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

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1. - E1A13

Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?

Select	Answer
A	Any person named in an amateur station license grant or a person holding an unrestricted Radiotelephone Operator Permit
B	Only a person named in an amateur station license grant
C	Any person holding an FCC issued amateur license or who is authorized for alien reciprocal operation
D	Only a person with an FCC Marine Radio

2. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

Select	Answer
A	No special rules apply if your antenna structure will be less than 300 feet in height
B	You must obtain a construction permit from the airport zoning authority
C	You may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules
D	You must file an Environmental Impact Statement with the EPA before construction begins

3. - E1C13

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

Select	Answer
A	You must append "/CEPT" to your call sign
B	The U.S. embassy must approve of your operation
C	You must identify in the official language of the country in which you are operating
D	You must bring a copy of FCC Public Notice DA 11-221

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 and 13 cm
C	70 cm only
D	70 cm and 33 cm

5. - E1E10

What must the administering VEs do after the administration of a successful examination for an amateur operator license?

Select	Answer
A	They must collect and submit the documents to the coordinating VEC for grading
B	They must collect and send the documents to the FCC according to instructions
C	They must collect and send the documents to the NCVEC for grading
D	They must submit the application document to the coordinating VEC according to the coordinating VEC instructions

6. - E1F11

Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

Select	Answer
A	It must be capable of external RF switching between its input and output networks
B	It must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power
C	It must exhibit a gain of 0 dB or less over its full output range
D	It must produce full legal output when driven by not more than 5 watts of mean RF input power

7. - E2A13

What type of satellite appears to stay in one position in the sky?

Select	Answer
A	Geomagnetic
B	LEO
C	Geostationary
D	HEO

8. - E2B12

How are analog SSTV images typically transmitted on the HF bands?

Select	Answer
A	Varying tone frequencies representing the video are transmitted using PSK
B	Video is converted to equivalent Baudot representation
C	Video is converted to equivalent ASCII representation
D	Varying tone frequencies representing the video are transmitted using single sideband

9. - E2C03

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

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

10. - E2D08

What type of packet frame is used to transmit APRS beacon data?

Select	Answer
A	Connect
B	Acknowledgement
C	Disconnect
D	Unnumbered Information

11. - E2E13

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

Select	Answer
A	All of these choices are correct
B	Your transmit frequency is incorrect
C	The protocol version you are using is not the supported by the digital station
D	Another station you are unable to hear is using the frequency

12. - E3A02

What characterizes libration fading of an EME signal?

Select	Answer
A	A fluttery irregular fading
B	A slow change in the pitch of the CW signal
C	A gradual loss of signal as the Sun rises
D	The returning echo is several Hertz lower in frequency than the transmitted signal

13. - E3B08

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

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

14. - E3C04

What does the value of Bz (B sub Z) represent?

Select	Answer
A	Direction and strength of the interplanetary magnetic field
B	Critical frequency for vertical transmissions
C	Duration of long-delayed echoes
D	Geomagnetic field stability

15. - E4A15

What is an advantage of a period-measuring frequency counter over a direct-count type?

Select	Answer
A	It can run on battery power for remote measurements
B	It provides improved resolution of low-frequency signals within a comparable time period
C	It can directly measure the modulation index of an FM transmitter
D	It does not require an expensive high-precision time base

16. - E4B07

What do the subscripts of S parameters represent?

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

17. - E4C04

How is the noise figure of a receiver defined?

Select	Answer
A	The ratio of atmospheric noise to phase noise
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 the noise bandwidth in Hertz to the theoretical bandwidth of a resistive network

18. - E4D09

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

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

19. - E4E06

What is a major cause of atmospheric static?

Select	Answer
A	Thunderstorms
B	Meteor showers
C	Geomagnetic storms
D	Solar radio frequency emissions

20. - E5A03

What is the magnitude of the impedance of a series RLC circuit at resonance?

Select	Answer
A	Approximately equal to circuit resistance
B	Approximately equal to inductive reactance
C	High, as compared to the circuit resistance
D	Approximately equal to capacitive reactance

21. - E5B13

What letter is commonly used to represent susceptance?

Select	Answer
A	Y
B	B
C	G
D	X

22. - E5C01

Which of the following represents a capacitive reactance in rectangular notation?

Select	Answer
A	-jX
B	+jX
C	Omega
D	X

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. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

Select	Answer
A	Donor impurity
B	Acceptor impurity
C	Insulator impurity
D	N-type impurity

25. - E6B12

What is one common use for PIN diodes?

Select	Answer
A	As an RF switch
B	As a constant current source
C	As a constant voltage source
D	As a high voltage rectifier

26. - E6C12

What is BiCMOS logic?

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

27. - E6D12

What is the definition of saturation in a ferrite core inductor?

