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US Amateur Radio - Amateur Extra (Element 4, 2020-2024) Practice Test

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1. - 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?

SelectAnswer
AOnly the most powerful transmitter
BOnly commercial transmitters
CEach transmitter that produces 5 percent or more of its MPE limit in areas where the total MPE limit is exceeded.
DEach transmitter operating with a duty cycle greater than 50 percent

2. - E1A02

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

SelectAnswer
AThe exact lower band edge
B300 Hz above the lower band edge
C1 kHz above the lower band edge
D3 kHz above the lower band edge

3. - E1B09

Which amateur stations may be operated under RACES rules?

SelectAnswer
AAny FCC-licensed amateur station certified by the responsible civil defense organization for the area served
BAny FCC-licensed amateur station except a Technician Class
CAny FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)
DOnly those club stations licensed to Amateur Extra Class operators

4. - E1C05

When may an automatically controlled station originate third party communications?

SelectAnswer
ANever
BOnly when transmitting RTTY or data emissions
CWhen agreed upon by the sending or receiving station
DWhen approved by the National Telecommunication and Information Administration

5. - E1D12

Which of the following amateur stations may transmit one-way communications?

SelectAnswer
AA message forwarding station or automatically controlled digital station
BA space station, beacon station, or telecommand station
CAll these choices are correct
DA local repeater or linked repeater station

6. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

SelectAnswer
ASend the application form to the FCC and inform the FCC of the grade
BReturn the application document to the examinee
CMaintain the application form with the VEC's records
DDestroy the application form

7. - 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?

SelectAnswer
A53 MHz - 54 MHz
B420 MHz - 430 MHz
C222 MHz - 223 MHz
D440 MHz - 450 MHz

8. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

SelectAnswer
AAn isotropic antenna
BA log-periodic dipole array
CA circularly polarized antenna
DA linearly polarized antenna

9. - E2B06

What is vestigial sideband modulation?

SelectAnswer
AAmplitude modulation in which one complete sideband and a portion of the other are transmitted
BNarrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier
CSpread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation
DA type of modulation in which one sideband is inverted

10. - E2C03

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

SelectAnswer
A2 meters
B30 meters
C33 centimeters
D6 meters

11. - E2D11

Which of the following data are used by the APRS network to communicate station location?

SelectAnswer
ALatitude and longitude
BTime and frequency
CPolar coordinates
DRadio direction finding spectrum analysis

12. - E2E06

What is the most common data rate used for HF packet?

SelectAnswer
A48 baud
B300 baud
C1200 baud
D110 baud

13. - E3A09

Which of the following frequency ranges is most suited for meteor scatter communications?

SelectAnswer
A1.8 MHz - 1.9 MHz
B28 MHz - 148 MHz
C220 MHz - 450 MHz
D10 MHz - 14 MHz

14. - E3B09

At what time of year is sporadic E propagation most likely to occur?

SelectAnswer
AAround the solstices, especially the winter solstice
BAround the equinoxes, especially the spring equinox
CAround the equinoxes, especially the fall equinox
DAround the solstices, especially the summer solstice

15. - E3C01

What does the radio communication term "ray tracing" describe?

SelectAnswer
AModeling a radio wave's path through the ionosphere
BThe process in which an electronic display presents a pattern
CDetermining the radiation pattern from an array of antennas
DEvaluating high voltage sources for x-rays

16. - E4A02

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

SelectAnswer
ASWR and frequency
BRF amplitude and frequency
CSWR and time
DRF amplitude and time

17. - E4B10

Which of the following methods measures intermodulation distortion in an SSB transmitter?

SelectAnswer
AModulate the transmitter using two RF signals having harmonically related frequencies and observe the RF output with a logic analyzer
BModulate the transmitter using two AF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer
CModulate the transmitter using two RF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer
DModulate the transmitter using two AF signals having harmonically related frequencies and observe the RF output with a peak reading wattmeter

18. - E4C05

What does a receiver noise floor of -174 dBm represent?

