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

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1. - E1A10

If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?

Select	Answer
A	The amateur operator must have an FCC Marine or Aircraft endorsement on his or her amateur license
B	The amateur station must have a power supply that is completely independent of the main ship or aircraft power supply
C	Its operation must be approved by the master of the ship or the pilot in command of the aircraft
D	The amateur station operator must agree not to transmit when the main radio of the ship or aircraft is in use

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

3. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

Select	Answer
A	Under automatic control there is no control operator
B	Under automatic control the control operator is not required to be present at the control point
C	Under local control there is no control operator
D	Under local control a control operator is not required to be present at a control point

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

Select	Answer
A	2 meters
B	6 meters, 2 meters, and 1.25 meters
C	6 meters and 2 meters
D	2 meters and 1.25 meters

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

6. - E1F08

Which of the following types of amateur station communications are prohibited?

Select	Answer
A	Communications in a language other than English
B	Communications that have a political content, except as allowed by the Fairness Doctrine
C	Communications transmitted for hire or material compensation, except as otherwise provided in the rules
D	Communications that have a religious content

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

Select	Answer
A	Bandwidth compressed LORAN
B	Radar
C	APRS
D	Doppler shift of beacon signals

8. - E2B10

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

Select	Answer
A	10 KHz
B	20 KHz
C	3 KHz
D	15 KHz

9. - E2C13

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control where the transmitter is located in the U.S.?

Select	Answer
A	/R# where # is the district of the remote station
B	No additional indicator is required
C	/ followed by the USPS two letter abbreviation for the state in which the remote station is located
D	The ARRL section of the remote station

10. - E2D08

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

Select	Answer
A	Unnumbered Information
B	Acknowledgement
C	Connect
D	Disconnect

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

12. - E3A08

When a meteor strikes the Earth's atmosphere, a cylindrical region of free electrons is formed at what layer of the ionosphere?

Select	Answer
A	The F2 layer
B	The F1 layer
C	The E layer
D	The D layer

13. - E3B11

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

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

14. - E3C04

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

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

15. - E4A01

Which of the following parameter determines the bandwidth of a digital or computer-based oscilloscope?

Select	Answer
A	Sample resolution
B	Input capacitance
C	Input impedance
D	Sampling rate

16. - E4B09

What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?

Select	Answer
A	There is an impedance mismatch between the antenna and feed line
B	The transmitter is not properly neutralized
C	There is more power going into the antenna
D	There is possibly a short to ground in the feed line

17. - E4C09

Which of the following choices is a good reason for selecting a high frequency for the design of the IF in a conventional HF or VHF communications receiver?

Select	Answer
A	Fewer components in the receiver
B	Easier for front-end circuitry to eliminate image responses
C	Reduced drift
D	Improved receiver noise figure

18. - E4D06

What is the term for unwanted signals generated by the mixing of two or more signals?

Select	Answer
A	Intermodulation interference
B	Amplifier desensitization
C	Neutralization
D	Adjacent channel interference

19. - E4E04

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

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

20. - E5A05

What is the magnitude of the current at the input of a series RLC circuit as the frequency goes through resonance?

Select	Answer
A	R/L
B	Minimum
C	L/R
D	Maximum

21. - E5B05

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

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

22. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

Select	Answer
A	Phasor diagram
B	Far field diagram
C	Near field diagram
D	Venn diagram

23. - E5D17

How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200VAC at 5 amperes?

Select	Answer
A	1000 watts
B	200 watts
C	1600 watts
D	600 watts

24. - E6A07

Which of the following indicates that a silicon NPN junction transistor is biased on?

Select	Answer
A	Base-to-emitter resistance of approximately 6 to 7 ohms
B	Base-to-emitter voltage of approximately 6 to 7 volts
C	Base-to-emitter resistance of approximately 0.6 to 0.7 ohms
D	Base-to-emitter voltage of approximately 0.6 to 0.7 volts

25. - E6B09

What is a common use for point contact diodes?

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

26. - E6C07

What best describes a pull-up or pull-down resistor?

Select	Answer
A	A resistor in a keying circuit used to reduce key clicks
B	A resistor connected to an op-amp output that only functions when the logic output is false
C	A resistor that insures that an oscillator frequency does not drive lower over time
D	A resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit

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	35 turns
B	79 turns
C	141 turns
D	13 turns

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	High-voltage insulating ability
C	Enhanced sensitivity to light
D	Better dissipation of heat

29. - E6F04

What is the photovoltaic effect?