Select	Answer
A	Adjacent inductors become over-coupled
B	The inductor windings are over coupled
C	The inductor's voltage rating is exceeded causing a flashover
D	The ability of the inductor's core to store magnetic energy has been exceeded

28. - E6E10

What is the packaging technique in which leadless components are soldered directly to circuit boards?

Select	Answer
A	Virtual lead mounting
B	Surface mount
C	Direct soldering
D	Stripped lead

29. - E6F04

What is the photovoltaic effect?

Select	Answer
A	The conversion of voltage to current when exposed to light
B	The conversion of electrical energy to mechanical energy
C	The conversion of light to electrical energy
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	2
B	8
C	4
D	1

31. - E7B01

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

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

32. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

Select	Answer
A	It is a notch filter
B	It is a low-pass filter
C	It is a high-pass filter
D	It is a band-pass filter

33. - E7D16

When several electrolytic filter capacitors are connected in series to increase the operating voltage of a power supply filter circuit, why should resistors be connected across each capacitor?

Select	Answer
A	To provide a safety bleeder to discharge the capacitors when the supply is off
B	To provide a minimum load current to reduce voltage excursions at light loads
C	All of these choices are correct
D	To equalize, as much as possible, the voltage drop across each capacitor

34. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

Select	Answer
A	The sum, difference and square root of the input frequencies
B	1.414 and 0.707 times the input frequency
C	Two and four times the original frequency
D	The two input frequencies along with their sum and difference frequencies

35. - E7F07

What function can a Fast Fourier Transform perform?

Select	Answer
A	Converting digital signals to analog form
B	Converting 8-bit data to 16 bit data
C	Converting analog signals to digital form
D	Converting digital signals from the time domain to the frequency domain

36. - E7G04

What is meant by the term op-amp input offset voltage?

Select	Answer
A	The differential input voltage needed to bring the open loop output voltage to zero
B	The output voltage of the op-amp minus its input voltage
C	The potential between the amplifier input terminals of the op-amp in an open loop condition
D	The difference between the output voltage of the op-amp and the input voltage required in the immediately following stage

37. - E7H07

How can an oscillator's microphonic responses be reduced?

Select	Answer
A	Use of NP0 capacitors
B	Using the oscillator only for CW and digital signals
C	Eliminating noise on the oscillator's power supply
D	Mechanically isolating the oscillator circuitry from its enclosure

38. - E8A12

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

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

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	3
B	6000
C	2000
D	1/3

40. - E8C10

What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits

Select	Answer
A	It increases security
B	It has more resolution than simple binary
C	It has more possible states than simple binary
D	It facilitates error detection

41. - E8D06

Which of the following indicates likely overmodulation of an AFSK signal such as PSK or MFSK?

Select	Answer
A	High reflected power
B	Rapid signal fading
C	Strong ALC action
D	Harmonics on higher bands

42. - E9A08

What is meant by antenna bandwidth?

Select	Answer
A	The angle between the half-power radiation points
B	The frequency range over which an antenna satisfies a performance requirement
C	The angle formed between two imaginary lines drawn through the element ends
D	Antenna length divided by the number of elements

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

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	Both the high-angle and low-angle radiation decrease
C	The high-angle radiation increases
D	The low-angle radiation decreases

45. - E9D08

What happens as the Q of an antenna increases?

Select	Answer
A	SWR bandwidth decreases
B	SWR bandwidth increases
C	Gain is reduced
D	More common-mode current is present on the feed line

46. - E9E10

Which of these choices is an effective way to match an antenna with a 100 ohm feed point impedance to a 50 ohm coaxial cable feed line?

Select	Answer
A	Insert a 1/2 wavelength piece of 300 ohm twin-lead in series between the antenna terminals and the 50 ohm feed cable
B	Connect 1/2 wavelength shorted stub of 75 ohm cable in parallel with the 50 ohm cable where it attaches to the antenna
C	Insert a 1/4-wavelength piece of 75 ohm coaxial cable transmission line in series between the antenna terminals and the 50 ohm feed cable
D	Connect a 1/4-wavelength open stub of 300 ohm twin-lead in parallel with the coaxial feed line where it connects to the antenna

47. - E9F08

What is the term for the ratio of the actual speed at which a signal travels through a transmission line to the speed of light in a vacuum?

Select	Answer
A	Standing wave ratio
B	Velocity factor
C	Surge impedance
D	Characteristic impedance

48. - E9G01

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

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

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

Select	Answer
A	One or more turns of wire wound in the shape of a large open coil
B	A small coil of wire tightly wound around a toroidal ferrite core
C	A vertical antenna coupled to a feed line through an inductive loop of wire
D	A large circularly polarized antenna

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	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations
C	Only commercial transmitters
D	Only the most powerful transmitter