SelectAnswer
AThe noise figure of a 1 Hz bandwidth receiver
BThe galactic noise contribution to minimum detectable signal
CThe theoretical noise in a 1 Hz bandwidth at the input of a perfect receiver at room temperature
DThe minimum detectable signal as a function of receive frequency

19. - E4D01

What is meant by the blocking dynamic range of a receiver?

SelectAnswer
AThe difference in dB between the noise floor and the level of an incoming signal that will cause 1 dB of gain compression
BThe minimum difference in dB between two signals which produce third-order intermodulation products greater than the noise floor
CThe difference in dB between the noise floor and the third-order intercept point
DThe minimum difference in dB between the levels of two FM signals that will cause one signal to block the other

20. - E4E04

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

SelectAnswer
ABy installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead
BBy installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead
CBy installing a noise suppression resistor and a blocking capacitor in both leads
DBy connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads

21. - E5A08

What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?

SelectAnswer
AThe voltage leads the current by 90 degrees
BThe current leads the voltage by 90 degrees
CThe voltage and current are in phase
DThe voltage and current are 180 degrees out of phase

22. - E5B09

What is the relationship between the AC current through a capacitor and the voltage across a capacitor?

SelectAnswer
ACurrent leads voltage by 90 degrees
BVoltage and current are 180 degrees out of phase
CVoltage leads current by 90 degrees
DVoltage and current are in phase

23. - E5C01

Which of the following represents capacitive reactance in rectangular notation?

SelectAnswer
AOmega
B+jX
C-jX
DDelta

24. - E5D14

What is reactive power?

SelectAnswer
APower lost because of capacitor leakage
BPower consumed in wire resistance in an inductor
CWattless, nonproductive power
DPower consumed in circuit Q

25. - E6A10

In Figure E6-1, what is the schematic symbol for an N-channel dual-gate MOSFET?

SelectAnswer
A5
B4
C2
D6

26. - E6B10

In Figure E6-2, what is the schematic symbol for a light-emitting diode?

SelectAnswer
A7
B6
C1
D5

27. - E6C10

In Figure E6-3, what is the schematic symbol for a NOR gate?

SelectAnswer
A3
B2
C1
D4

28. - E6D11

Which type of core material decreases inductance when inserted into a coil?

SelectAnswer
ACeramic
BBrass
CFerrite
DPowdered iron

29. - E6E08

How is power supplied to the most common type of MMIC?

SelectAnswer
AMMICs require no operating bias
BThrough a resistor and/or RF choke connected to the amplifier output lead
CThrough a capacitor and RF choke connected to the amplifier input lead
DDirectly to the bias voltage (VCC IN) lead

30. - E6F07

What is a solid-state relay?

SelectAnswer
AA mechanical relay that latches in the on or off state each time it is pulsed
BA relay using transistors to drive the relay coil
CA semiconductor passive delay line
DA device that uses semiconductors to implement the functions of an electromechanical relay

31. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

SelectAnswer
AJ-K flip-flop
BMonostable multivibrator
CAstable multivibrator
DT flip-flop

32. - E7B08

How can an RF power amplifier be neutralized?

SelectAnswer
ABy feeding a 180-degree out-of-phase portion of the output back to the input
BBy increasing the driving power
CBy reducing the driving power
DBy feeding an in-phase component of the output back to the input

33. - E7C03

What advantage does a series-L Pi-L-network have over a series-L Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

SelectAnswer
AHigher efficiency
BGreater harmonic suppression
CGreater transformation range
DDoes not require a capacitor

34. - 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?