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

30. - E7A07

What logical operation does a NAND gate perform?

Select	Answer
A	It produces logic "0" at its output only when all inputs are logic "1"
B	It produces logic "0" at its output only when all inputs are logic "0"
C	It produces logic "1" at its output only when all inputs are logic "1"
D	It produces logic "0" at its output if some but not all inputs are logic "1"

31. - E7B14

Why are switching amplifiers more efficient than linear amplifiers?

Select	Answer
A	The power transistor is at saturation or cut off most of the time, resulting in low power dissipation
B	Linear amplifiers have high gain resulting in higher harmonic content
C	Switching amplifiers use push-pull circuits
D	Switching amplifiers operate at higher voltages

32. - E7C15

What is a crystal lattice filter?

Select	Answer
A	A filter with narrow bandwidth and steep skirts made using quartz crystals
B	A power supply filter made with interlaced quartz crystals
C	An audio filter made with four quartz crystals that resonate at 1kHz intervals
D	A filter with wide bandwidth and shallow skirts made using quartz crystals

33. - E7D09

What is the main reason to use a charge controller with a solar power system?

Select	Answer
A	Prevention of battery damage due to overcharge
B	Prevention of battery undercharge
C	Matching of day and night charge rates
D	Control of electrolyte levels during battery discharge

34. - E7E10

How does a diode detector function?

Select	Answer
A	By mixing signals with noise in the transition region of the diode
B	By rectification and filtering of RF signals
C	By breakdown of the Zener voltage
D	By sensing the change of reactance in the diode with respect to frequency

35. - E7F14

Which of the following would allow a digital signal processing filter to create a sharper filter response?

Select	Answer
A	More taps
B	Double-precision math routines
C	Higher data rate
D	Complex phasor representations

36. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 3300 ohms and RF is 47 kilohms?

Select	Answer
A	14
B	0.07
C	28
D	7

37. - E7H12

Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

Select	Answer
A	Bias the crystal at a specified current
B	Bias the crystal at a specified voltage
C	Provide the crystal with a specified parallel inductance
D	Provide the crystal with a specified parallel capacitance

38. - E8A07

What determines the PEP-to-average power ratio of a single-sideband phone signal?

Select	Answer
A	The degree of carrier suppression
B	The amplifier gain
C	The frequency of the modulating signal
D	The characteristics of the modulating signal

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 bandwidth compression technique using Fourier transforms
C	A digital mode for narrow band, slow speed transmissions
D	A frequency modulation technique which uses non-harmonically related frequencies

40. - E8C06

What is the necessary bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

Select	Answer
A	1.0 kHz
B	0.1 Hz
C	0.3 kHz
D	0.5 kHz

41. - E8D05

What is the most common method of reducing key clicks?

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

42. - E9A06

How does the beamwidth of an antenna vary as the gain is increased?

Select	Answer
A	It increases geometrically
B	It increases arithmetically
C	It is essentially unaffected
D	It decreases

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

Select	Answer
A	Elevation
B	Azimuth
C	Radiation resistance
D	Polarization

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

Select	Answer
A	It reduces losses in the radiating portion of the antenna
B	It changes the impedance angle of the matching network
C	It causes increased SWR
D	It reduces low-angle radiation

45. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
B	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
C	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes
D	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase

46. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

Select	Answer
A	To provide a rejection notch that prevents the radiation of harmonics
B	To transform the antenna impedance to a higher value
C	To cancel the inductive reactance of the matching network
D	To provide DC isolation between the feed line and the antenna

47. - E9F15

What impedance does a 1/2 wavelength transmission line present to a generator when the line is open 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. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

Select	Answer
A	Reactance and voltage
B	Voltage and impedance
C	Resistance and voltage
D	Resistance and reactance

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

Select	Answer
A	It automatically cancels ignition noise in mobile installations
B	It is electro statically balanced against ground, giving better nulls
C	It allows stations to communicate without giving away their position
D	It eliminates tracking errors caused by strong out-of-band signals

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	Only the most powerful transmitter
B	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations
C	Each transmitter operating with a duty-cycle greater than 50 percent
D	Only commercial transmitters

Figure E7-4

Figure E9-2