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

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

3. - E1C07

What is meant by local control?

Select	Answer
A	Controlling a repeater using a portable handheld transceiver
B	Direct manipulation of the transmitter by a control operator
C	Controlling a station through a local auxiliary link
D	Automatically manipulating local station controls

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

Select	Answer
A	Only those of Amateur Extra Class operators
B	Only those of General, Advanced or Amateur Extra Class operators
C	Any amateur station, subject to the privileges of the class of operator license held by the control operator
D	Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau

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	The VE session manager
D	Each administering VE

6. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

Select	Answer
A	To provide temporary operation while awaiting normal licensing
B	To allow regular operation on Land Mobile channels
C	To provide additional spectrum for personal use
D	To provide for experimental amateur communications

7. - E2A03

What is the orbital period of an Earth satellite?

Select	Answer
A	The time it takes for a satellite to complete one revolution around the Earth
B	The point of minimum height of a satellite's orbit
C	The time it takes for a satellite to travel from perigee to apogee
D	The point of maximum height of a satellite's orbit

8. - E2B15

What signals SSTV receiving equipment to begin a new picture line?

Select	Answer
A	A two-tone signal
B	Specific tone frequencies
C	Specific tone amplitudes
D	Elapsed time

9. - E2C01

Which of the following is true about contest operating?

Select	Answer
A	Every contest requires a signal report in the exchange
B	Interference to other amateurs is unavoidable and therefore acceptable
C	It is mandatory to transmit the call sign of the station being worked as part of every transmission to that station
D	Operators are permitted to make contacts even if they do not submit a log

10. - E2D07

What digital protocol is used by APRS?

Select	Answer
A	802.11
B	AX.25
C	AMTOR
D	PACTOR

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

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

12. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

Select	Answer
A	When the Moon is at apogee
B	When the Moon is full
C	When the MUF is above 30 MHz
D	When the Moon is at perigee

13. - E3B13

Why is chordal hop propagation desirable?

Select	Answer
A	The signal experiences less loss along the path compared to normal skip propagation
B	The MUF for chordal hop propagation is much lower than for normal skip propagation
C	Atmospheric noise is lower in the direction of chordal hop propagation
D	Signals travel faster along ionospheric chords

14. - E3C13

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

Select	Answer
A	Circular
B	Vertical
C	Horizontal
D	Elliptical

15. - E4A11

Which of the following is good practice when using an oscilloscope probe?

Select	Answer
A	Keep the signal ground connection of the probe as short as possible
B	All of these choices are correct
C	Never use a DC-coupled probe to measure an AC circuit
D	Never use a high impedance probe to measure a low impedance circuit

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

Select	Answer
A	Low reluctance input
B	Low impedance input
C	High reluctance input
D	High impedance input

17. - E4C05

What does a value of -174 dBm/Hz represent with regard to the noise floor of a receiver?

Select	Answer
A	The noise figure of a 1 Hz bandwidth receiver
B	The minimum detectable signal as a function of receive frequency
C	The galactic noise contribution to minimum detectable signal
D	The theoretical noise at the input of a perfect receiver at room temperature

18. - E4D08

What causes intermodulation in an electronic circuit?

Select	Answer
A	Positive feedback
B	Too little gain
C	Nonlinear circuits or devices
D	Lack of neutralization

19. - E4E04

How can conducted and radiated noise caused by an automobile alternator be suppressed?

Select	Answer
A	By installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead
B	By installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead
C	By connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads
D	By installing a noise suppression resistor and a blocking capacitor in both leads

20. - E5A17

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

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

21. - E5B02

What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

Select	Answer
A	One discharge period
B	One time constant
C	A discharge factor of one
D	An exponential discharge rate of one

22. - E5C01

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

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

23. - E5D03

What is microstrip?

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

24. - E6A09

What is a depletion-mode FET?

Select	Answer
A	Any FET without a channel
B	An FET that has no current flow between source and drain when no gate voltage is applied
C	Any FET for which holes are the majority carriers
D	An FET that exhibits a current flow between source and drain when no gate voltage is applied

25. - E6B01

What is the most useful characteristic of a Zener diode?

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

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	All of these choices are correct
C	It has the high input impedance of CMOS and the low output impedance of bipolar transistors
D	It is totally immune to electrostatic damage

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. - E6E12

Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?