SelectAnswer
AThe high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
BThe inverter design does not require any output filtering
CIt uses a large power factor compensation capacitor to recover power from the unused portion of the AC cycle
DIt uses a diode bridge rectifier for increased output

35. - E7E08

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

SelectAnswer
ATwo and four times the original frequency
BThe two input frequencies along with their sum and difference frequencies
C1.414 and 0.707 times the input frequency
DThe square root of the product of input frequencies

36. - E7F04

What is a common method of generating an SSB signal using digital signal processing?

SelectAnswer
AA frequency synthesizer removes the unwanted sidebands
BVarying quartz crystal characteristics emulated in digital form
CSignals are combined in quadrature phase relationship
DMixing products are converted to voltages and subtracted by adder circuits

37. - E7G02

What is ringing in a filter?

SelectAnswer
AA reduction in high frequency response
BUndesired oscillations added to the desired signal
CPartial cancellation of the signal over a range of frequencies
DAn echo caused by a long time delay

38. - E7H01

What are three oscillator circuits used in amateur radio equipment?

SelectAnswer
APierce, Fenner and Beane
BColpitts, Hartley and Pierce
CTaft, Hartley and Pierce
DTaft, Pierce and negative feedback

39. - E8A11

Which of the following is a measure of the quality of an analog-to-digital converter?

SelectAnswer
AReciprocal mixing
BPower factor
CTotal harmonic distortion
DPeak envelope power

40. - E8B10

What is frequency division multiplexing?

SelectAnswer
AThe transmitted signal is divided into packets of information
BTwo or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
CTwo or more information streams are merged into a baseband, which then modulates the transmitter
DThe transmitted signal jumps from band to band at a predetermined rate

41. - E8C11

What is the relationship between symbol rate and baud?

SelectAnswer
ASymbol rate is only used for packet-based modes
BBaud is only used for RTTY
CBaud is twice the symbol rate
DThey are the same

42. - E8D02

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

SelectAnswer
ADirect sequence
BPhase compandored spread spectrum
CFrequency hopping
DBinary phase-shift keying

43. - E9A06

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

SelectAnswer
A317 watts
B126 watts
C300 watts
D2000 watts

44. - E9B10

What is the principle of a Method of Moments analysis?

SelectAnswer
AA wire is modeled as a series of segments, each having a distinct value of voltage across it
BA wire is modeled as a series of segments, each having a uniform value of current
CA wire is modeled as a single sine-wave current generator
DA wire is modeled as a single sine-wave voltage source

45. - E9C05

Which of the following is a type of OCFD antenna?

SelectAnswer
AA folded dipole center-fed with 300-ohm transmission line
BA multiband dipole antenna using one-way circular polarization for frequency diversity
CA remotely tunable dipole antenna using orthogonally controlled frequency diversity
DA dipole fed approximately 1/3 the way from one end with a 4:1 balun to provide multiband operation

46. - E9D11

Which of the following conductors would be best for minimizing losses in a station's RF ground system?

SelectAnswer
AWide flat copper strap
BStranded wire
CResistive wire, such as spark plug wire
DSolid wire

47. - E9E11

What is the primary purpose of phasing lines when used with an antenna having multiple driven elements?

SelectAnswer
AIt creates a low-angle radiation pattern
BIt ensures that each driven element operates in concert with the others to create the desired antenna pattern
CIt prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
DIt allows single-band antennas to operate on other bands

48. - E9F12

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

SelectAnswer
AThe same as the characteristic impedance of the line
BVery high impedance
CThe same as the input impedance to the generator
DVery low impedance

49. - E9G03

Which of the following is often determined using a Smith chart?

SelectAnswer
ASatellite azimuth and elevation bearings
BTrigonometric functions
CImpedance and SWR values in transmission lines
DBeam headings and radiation patterns

50. - E9H03

What is Receiving Directivity Factor (RDF)?

SelectAnswer
ARelative directivity compared to a dipole
BForward gain compared to average gain over the entire hemisphere
CRelative directivity compared to isotropic
DForward gain compared to the gain in the reverse direction

Figure E6-1

Figure E6-2

Figure E6-3