistors

27. - E6D01

How many turns will be required to produce a 5-microhenry inductor using a powdered-iron toroidal core that has an inductance index (A L) value of 40 microhenrys/100 turns?

Select	Answer
A	141 turns
B	13 turns
C	35 turns
D	79 turns

28. - E6E05

Which of the following noise figure values is typical of a low-noise UHF preamplifier?

Select	Answer
A	2 dB
B	44 dBm
C	-10 dB
D	-20 dBm

29. - E6F04

What is the photovoltaic effect?

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

30. - E7A02

What is the function of a decade counter digital IC?

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

31. - E7B17

Why are odd-order rather than even-order intermodulation distortion products of concern in linear power amplifiers?

Select	Answer
A	Because they invert the sidebands causing distortion
B	Because they are relatively far in frequency from the desired signal
C	Because they are relatively close in frequency to the desired signal
D	Because they maintain the sidebands, thus causing multiple duplicate signals

32. - E7C06

What are the distinguishing features of an elliptical filter?

Select	Answer
A	Gradual passband rolloff with minimal stop band ripple
B	Gradual passband rolloff with extreme stop band ripple
C	Extremely sharp cutoff with one or more notches in the stop band
D	Extremely flat response over its pass band with gradually rounded stop band corners

33. - E7D11

What circuit element is controlled by a series analog voltage regulator to maintain a constant output voltage?

Select	Answer
A	Reference voltage
B	Error amplifier
C	Pass transistor
D	Switching inductance

34. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

Select	Answer
A	Spurious mixer products are generated
B	A beat frequency is generated
C	Automatic limiting occurs
D	Mixer blanking occurs

35. - E7F11

What sets the minimum detectable signal level for an SDR in the absence of atmospheric or thermal noise?

Select	Answer
A	Data storage transfer rate
B	Missing codes and jitter
C	Reference voltage level and sample width in bits
D	Sample clock phase noise

36. - E7G01

What is the typical output impedance of an integrated circuit op-amp?

Select	Answer
A	Very low
B	1000 ohms
C	100 ohms
D	Very high

37. - E7H11

What are the major spectral impurity components of direct digital synthesizers?

Select	Answer
A	Spurious signals at discrete frequencies
B	Nyquist limit noise
C	Broadband noise
D	Digital conversion noise

38. - E8A12

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

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

39. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

Select	Answer
A	6000
B	3
C	1/3
D	2000

40. - E8C05

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

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

41. - E8D02

What spread spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?

Select	Answer
A	Frequency hopping
B	Phase compandored spread spectrum
C	Direct sequence
D	Binary phase-shift keying

42. - E9A10

Which of the following choices is a way to improve the efficiency of a ground-mounted quarter-wave vertical antenna?

Select	Answer
A	Install a good radial system
B	Shorten the radiating element
C	Reduce the diameter of the radiating element
D	Isolate the coax shield from ground

43. - E9B16

How many elevation lobes appear in the forward direction of the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	7
B	1
C	4
D	3

44. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

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

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

46. - E9E07

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

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

47. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

Select	Answer
A	The characteristic impedance is higher in a parallel feed line
B	Skin effect is less pronounced in the coaxial cable
C	Electrical signals move more slowly in a coaxial cable than in air
D	The surge impedance is higher in a parallel feed line

48. - E9G11

How are the wavelength scales on a Smith chart calibrated?

Select	Answer
A	In fractions of transmission line electrical wavelength
B	In fractions of antenna electrical wavelength
C	In fractions of transmission line electrical frequency
D	In fractions of antenna electrical frequency

49. - E9H02

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

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

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	Beryllium Oxide
B	Zinc oxide
C	Uranium Hexafluoride
D	Mica

Figure E9-2