Select	Answer
A	To provide a low-pass frequency response
B	Enhanced sensitivity to light
C	Better dissipation of heat
D	High-voltage insulating ability

29. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

Select	Answer
A	Silicon
B	Selenium
C	Copper oxide
D	Cadmium Sulfide

30. - E7A10

What is a truth table?

Select	Answer
A	A table of logic symbols that indicate the logic states of an op-amp
B	A list of inputs and corresponding outputs for a digital device
C	A diagram showing logic states when the digital device output is true
D	A table of logic symbols that indicate the high logic states of an op-amp

31. - E7B18

What is a characteristic of a grounded-grid amplifier?

Select	Answer
A	High power gain
B	Low input impedance
C	High filament voltage
D	Low bandwidth

32. - E7C06

What are the distinguishing features of an elliptical filter?

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

33. - E7D10

What is the primary reason that a high-frequency switching type high voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

Select	Answer
A	The high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
B	The inverter design does not require any output filtering
C	It uses a diode bridge rectifier for increased output
D	It uses a large power factor compensation capacitor to create free power from the unused portion of the AC cycle

34. - E7E02

What is the function of a reactance modulator?

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

35. - E7F08

What is the function of decimation with regard to digital filters?

Select	Answer
A	Attenuating the signal
B	Reducing the effective sample rate by removing samples
C	Removing unnecessary significant digits
D	Converting data to binary code decimal form

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	94
B	0.21
C	24
D	47

37. - E7H04

How is positive feedback supplied in a Colpitts oscillator?

Select	Answer
A	Through a capacitive divider
B	Through a neutralizing capacitor
C	Through link coupling
D	Through a tapped coil

38. - E8A10

What is the purpose of a low pass filter used in conjunction with a digital-to-analog converter?

Select	Answer
A	Lower the input bandwidth to increase the effective resolution
B	Remove harmonics from the output caused by the discrete analog levels generated
C	All of these choices are correct
D	Improve accuracy by removing out of sequence codes from the input

39. - E8B11

What is digital time division multiplexing?

Select	Answer
A	Two or more data streams are assigned to discrete sub-carriers on an FM transmitter
B	Two or more signals are quadrature modulated to increase bandwidth efficiency
C	Two or more signals are arranged to share discrete time slots of a data transmission
D	Two or more data streams share the same channel by transmitting time of transmission as the sub-carrier

40. - E8C07

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

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

41. - E8D01

Why are received spread spectrum signals resistant to interference?

Select	Answer
A	Signals not using the spread spectrum algorithm are suppressed in the receiver
B	The high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
C	The receiver is always equipped with a digital blanker
D	If interference is detected by the receiver it will signal the transmitter to change frequencies

42. - E9A13

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 12 dB gain over an isotropic antenna?

Select	Answer
A	9.85 dB
B	14.15 dB
C	12.5 dB
D	6.17 dB

43. - E9B10

What is the principle of a Method of Moments analysis?

Select	Answer
A	A wire is modeled as a series of points, each having a distinct location in space
B	A wire is modeled as a series of segments, each having a uniform value of current
C	A wire is modeled as a series of segments, each having a distinct value of voltage across it
D	A wire is modeled as a single sine-wave current generator

44. - E9C10

Which of the following describes a Zepp antenna?

Select	Answer
A	An end fed dipole antenna
B	A dipole constructed from zip cord
C	An omni-directional antenna commonly used for satellite communications
D	A vertical array capable of quickly changing the direction of maximum radiation by changing phasing lines

45. - E9D05

What is a disadvantage of using a multiband trapped antenna?

Select	Answer
A	It radiates the harmonics and fundamental equally well
B	It must be neutralized
C	It is too sharply directional at lower frequencies
D	It might radiate harmonics

46. - E9E03

What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?

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

47. - E9F07

How does ladder line compare to small-diameter coaxial cable such as RG-58 at 50 MHz?

Select	Answer
A	Smaller reflection coefficient
B	Lower loss
C	Lower velocity factor
D	Higher SWR

48. - E9G05

What type of chart is shown in Figure E9-3?

Select	Answer
A	Smith chart
B	Elevation angle radiation pattern chart
C	Azimuth angle radiation pattern chart
D	Free space radiation directivity chart

49. - E9H08

What is the function of a sense antenna?

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

50. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Advise your neighbors of the results of your tests
B	Make sure signals from your station are less than the uncontrolled MPE limits
C	Make sure signals from your station are less than the controlled MPE limits
D	You need only evaluate exposure levels on your own property

Figure E7-4

Figure E9-3